Wellness Goals · Skin condition
Psoriasis
Psoriasis (plaque psoriasis and other types) · also called Psoriasis, plaque psoriasis, scalp psoriasis, psoriasis vulgaris, soriasis
Psoriasis is a long-lasting immune-related skin condition in which skin cells multiply too quickly, causing scaly, inflamed patches. This page explains the scaly patches, the types, triggers, established treatments and linked conditions according to the NHS and NIAMS, and what systematic reviews found for curcumin, fish oil, weight loss, diet, indigo naturalis, aloe vera and other complementary options. Evidence for natural options is mostly low or mixed, they do not replace medical care, and widespread, pustular or joint symptoms need a clinician.
General information, not medical advice. Last substantive update · Not medically reviewed. A named clinician has not signed off on this page. How this page is made
About Psoriasis
Psoriasis is a long-lasting immune-related condition that causes scaly, inflamed patches because skin cells multiply too quickly. It cannot be cured but can be managed with emollients, skin treatments, light therapy and medicines chosen with a clinician. For natural options, weight loss in people with overweight is the best supported, a Mediterranean diet, topical indigo naturalis and curcumin have some low-certainty support, fish oil is mixed, and oral vitamin D did not help. Widespread, pustular or joint symptoms need a doctor.
What psoriasis is: scaly patches and types
NIAMS describes psoriasis as a chronic immune-related disease in which skin cells multiply too quickly, causing scaly, inflamed patches, most often on the scalp, elbows and knees. The NHS describes dry, itchy patches with silvery-white scales, about 1 to 2 cm, pink or red on white skin and grey on brown or black skin, sometimes leaving dark marks. Nails can be pitted, and symptoms come and go in flare-ups. It is not contagious.
NIAMS lists five types: plaque (the most common), guttate (small red dots), pustular (pus-filled bumps, usually on hands and feet), inverse (smooth red patches in skin folds) and erythrodermic (rare but serious, with red scaly skin over most of the body). It can start at any age; the NHS says it often starts at 15 to 25 or 50 to 60.
Causes and triggers
NIAMS says an overactive immune system, genetics and environmental factors are involved, and family history raises the chance. The NHS lists triggers including stress, alcohol, smoking, obesity, pregnancy, certain medicines, infections (such as strep A and HIV), skin injuries and sunlight. NIAMS adds sunburn.
A 2026 meta-analysis of 30 observational studies found smoking linked with a higher chance of developing psoriasis (relative estimate 1.67) and alcohol with a smaller link (1.33, weaker after adjustment).
How psoriasis is evaluated
The NHS and NIAMS pages read do not set out the diagnostic steps. The NHS says treatment depends on the type, severity and location, and that a GP can prescribe some treatments or refer you to a dermatologist. In guidelines and trials, severity is usually measured with the PASI score (0 to 72) and quality of life with the DLQI questionnaire. The joint AAD and National Psoriasis Foundation guideline covers severity assessment.
Established treatments, in general terms
The NHS lists emollients (moisturisers), vitamin D preparations, steroid creams and coal tar, with light therapy and other medicines for more severe disease. NIAMS says mild psoriasis can often be treated with creams or ointments, while moderate and severe disease may need pills, injections or light treatment. The NHS also advises a balanced diet, regular exercise, reducing stress, limiting alcohol and stopping smoking. These choices belong with a clinician.
Linked health conditions
NIAMS links psoriasis with psoriatic arthritis, heart attacks and strokes, anxiety and depression, diabetes, metabolic syndrome, obesity, Crohn's disease and other conditions. The NHS mentions psoriatic arthritis, metabolic syndrome and inflammatory bowel disease. Tell a clinician about joint pain, stiffness or swelling that keeps returning, because untreated psoriatic arthritis can cause irreversible joint damage.
What curcumin, fish oil, diet and other complementary options show
The best-supported lifestyle step is weight loss in people with overweight or obesity: a 2026 meta-analysis of 13 trials (1,145 people) found a PASI fall of 2.5 points, and the National Psoriasis Foundation strongly recommends it alongside standard care. A small 2025 trial found a Mediterranean diet lowered PASI by 3.4 points. Topical indigo naturalis beat placebo in 5 trials (215 people) and curcumin improved psoriasis in 3 small trials (118 people), both low certainty. Fish oil results are mixed, oral vitamin D did not help in a 122-person trial, and a 40-study review found insufficient evidence to recommend complementary treatments. See the Health Benefits and Evidence tabs.
At a glance
Traditional uses history, not proof
Studied for research
- Weight loss (overweight or obesity), moderate certainty
- Mediterranean diet, low certainty
- Mindfulness and stress management, low certainty
- Stopping smoking, limiting alcohol, insufficient evidence
- Salt-water baths with UVB, low certainty
- Curcumin, low certainty
- Indigo naturalis on the skin, low certainty
- Fish oil and omega-3, mixed evidence
Main compounds
- Curcumin
- Indigo naturalis
- Omega-3 fatty acids
- Vitamin D
- Aloe vera extract
- Mahonia aquifolium extract
Common forms
- Skin-applied creams and ointments
- Oral supplements
- Eating patterns and weight loss
- Salt baths with light treatment
Research links: NHS: Psoriasis · NIAMS: Psoriasis · Complementary therapies for psoriasis, JAMA Dermatology 2018 · Weight-loss interventions and psoriasis severity, 2026 · NPF dietary recommendations for psoriasis, 2018 · Lifestyle changes for treating psoriasis, Cochrane 2019 · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Psoriasis
- Common names
- Psoriasis (English); Plaque psoriasis, scalp psoriasis (English); Psoriasis (Spanish); Soriasis, placas escamosas (Spanish)
What is inside, and how it may work
What it contains and how those compounds act in cells and animals. Laboratory and animal mechanisms are not proven effects in people.
Main compounds
| Compound | Family | Where it is concentrated | Activity studied | Level of evidence |
|---|---|---|---|---|
| Curcumin | polyphenol | Studied by mouth and on the skin. 22 | Human data | |
| Indirubin and tryptanthrin (indigo naturalis) | plant compounds | Studied on the skin; tryptanthrin blocked IL-17 signals in a skin-cell assay. 3 13 | Human and laboratory | |
| Omega-3 fatty acids | fatty acid | Studied as fish oil supplements. 21 4 | Human data | |
| Vitamin D (cholecalciferol) | vitamin | Studied by mouth. 9 | Human data | |
| Aloe vera extract | plant extract | Studied on the skin. 17 | Human data | |
| Mahonia aquifolium extract | plant extract | Studied on the skin. 1 | Human data |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| How psoriasis forms | NIAMS: an overactive immune system with genetic and environmental factors; skin cells multiply too quickly. The NHS says it is more likely with a family member who has it. 26 24 | Agency summary | |
| IL-17 pathway | In a small trial, skin gene signs of the IL-17 pathway, which was raised in psoriasis, moved toward normal with indigo naturalis. The study cannot show this is how it improves symptoms. 3 | Human tissue study |
Isolated compounds versus whole extracts
Trials tested isolated curcumin, plant extracts and fish oil, not whole turmeric root, whole aloe leaf or foods. Diet patterns such as the Mediterranean diet were tested as whole programmes.
1 moderate certainty2 mixed findings7 low certainty2 not enough evidence
What was looked at
The 12 benefits and uses checked for Psoriasis, each with how strong the evidence is. Tap one to open it.
- Weight loss in people with overweight or obesityModerate certainty
- Mediterranean diet and other eating patternsLow certainty
- Mindfulness, meditation and stress managementLow certainty
- Stopping smoking and limiting alcoholNot enough evidence
- Salt-water baths and climatotherapy (spa treatments)Low certainty
- Curcumin (from turmeric)Low certainty
- Indigo naturalis (topical, from Traditional Chinese Medicine)Low certainty
- Fish oil and omega-3 fatty acidsMixed findings
- Vitamin D by mouthMixed findings
- Aloe vera on the skinLow certainty
- Mahonia aquifolium (Oregon grape) creamLow certainty
- Complementary treatments as a groupNot enough evidence
Lab markers tracked in the studies
Psoriasis Area and Severity Index (PASI)PASI 75 responseDermatology Life Quality Index (DLQI)
What is Psoriasis good for?
The natural and lifestyle approaches that have been studied for psoriasis, and how strong the human evidence is for each. These describe what studies found, not advice to use them. They do not replace the care described in the About tab.
Benefits, one by one
Each card is a research question, not a promise. Tap a goal to filter. Open a card to see the studies, doses and limits.
Weight loss in people with overweight or obesity
Moderate certaintyAcross 13 randomised trials (1,145 people), weight-loss programmes lowered psoriasis severity scores and more people reached a 75 percent improvement. The National Psoriasis Foundation strongly recommends weight reduction for overweight and obese people with psoriasis, alongside standard care.
4 studiesLow-calorie diets, diet with exercise, and in a few trials weight-los…
Studies, doses and limits
What the trials found
2026 meta-analysis of 13 RCTs (1,145 people); 2015 meta-analysis of 7 RCTs (878 people); Cochrane review of 10 lifestyle RCTs (1,163 people); NPF diet review of 55 studies.
Results
Average weight fell by 6.7 kg. PASI fell more than in controls (MD -2.5, CI -3.8 to -1.1), PASI 75 was more likely (RR 1.6, CI 1.1 to 2.2) and quality-of-life scores improved (DLQI MD -5.0). The Cochrane review rated the low-calorie diet result low quality (PASI 75 RR 1.66) and the diet-plus-exercise result moderate, with an interval that includes little or no difference.
Effect sizes as reported
PASI -2.5; PASI 75 RR 1.6
Why this rating
Moderate, the compiler's rating: consistent direction across several reviews and a strong guideline recommendation, but trials differ a lot (I2 85 percent), some used weight-loss medicines, and many had high risk of bias. The 2026 review's authors call it high certainty; the Cochrane review calls the diet evidence low to moderate.
Form and dose studied
Low-calorie diets, diet with exercise, and in a few trials weight-loss medicines, as reported. No amounts are advised here.
Who was studied
Adults with psoriasis, mostly with overweight or obesity.
Limits
Results apply to people with overweight or obesity. Unclear how long benefits last.
Why researchers looked
Excess weight raises the chance of psoriasis and is linked with more severe disease; about 80 percent of people with psoriasis also have overweight or obesity (2026 review).
Proposed mechanism Hypothesis
Proposed: fat tissue produces inflammatory signals. Not tested in the reviews read.
A proposed mechanism does not show that the effect happens in people.
Rapid or very restrictive diets need medical supervision, especially with diabetes, pregnancy, an eating disorder history or in teenagers.
Mediterranean diet and other eating patterns
Low certaintyOne small 2025 randomised trial (38 adults with mild to moderate psoriasis) found that 16 weeks of a dietitian-guided Mediterranean diet lowered PASI by 3.4 points more than standard low-fat advice. It is one small trial, so the result needs confirming.
2 studiesA dietitian-led programme with counselling and weekly extra virgin ol…
Studies, doses and limits
What the trials found
MEDIPSO randomised trial (38 people, Madrid); the NPF review of 55 studies for other diets.
Results
PASI change -3.4 (CI -4.4 to -2.4) in the diet group versus 0.0 in controls; 9 of 19 (47.4 percent) reached PASI 75 versus none. The NPF review found select foods and patterns may affect psoriasis based on low-quality data, and weakly recommends a gluten-free diet only in people with positive gluten-sensitivity blood tests.
Effect sizes as reported
Between-group PASI difference -3.4
Why this rating
Low, the compiler's rating: promising size of effect, but one small, single-centre, open-label trial with an unequal attention level between groups.
Form and dose studied
A dietitian-led programme with counselling and weekly extra virgin olive oil for 16 weeks. No amounts are advised here.
Who was studied
Adults with mild to moderate psoriasis on stable topical treatment.
Limits
One centre, 38 people, open-label; control group had no dietitian support.
Why researchers looked
The Mediterranean diet has anti-inflammatory and heart-health features that might matter in psoriasis.
Proposed mechanism Hypothesis
Proposed in the trial: anti-inflammatory and metabolic effects. Blood sugar markers also improved.
A proposed mechanism does not show that the effect happens in people.
Ask a clinician or dietitian first if you have food allergies or take diabetes medicines. Do not drop prescribed treatment.
Mindfulness, meditation and stress management
Low certaintyA small 1998 trial (37 people) found that a mindfulness audiotape played during light therapy helped skin clear faster. Reviews describe meditation and stress-management approaches as promising but based on few, small studies.
3 studiesMindfulness-based stress reduction delivered by audiotape during ligh…
Studies, doses and limits
What the trials found
One randomised trial (37 people having UVB or PUVA); a 2018 systematic review (3 single-blind RCTs, 112 people, meditation and guided imagery); a 2021 narrative review.
Results
The tape group reached the halfway point (p = 0.013) and clearing point (p = 0.033) sooner. The 2018 review reported modest efficacy for meditation and guided imagery.
Effect sizes as reported
Faster clearing in a small trial
Why this rating
Low, the compiler's rating: small trials, not fully blinded, and only a clear benefit for people already having light therapy.
Form and dose studied
Mindfulness-based stress reduction delivered by audiotape during light treatments, as reported.
Who was studied
People with moderate to severe psoriasis having light treatments; other trials in adults with plaque psoriasis.
Limits
Small, older trials; effect outside light treatment is less clear.
Why researchers looked
Stress is a recognised trigger of flare-ups, and psoriasis itself can affect mood.
Proposed mechanism Hypothesis
Proposed: stress affects the immune system. Not tested directly here.
A proposed mechanism does not show that the effect happens in people.
No safety concerns were reported in the abstracts. If psoriasis is affecting your mood, talk to a clinician; the NHS says mental health support is available.
Stopping smoking and limiting alcohol
Not enough evidenceSmoking and alcohol are linked with a higher chance of developing psoriasis, and the NHS lists both as triggers and advises limiting alcohol and stopping smoking. No trial yet shows that stopping them clears existing psoriasis.
3 studiesThis is about daily habits, not a product.
Studies, doses and limits
What the trials found
A 2026 meta-analysis of 30 observational studies (over 25 million people); the Cochrane lifestyle review, which found no trials of alcohol abstinence or smoking cessation; NHS page.
Results
Smoking raised the chance of psoriasis (relative estimate 1.67, CI 1.46 to 1.90) with a dose-response pattern; former smokers 1.38. Alcohol was 1.33 (CI 1.16 to 1.53), falling to 1.19 after adjustment, so the authors call it less robust.
Effect sizes as reported
Smoking 1.67; alcohol 1.33
Why this rating
Insufficient for treatment benefit, the compiler's rating: the evidence concerns risk of developing psoriasis in observational studies, and the Cochrane review found no trials of stopping.
Form and dose studied
This is about daily habits, not a product.
Who was studied
General adult populations in observational studies.
Limits
Observational links cannot show cause; no trial of stopping in people who already have psoriasis.
Why researchers looked
Both are common, changeable habits that observational studies link with psoriasis.
Proposed mechanism Hypothesis
Not tested in the reviews read.
A proposed mechanism does not show that the effect happens in people.
Stopping smoking and limiting alcohol are widely advised for general health; a pharmacist or GP can help.
Salt-water baths and climatotherapy (spa treatments)
Low certaintyA Cochrane review of 8 trials found that indoor salt-water baths followed by UVB light may improve psoriasis more than UVB alone, but the certainty is low. Reviews also describe positive results for climatotherapy at places such as the Dead Sea.
2 studiesSalt baths given before artificial UVB in clinics or spas. Home bath …
Studies, doses and limits
What the trials found
Cochrane review of 8 RCTs (6 with 2,035 people); a 2021 narrative review of mind-body and spa therapies (34 articles on climatotherapy or balneotherapy).
Results
PASI 75 was more likely with salt bath plus UVB than UVB alone (RR 1.71, CI 1.24 to 2.35; 278 people; low certainty). Side effects causing withdrawal were similar (RR 0.96). The narrative review called climatotherapy and balneotherapy effective for clinical improvement.
Effect sizes as reported
PASI 75 RR 1.71
Why this rating
Low, the Cochrane review's own rating: few trials, assessors not blinded, and some trials were funded by spa or salt interests. All trials were in Europe.
Form and dose studied
Salt baths given before artificial UVB in clinics or spas. Home bath salts were not the studied treatment.
Who was studied
Adults with chronic plaque psoriasis.
Limits
Results are about baths combined with supervised UVB, not baths alone.
Why researchers looked
Spa and sea-water treatments have long been used for skin diseases, and sunlight helps psoriasis.
Proposed mechanism Hypothesis
Proposed: salt softens scale and helps light reach the skin. Not tested directly here.
A proposed mechanism does not show that the effect happens in people.
One person had severe itch after a Dead Sea salt soak in a trial. The NHS lists sunburn and sunlight among triggers, so light treatment belongs under medical supervision.
Curcumin (from turmeric)
Low certaintyA 2018 review found that curcumin improved psoriasis in 3 randomised trials (118 people), and a 2022 meta-analysis of clinical trials found lower PASI scores than controls. The trials are few and small and used different forms.
2 studiesOral curcumin, topical curcumin and combinations were studied. No amo…
Studies, doses and limits
What the trials found
2018 systematic review (3 RCTs, 118 people); 2022 meta-analysis of 7 clinical RCTs and 19 preclinical studies.
Results
Both oral and topical or combination uses improved PASI compared with controls (standardised mean difference -0.83, p = 0.02). The reported interval in the abstract appears inconsistent, so the number should be treated with caution.
Effect sizes as reported
Standardised MD -0.83
Why this rating
Low, the compiler's rating: small trials, mixed forms (alone or added to standard treatment), and the authors say efficacy and safety are not confirmed.
Form and dose studied
Oral curcumin, topical curcumin and combinations were studied. No amounts are advised here.
Who was studied
Adults with plaque psoriasis in a few small RCTs.
Limits
Few trials and different forms.
Why researchers looked
Curcumin is an anti-inflammatory compound from turmeric.
Proposed mechanism Hypothesis
Proposed: lowers inflammatory signals such as IL-17 and TNF in animal and cell studies. Not shown in people in the reviews read.
A proposed mechanism does not show that the effect happens in people.
Safety of curcumin products was not covered in detail by the reviews read. Ask a pharmacist before using one, especially if you take regular medicines. See the turmeric page.
Indigo naturalis (topical, from Traditional Chinese Medicine)
Low certaintyIndigo naturalis ointment applied to the skin did better than placebo in 5 randomised trials (215 people) in a 2018 review. In one trial 56 percent of 16 treated people reached 75 percent improvement versus none on placebo. A dose-comparison trial found a stronger ointment worked best.
4 studiesTopical ointments twice daily for 8 weeks in trials; strengths varied…
Studies, doses and limits
What the trials found
2018 JAMA Dermatology review (5 RCTs, 215 people); placebo-controlled RCT (24 people, NCT01901705); dose-controlled RCT of a refined ointment.
Results
PASI 75 in 56.3 percent with indigo naturalis versus 0 percent with placebo at week 8. In the dose trial, PASI fell 69.2 percent with the strongest ointment and no severe treatment-related adverse events occurred over 20 weeks. A 2013 review pooled it with other plant extracts and found limited support.
Effect sizes as reported
PASI 75: 56.3 percent versus 0 percent
Why this rating
Low, the compiler's rating: consistent positive trials but all small, products and strengths varied.
Form and dose studied
Topical ointments twice daily for 8 weeks in trials; strengths varied. No amounts are advised here.
Who was studied
Adults with chronic plaque psoriasis.
Limits
Small trials and short duration.
Why researchers looked
A blue plant-based powder long used in Traditional Chinese Medicine for psoriasis.
Proposed mechanism Hypothesis
Proposed: the compound tryptanthrin blocks IL-17 signals in skin cells in the lab; treated skin showed IL-17 pathway genes moving toward normal.
A proposed mechanism does not show that the effect happens in people.
The trials reported no severe treatment-related adverse events with the refined ointment; the abstracts do not list milder effects. Ask a clinician before using it on large areas.
Fish oil and omega-3 fatty acids
Mixed findingsTwo 2019 meta-analyses disagree. One of 13 trials found no clear effect of fish oil on psoriasis severity, and another of 10 studies found a small PASI improvement with omega-3. Most placebo-controlled trials in the 2018 JAMA Dermatology review showed no significant improvement.
3 studiesFish oil capsules or infusions in various amounts as reported. No amo…
Studies, doses and limits
What the trials found
Meta-analysis of 13 RCTs (625 people; 3 pooled); meta-analysis of 10 studies (560 people); 2018 review of 12 RCTs.
Results
Fish oil: PASI difference -0.28 (CI -1.74 to 1.19), no significant effect. Omega-3: PASI -1.58 (CI -2.24 to -0.92) plus less erythema and scaling, mostly with higher amounts.
Effect sizes as reported
PASI -0.28 versus -1.58 in two reviews
Why this rating
Mixed, the compiler's rating: two similar reviews reached opposite conclusions and most randomised trials were negative.
Form and dose studied
Fish oil capsules or infusions in various amounts as reported. No amounts are advised here.
Who was studied
Adults with psoriasis in small RCTs.
Limits
Different products, amounts and designs.
Why researchers looked
Omega-3 fats are involved in inflammation.
Proposed mechanism Hypothesis
Proposed: calming inflammation. Not tested directly here.
A proposed mechanism does not show that the effect happens in people.
Safety details were not given in the abstracts read. Ask a pharmacist before taking fish oil, especially if you take blood thinners.
Vitamin D by mouth
Mixed findingsA 2023 randomised trial of 122 adults with low blood vitamin D found no difference in psoriasis severity after 4 months. A 2021 meta-analysis could not verify a benefit. Vitamin D creams are a different, prescribed treatment.
3 studiesOral cholecalciferol as a loading dose then weekly in the trial. No a…
Studies, doses and limits
What the trials found
JAMA Dermatology RCT (122 people, Norway); meta-analysis of 3 pooled RCTs.
Results
No difference in PASI (adjusted difference 0.11, CI -0.23 to 0.45). The meta-analysis showed PASI -0.92 at 6 months, but not after adjustment for few studies (CI -2.21 to 0.38). NPF weakly recommends vitamin D supplementation for psoriatic arthritis.
Effect sizes as reported
No clear effect
Why this rating
Mixed, leaning to no benefit: the largest trial was negative, though disease was mild at the start and the meta-analysis was fragile.
Form and dose studied
Oral cholecalciferol as a loading dose then weekly in the trial. No amounts are advised here.
Who was studied
Adults with plaque psoriasis and low-range vitamin D.
Limits
Mild psoriasis at baseline; blood levels rose less than expected.
Why researchers looked
Vitamin D is involved in skin and immune function, and blood levels are often low in psoriasis.
Proposed mechanism Hypothesis
Not tested in the reviews read.
A proposed mechanism does not show that the effect happens in people.
No adverse effects were registered in the trial. Ask a clinician about blood tests and amounts before supplementing; see the vitamin D page.
Aloe vera on the skin
Low certaintyAn older trial reported that 0.5 percent aloe cream cleared psoriasis in most people versus few on placebo, and a 2013 review says there is limited support for topical aloe. NCCIH says only a small amount of research suggests it may help.
3 studies0.5 percent aloe extract in a cream, 3 times daily in the trial. No a…
Studies, doses and limits
What the trials found
1996 placebo-controlled trial (60 people); 2013 meta-analysis (3 aloe studies); NCCIH page.
Results
25 of 30 (83.3 percent) cured with aloe versus 2 of 30 with placebo in one trial. The 2013 review could not measure the size of any effect because of small studies and weak methods.
Effect sizes as reported
Cure 83.3 percent versus 6.6 percent in one older trial
Why this rating
Low, the compiler's rating: positive but old and small trials with unusual outcome definitions; NCCIH calls the evidence limited.
Form and dose studied
0.5 percent aloe extract in a cream, 3 times daily in the trial. No amounts are advised here.
Who was studied
Adults with slight to moderate chronic plaque psoriasis.
Limits
Small trials.
Why researchers looked
Aloe gel is a traditional skin soother.
Proposed mechanism Hypothesis
Not tested in the reviews read.
A proposed mechanism does not show that the effect happens in people.
NCCIH says topical aloe gel is generally well tolerated but burning, itching or rash can occur. Aloe by mouth may be unsafe in pregnancy and aloe leaf extract has been linked to hepatitis.
Mahonia aquifolium (Oregon grape) cream
Low certaintyA 200-person trial found a Mahonia aquifolium cream improved psoriasis scores more than placebo, and the 2013 review lists Mahonia as one of three plant extracts with limited support. The tested product was a homeopathic preparation.
2 studiesA proprietary extract cream twice daily for 12 weeks. No amounts are …
Studies, doses and limits
What the trials found
Randomised placebo-controlled trial (200 people, 12 weeks); 2013 meta-analysis of 5 Mahonia studies.
Results
PASI and quality of life improved more than with placebo (p under 0.05). Side effects were under 1 percent: rash, burning and clothing stains.
Effect sizes as reported
Statistically significant, size not given
Why this rating
Low, the compiler's rating: positive trials but product-specific, with no numbers in the abstract and the same product used throughout.
Form and dose studied
A proprietary extract cream twice daily for 12 weeks. No amounts are advised here.
Who was studied
Adults with mild to moderate psoriasis.
Limits
Product-specific; few independent trials.
Why researchers looked
A North American shrub whose bark extract has been used on the skin.
Proposed mechanism Hypothesis
Not tested in the reviews read.
A proposed mechanism does not show that the effect happens in people.
Burning or rash on application is possible. Not enough information was read on pregnancy or children, so ask a clinician.
Complementary treatments as a group
Not enough evidenceA 2021 meta-analysis of 40 studies across acne, eczema and psoriasis concluded the evidence is insufficient to recommend complementary treatments, and the psoriasis scores could not be told apart from no change. A 2018 review picked out a few with stronger support.
3 studiesVarious.
Studies, doses and limits
What the trials found
Meta-analysis of 40 studies; 2018 JAMA Dermatology review of 44 RCTs; AAD-NPF guideline on topical and alternative treatments.
Results
Pooled PASI results for psoriasis had ranges including no effect (SMD 3.04, CI -0.35 to 6.43; SMD 5.16, CI -0.52 to 10.85). The 2018 review found the best evidence for indigo naturalis, curcumin, meditation and guided imagery.
Effect sizes as reported
No pooled benefit shown
Why this rating
Insufficient, the authors' own conclusion in the 2021 meta-analysis: studies differ in design, size and measures.
Form and dose studied
Various.
Who was studied
Adults with psoriasis.
Limits
Small trials with different measures.
Why researchers looked
Many people with psoriasis use complementary therapies; the 2018 review says up to 51 percent do.
Proposed mechanism Hypothesis
A group of different treatments, so there is no single mechanism.
A proposed mechanism does not show that the effect happens in people.
Do not stop prescribed treatment for a complementary one. Tell your clinician what you use.
Connections to the rest of health
How Psoriasis connects to the rest of our health knowledge graph. Every link says what kind of connection it is. A safety link (for example to the liver) is a warning, not a benefit. A study that merely mentions a topic never creates a benefit link.
Explore every connection: goals, body systems, organs, symptoms, genes
A. Wellness goals
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Skin Health | Moderate certainty | Weight loss in people with overweight or obesity: Across 13 randomised trials (1,145 people), weight-loss programmes lowered psoriasis severity scores and more people reached a 75 percent improvement. The National Psoriasis Foundation strongly recommends weight reduction for overweight and obese people with psoriasis, alongside standard care. Salt-water baths and climatotherapy (spa treatments): A Cochrane review of 8 trials found that indoor salt-water baths followed by UVB light may improve psoriasis more than UVB alone, but the certainty is low. Reviews also describe positive results for climatotherapy at places such as the Dead Sea. | 14 20 12 7 15 19 8 22 21 4 10 6 | |
| Skin Health | Low certainty | Mediterranean diet and other eating patterns: One small 2025 randomised trial (38 adults with mild to moderate psoriasis) found that 16 weeks of a dietitian-guided Mediterranean diet lowered PASI by 3.4 points more than standard low-fat advice. It is one small trial, so the result needs confirming. Mindfulness, meditation and stress management: A small 1998 trial (37 people) found that a mindfulness audiotape played during light therapy helped skin clear faster. Reviews describe meditation and stress-management approaches as promising but based on few, small studies. | 16 7 11 8 19 3 13 5 9 18 17 23 1 | |
| Skin Health | Not enough evidence | Stopping smoking and limiting alcohol: Smoking and alcohol are linked with a higher chance of developing psoriasis, and the NHS lists both as triggers and advises limiting alcohol and stopping smoking. No trial yet shows that stopping them clears existing psoriasis. | 2 12 24 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Integumentary System | Biological association | Moderate certainty | Studied for: Weight loss in people with overweight or obesity Studied for: Mediterranean diet and other eating patterns | 14 20 12 7 16 11 8 19 2 24 15 22 3 13 5 21 4 9 18 17 23 1 10 6 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Psoriasis Area and Severity Index (PASI) | Biological association | Moderate certainty | Measured in trials: fell with weight loss, Mediterranean diet and topical indigo naturalis in trials. A lab change is not the same as a health benefit. | 14 16 9 |
| PASI 75 response | Biological association | Moderate certainty | Measured in trials: more likely with weight loss, indigo naturalis and salt bath plus UVB. A lab change is not the same as a health benefit. | 14 15 3 |
| Dermatology Life Quality Index (DLQI) | Biological association | Low certainty | Measured in trials: improved with weight loss. A lab change is not the same as a health benefit. | 14 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Curcumin | Biological association | Human | Studied by mouth and on the skin. | 22 |
| Indirubin and tryptanthrin (indigo naturalis) | Biological association | Human and laboratory | Studied on the skin; tryptanthrin blocked IL-17 signals in a skin-cell assay. | 3 13 |
| Omega-3 fatty acids | Biological association | Human | Studied as fish oil supplements. | 21 4 |
| Vitamin D (cholecalciferol) | Biological association | Human | Studied by mouth. | 9 |
| Aloe vera extract | Biological association | Human | Studied on the skin. | 17 |
| Mahonia aquifolium extract | Biological association | Human | Studied on the skin. | 1 |
Each connection is stored with the ingredient, the connected record, the kind of connection, the evidence status, the supporting studies, the preparation or compound involved, and a review date (last reviewed October 31, 2026).
Evidence at a glance: what the research found for 12 outcomes
Each outcome below is one thing researchers measured. Certainty is how far the evidence can be trusted, not how well it works. The full studies are on the next tab.
The evidence
The research centre for Psoriasis. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.
Evidence by outcome
Bars show how many studies we found for each outcome, not how well it works. People are added up across trials only (reviews are not added, to avoid double counting).
How we rate evidence
High certainty
Several well-run trials or reviews agree; further research is unlikely to change the picture much.
Moderate certainty
Good trials point the same way, but some doubt remains.
Low certainty
Small, short or inconsistent trials. The finding could change with better research.
Very low certainty
Very little or very weak human data. Treat as a possibility only.
Mixed findings
Trials or reviews disagree with each other.
Not enough evidence
Not enough human research to say either way.
Evidence against
Good research found no benefit, or found harm.
We take the reviewers' own risk-of-bias and GRADE statements where they exist, and otherwise judge from study size, design, consistency, directness and whether a product matches what is sold. Many publications do not make evidence high. Method note: We searched PubMed, read the abstract of every review, trial and guideline cited, and read the NHS, NIAMS and NCCIH pages through a tool that summarises pages. Certainty ratings are the compiler's own reading unless a review gives its own grade.
Study library: every study we checked 26
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Bernstein 2006 Treatment of mild to moderate psoriasis with Reliéva, a Mahonia aquifolium extract--a double-blind, placebo-controlled study Am J Ther · PMID 16645428 · DOI |
Randomised controlled trial |
200 200 people with mild to moderate psoriasis |
Relieva cream (a homeopathic product with a Mahonia aquifolium extract) twice daily for 12 weeks · vs Placebo cream |
PASI and quality of life improved more with the Mahonia cream than placebo (p under 0.05). Side effects were under 1 percent and minor: rash, burning on application and clothing stains. Statistically significant, size not given in the abstract Methods, limits and fundingOutcomes: PASI and quality of life Limitations: Product-specific trial of one proprietary extract; the abstract gives no numbers. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Chen 2026 Smoking, alcohol consumption, and psoriasis risk: a systematic review and dose-response meta-analysis of observational studies Front Public Health · PMID 42326923 · DOI |
Meta analysis observational |
30 observational studies, over 25 million participants | Smoking and alcohol as risk factors · vs Never smokers and non-drinkers |
Smoking: relative estimate 1.67 (CI 1.46 to 1.90) with a dose-response pattern; former smokers 1.38 (CI 1.18 to 1.62). Alcohol: 1.33 (CI 1.16 to 1.53), reduced to 1.19 (CI 1.02 to 1.37) after adjusting for missing studies, so the authors call it less robust. Smoking 1.67; alcohol 1.33 (1.19 adjusted) Methods, limits and fundingOutcomes: Risk of developing psoriasis Limitations: Observational links about developing psoriasis, not about whether stopping clears existing psoriasis. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Cheng 2017 Clinical efficacy and IL-17 targeting mechanism of Indigo naturalis as a topical agent in moderate psoriasis BMC Complement Altern Med · PMID 28865459 · DOI |
Randomised controlled trial |
24 24 adults with moderate plaque psoriasis, China |
Indigo naturalis ointment twice daily for 8 weeks · vs Matched placebo |
56.3 percent of treated people reached PASI 75 versus 0 percent with placebo at week 8. The IL-17 pathway genes seen in psoriasis skin moved back toward normal. PASI 75: 56.3 percent versus 0 percent Methods, limits and fundingOutcomes: PASI and skin gene expression Limitations: Only 24 people (16 treated, 8 placebo). Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Clark 2019 Efficacy of ω-3 supplementation in patients with psoriasis: a meta-analysis of randomized controlled trials Clin Rheumatol · PMID 30778861 · DOI |
Systematic review meta analysis |
560 10 studies (560 people) of omega-3 in psoriasis |
Omega-3 polyunsaturated fatty acid supplements · vs Control groups |
PASI fell by 1.58 (CI -2.24 to -0.92) in favour of omega-3; erythema and scaling also fell. Improvements in erythema, itching and scale were seen in trials that used higher amounts. The authors call for well-controlled randomised studies to confirm equivocal findings. PASI -1.58 Methods, limits and fundingOutcomes: PASI, erythema, scaling, itching Limitations: Included studies of varying design; the result differs from the other meta-analysis of fish oil in the same year. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Deng 2013 Plant extracts for the topical management of psoriasis: a systematic review and meta-analysis Br J Dermatol · PMID 23909714 · DOI |
Systematic review meta analysis |
12 RCTs of single-plant extracts used on the skin in psoriasis | Mahonia aquifolium (5 studies), Aloe vera (3), indigo naturalis (2), kukui nut oil (1), Camptotheca acuminata (1) · vs Placebo or controls |
Six studies could be pooled; five against placebo gave a relative risk of 3.37 (CI 1.36 to 8.33). The authors say the trials give limited support for Mahonia, indigo naturalis and aloe on plaque psoriasis. No serious adverse events were reported. Because most studies were small and weak in method, strong conclusions cannot be made. RR 3.37 for clinical efficacy versus placebo Methods, limits and fundingOutcomes: Clinical efficacy, PASI, quality of life Limitations: Small studies and variable quality; the size of any effect cannot be measured accurately. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Elmets 2021 Joint AAD-NPF Guidelines of care for the management and treatment of psoriasis with topical therapy and alternative medicine modalities for psoriasis severity measures J Am Acad Dermatol · PMID 32738429 · DOI |
Clinical guideline |
Adults with psoriasis | Topical therapy and alternative medicine modalities; severity measures · vs Varies by recommendation |
The abstract states that the guideline covers topical agents, alternative medicine and severity assessment in adults and says psoriasis affects up to 3.2 percent of the United States population. The abstract does not list the individual recommendations, and the full text was not read. Not given in the abstract Methods, limits and fundingOutcomes: Recommendations for topical treatment, alternative medicine and severity assessment Limitations: Only the abstract was read, so the specific recommendations on alternative medicine are not reported here. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Ford 2018 Dietary Recommendations for Adults With Psoriasis or Psoriatic Arthritis From the Medical Board of the National Psoriasis Foundation: A Systematic Review JAMA Dermatol · PMID 29926091 · DOI |
Systematic review |
55 studies, 77,557 people of whom 4,534 had psoriasis (adults with psoriasis or psoriatic arthritis) | Diet changes, nutrients and dietary patterns · vs Usual diet or controls |
The board strongly recommends weight reduction with a lower-calorie diet in overweight and obese people with psoriasis. It weakly recommends a gluten-free diet only in people who test positive for serologic markers of gluten sensitivity. Other foods, nutrients and patterns showed possible effects based on low-quality data. Dietary changes should always be used together with standard medical therapy. Strong recommendation for weight reduction; weak for gluten-free diet in test-positive people Methods, limits and fundingOutcomes: Diet recommendations from the National Psoriasis Foundation Medical Board Limitations: Many included studies were observational; evidence for specific foods is low quality. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Gamret 2018 Complementary and Alternative Medicine Therapies for Psoriasis: A Systematic Review JAMA Dermatol · PMID 30193251 · DOI |
Systematic review |
Adults with plaque psoriasis; 44 RCTs plus uncontrolled studies and 3 meta-analyses (searches 1950 to 2017) | Complementary therapies: indigo naturalis, curcumin, fish oil, meditation and guided imagery, acupuncture · vs Placebo or comparison groups in the trials |
Topical indigo naturalis improved psoriasis versus placebo in 5 RCTs (215 people). Curcumin was studied in 3 RCTs (118 people) plus 2 non-randomised studies and showed improvement. Most of 12 fish oil RCTs showed no significant improvement. Meditation and guided imagery (3 single-blind RCTs, 112 people) showed modest efficacy. One meta-analysis of 13 RCTs reported benefit of acupuncture. See results Methods, limits and fundingOutcomes: Skin clearing in plaque psoriasis Limitations: Only therapies with more than one RCT were kept; many trials were small, single-blind or not blinded; product quality varied. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Jenssen 2023 Effect of Vitamin D Supplementation on Psoriasis Severity in Patients With Lower-Range Serum 25-Hydroxyvitamin D Levels: A Randomized Clinical Trial JAMA Dermatol · PMID 36988936 · DOI |
Randomised controlled trial |
122 122 adults with active plaque psoriasis and low-range blood vitamin D (under 24 ng/mL), Tromsø, Norway, over two winters |
Oral vitamin D (loading dose then weekly) for 4 months · vs Placebo |
No difference in PASI change (adjusted difference 0.11, CI -0.23 to 0.45), nor in physician global assessment or quality of life. No adverse effects were registered. Baseline severity was low (mean PASI 3.1), which may hide an effect. PASI difference 0.11 (no effect) Methods, limits and fundingOutcomes: PASI at 4 months Limitations: Mild disease at the start; blood vitamin D rose less than expected. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Jones 2021 Complementary and alternative medicine treatments for common skin diseases: A systematic review and meta-analysis JAAD Int · PMID 34409356 · DOI |
Systematic review meta analysis |
40 studies of complementary treatments in acne, atopic dermatitis and psoriasis | Complementary and alternative treatments (mixed) · vs Controls in each study |
For psoriasis the pooled PASI results were SMD 3.04 (CI -0.35 to 6.43) and 5.16 (CI -0.52 to 10.85); both ranges include no effect. The authors conclude there is insufficient evidence to support or recommend complementary treatments for acne, atopic dermatitis and psoriasis. See results Methods, limits and fundingOutcomes: PASI score in psoriasis and other skin scores Limitations: Differences in study design, size, outcome measures and treatment length limit the findings. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Kabat-Zinn 1998 Influence of a mindfulness meditation-based stress reduction intervention on rates of skin clearing in patients with moderate to severe psoriasis undergoing phototherapy (UVB) and photochemotherapy (PUVA) Psychosom Med · PMID 9773769 · DOI |
Randomised controlled trial |
37 37 people with moderate to severe psoriasis about to start UVB or PUVA light treatment |
Mindfulness meditation-based stress reduction by audiotape during light treatments · vs Light treatments alone |
The tape group reached the halfway point (p = 0.013) and the clearing point (p = 0.033) faster than the no-tape group for both UVB and PUVA. Faster clearing, p = 0.013 and 0.033 Methods, limits and fundingOutcomes: Time to skin clearing milestones Limitations: Only 37 people, 1998, no blinding of participants; the clinic nurses who assessed some outcomes were not blinded. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Ko 2019 Lifestyle changes for treating psoriasis Cochrane Database Syst Rev · PMID 31309536 · DOI |
Systematic review meta analysis |
1163 10 RCTs (1,163 people); 6 trials of low-calorie diet in 499 obese people |
Lifestyle changes: low-calorie diet, diet plus exercise, walking, education · vs Usual care, information only, no intervention or medical therapy alone |
Against usual care, strict calorie restriction may lead to PASI 75 more often (RR 1.66, CI 1.07 to 2.58; 2 trials, 323 people; low-quality evidence). The combined diet and exercise programme (303 people) probably improves severity, but the range includes little or no difference (PASI 75 RR 1.28, CI 0.83 to 1.98). No trials of alcohol abstinence or smoking cessation were found. Five trials had high risk of performance bias. PASI 75 RR 1.66 (diet versus usual care) Methods, limits and fundingOutcomes: Severity (PASI 75), quality of life, BMI, adherence Limitations: Low to moderate quality evidence; small numbers; results apply mainly to obese participants. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Lin 2018 Comparison of indirubin concentrations in indigo naturalis ointment for psoriasis treatment: a randomized, double-blind, dosage-controlled trial Br J Dermatol · PMID 28815560 · DOI |
Randomised controlled trial |
Adults with chronic plaque psoriasis over 1 year, under 20 percent of body surface area | Lindioil (refined indigo naturalis) ointment at four indirubin strengths, twice daily for 8 weeks · vs The other three strengths (dose-controlled, no placebo) |
PASI fell by 69.2 percent with the strongest ointment (200 micrograms per gram), versus 63.1, 53.4 and 50.3 percent for the others (P = 0.0445). PASI 75 was reached by 57 percent and PASI 90 by 30 percent of the top group. No severe treatment-related adverse events in 20 weeks. PASI -69.2 percent (strongest ointment) Methods, limits and fundingOutcomes: Percent change in PASI at week 8; PASI 75 and 90 Limitations: No placebo group, so it compares strengths of the ointment only; the abstract does not give the number of participants. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Morrow 2026 Impact of weight-loss interventions on psoriasis severity: A systematic review and meta-analysis J Eur Acad Dermatol Venereol · PMID 41416383 · DOI |
Systematic review meta analysis |
1145 13 RCTs (1,145 people) in adults with psoriasis; 11 advised diet changes, 4 included exercise, 3 used weight-loss medicines |
Weight-loss interventions · vs Usual care or lower-intensity weight-loss intervention |
Average weight change -6.7 kg. PASI fell more: MD -2.5 (CI -3.8 to -1.1, I2 85 percent). PASI 75 more likely (RR 1.6, CI 1.1 to 2.2). No clear effect for PASI 50 or PASI 100 (few studies). DLQI improved: MD -5.0 (CI -9.7 to -0.3). The authors describe the evidence as high certainty. PASI MD -2.5; PASI 75 RR 1.6 Methods, limits and fundingOutcomes: PASI, PASI 50/75/100 and DLQI Limitations: High inconsistency between trials (I2 85 percent for PASI); some trials used weight-loss medicines, not only diet. Funding and conflicts: Three grants are recorded in the PubMed entry; funders not read. Read: abstract |
| Peinemann 2020 Indoor salt water baths followed by artificial ultraviolet B light for chronic plaque psoriasis Cochrane Database Syst Rev · PMID 32368795 · DOI |
Systematic review meta analysis |
8 RCTs (6 with 2,035 people, 2 within-person studies) in adults with chronic plaque psoriasis, all in Europe | Indoor salt water baths followed by artificial UVB light · vs UVB light alone or other treatments |
Salt bath plus UVB may improve psoriasis compared with UVB alone (PASI 75 risk ratio 1.71, CI 1.24 to 2.35; 278 people; low-certainty evidence). It may make little difference to side effects that caused withdrawal (RR 0.96; low-certainty). The two trials with the main result were from the same group and unblinded for assessors. PASI 75 RR 1.71 Methods, limits and fundingOutcomes: PASI 75 and adverse events Limitations: Low-certainty evidence; three of eight trials were sponsored by spa or salt companies. Funding and conflicts: Commercial spa or salt companies sponsored three of eight included trials; the German Spas Association funded one contributing trial. Read: abstract |
| Perez-Bootello 2025 Mediterranean Diet and Patients With Psoriasis: The MEDIPSO Randomized Clinical Trial JAMA Dermatol · PMID 40991259 · DOI |
Randomised controlled trial |
38 38 adults with mild to moderate psoriasis (PASI 2 to 10) on stable topical therapy, Madrid, Spain |
16-week dietitian-guided Mediterranean diet programme with weekly extra virgin olive oil · vs Standard low-fat diet advice without dietitian supervision |
PASI change -3.4 in the Mediterranean diet group versus 0.0 in controls (difference -3.4, CI -4.8 to -2.0). 9 of 19 people (47.4 percent) in the diet group reached PASI 75 versus none of the controls. HbA1c also fell more in the diet group. PASI difference -3.4 Methods, limits and fundingOutcomes: Change in PASI at week 16 Limitations: Single centre, 38 people, open-label with only the evaluator blinded, and the control group had no dietitian support, so attention may account for some of the difference. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Syed 1996 Management of psoriasis with Aloe vera extract in a hydrophilic cream: a placebo-controlled, double-blind study Trop Med Int Health · PMID 8765459 · DOI |
Randomised controlled trial |
60 60 adults aged 18 to 50 with slight to moderate chronic plaque psoriasis |
Aloe vera extract 0.5 percent in a hydrophilic cream on the skin, up to 4 weeks of active treatment · vs Placebo cream |
The report says 25 of 30 (83.3 percent) in the aloe group were cured versus 2 of 30 (6.6 percent) with placebo. No adverse drug-related symptoms. Cure 83.3 percent versus 6.6 percent Methods, limits and fundingOutcomes: Cure and PASI Limitations: Published in 1996 with an unusual definition of healed; a later review rated the methods as variable,. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Theodoridis 2021 Effectiveness of oral vitamin D supplementation in lessening disease severity among patients with psoriasis: A systematic review and meta-analysis of randomized controlled trials Nutrition · PMID 33183899 · DOI |
Systematic review meta analysis |
4 RCTs in the review, 3 pooled | Oral vitamin D supplementation · vs Placebo |
PASI fell by 0.92 at 6 months (CI -1.72 to -0.11), but after a statistical adjustment for few studies the result was not significant (CI -2.21 to 0.38). The authors say a favourable effect could not be verified. MD -0.92, not robust Methods, limits and fundingOutcomes: PASI Limitations: Only 3 small trials pooled. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Timis 2021 Mind-Body Interventions as Alternative and Complementary Therapies for Psoriasis: A Systematic Review of the English Literature Medicina (Kaunas) · PMID 33922733 · DOI |
Systematic review |
Articles on acupuncture (12), cupping (9), meditation, hypnosis or psychotherapy (27), and climatotherapy or balneotherapy (34) in psoriasis | Mind-body and spa-based therapies · vs Varies |
The authors found a lack of evidence in the English literature to support acupuncture, that cupping was mostly described with the Koebner phenomenon (new patches after skin injury) and clinical worsening, that stress-management therapies showed promising results, and that climatotherapy and balneotherapy were effective for clinical improvement. See results Methods, limits and fundingOutcomes: Skin improvement Limitations: A narrative review of mixed study types; the abstract gives no numbers. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Upala 2015 Effect of lifestyle weight loss intervention on disease severity in patients with psoriasis: a systematic review and meta-analysis Int J Obes (Lond) · PMID 25920774 · DOI |
Systematic review meta analysis |
878 7 RCTs (878 people) in overweight or obese adults with psoriasis; 5 pooled |
Diet and exercise weight-loss programmes · vs Controls |
Greater PASI fall with weight loss: mean difference -2.49 (CI -3.90 to -1.08). More people reached PASI 75: odds ratio 2.92 (CI 1.39 to 6.13). PASI -2.49; PASI 75 OR 2.92 Methods, limits and fundingOutcomes: PASI change and PASI 75 Limitations: Few trials; the authors say more and larger RCTs are needed. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Yang 2019 Effects of fish oil supplement on psoriasis: a meta-analysis of randomized controlled trials BMC Complement Altern Med · PMID 31805911 · DOI |
Systematic review meta analysis |
625 13 RCTs (625 people) of fish oil in psoriasis; 3 RCTs (337 people) had usable data |
Fish oil supplements · vs Placebo or controls |
Pooled PASI difference -0.28 (CI -1.74 to 1.19), not significant. The authors conclude that current evidence does not support fish oil supplements for psoriasis. MD -0.28 (no significant effect) Methods, limits and fundingOutcomes: PASI Limitations: Only 3 trials could be pooled. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| Zhang 2022 Efficacy and safety of curcumin in psoriasis: preclinical and clinical evidence and possible mechanisms Front Pharmacol · PMID 36120325 · DOI |
Systematic review meta analysis |
26 studies: 7 clinical RCTs and 19 preclinical (animal and cell) studies | Curcumin alone or with conventional treatment · vs Controls |
In the clinical trials, curcumin alone or combined improved PASI compared with controls (standardised mean difference -0.83, p = 0.02). In mice and cells it lowered inflammatory signals. The authors say efficacy and safety have not been confirmed. Standardised MD -0.83 Methods, limits and fundingOutcomes: PASI and inflammatory markers Limitations: Mixed oral, topical and combination uses; the reported confidence interval in the abstract appears inconsistent with the p value, so treat the number with caution. Funding and conflicts: No funding or conflict statement in the record read. Read: abstract |
| s-nccih-aloe NCCIH: Aloe vera (last updated February 2025) · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-nhs-psoriasis NHS: Psoriasis (last reviewed 10 March 2026) · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-nhs-psoriasis-treatment NHS: Psoriasis treatment (last reviewed 10 March 2026) · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text | ||
| s-niams-psoriasis NIAMS: Psoriasis (last reviewed October 2023) · Source |
Health agency n/a |
Methods, limits and fundingRead: full-text |
What we do not know yet
- No large randomised trial of the Mediterranean diet in psoriasis was read; the one trial found has 38 people.
- No trial of stopping smoking or alcohol in people who already have psoriasis was found.
- Primary trials of curcumin were not read, only reviews.
- No head-to-head trial of any natural option against standard psoriasis care was read.
- Most trials are small and short, so long-term safety is not known.
How new research is added
New studies are found by a saved PubMed search and placed in a review queue before the page changes.
Lab markers
What changed in blood or saliva tests during trials. A changed number is not the same as feeling or being healthier, and we give no "normal ranges".
Other 3
Psoriasis Area and Severity Index (PASI)
Fell with weight loss, Mediterranean diet and topical indigo naturalis in trials in trials
A score from 0 to 72 combining how much skin is affected and how red, thick and scaly the patches are.
Moderate certaintyResults and what it means
Why it was measured
The main way trials measure whether psoriasis has improved.
Statistical vs. clinical meaning
A standard clinical score, but different trials use different time points.
PASI 75 response
More likely with weight loss, indigo naturalis and salt bath plus UVB in trials
The share of people whose PASI score falls by at least 75 percent from the start.
Moderate certaintyResults and what it means
Why it was measured
A common trial target meaning most of the disease has cleared.
Statistical vs. clinical meaning
Easier to understand than average scores, but small trials give wide ranges.
Dermatology Life Quality Index (DLQI)
Improved with weight loss in trials
A questionnaire on how much a skin condition affects daily life, from 0 to 30.
Low certaintyResults and what it means
Why it was measured
Psoriasis affects sleep, mood, work and social life, not only the skin.
Statistical vs. clinical meaning
Patient-reported, with very high differences between trials (I2 96 percent).
| Study | Result | People | Product |
|---|---|---|---|
| 14 | Weight loss: MD -5.0 (CI -9.7 to -0.3). | 364 people in 7 comparisons | Weight loss |
Safety
What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.
Main points to know 8
- See a GP if you have symptoms, treatment is not working, or joints keep hurting. The NHS says to see a GP if you have symptoms of psoriasis, your treatment is not working or causes side effects, or you have joint pain, stiffness or swelling that keeps coming back. NIAMS adds that untreated psoriatic arthritis can cause irreversible joint damage, so symptoms should be raised soon. Health agency guidance 24 26
- Emergency: rapidly spreading red skin or pus-filled bumps. The NHS says to call emergency services or go to the emergency department if the skin quickly turns red with joined-up pus-filled bumps, if patches on the feet turn yellow-brown and fill with pus, or if fingers or toes get red, scaly, pus-filled bumps. Warning signs include a fast heartbeat, high temperature, or feeling hot, cold or shivery. It advises not to drive yourself. These may be serious pustular or erythrodermic forms, which NIAMS describes as serious. Health agency guidance 24 26
- Do not replace prescribed treatment with a natural option. The reviews read found complementary treatments to be small-trial evidence at best, and the 2021 meta-analysis concluded there was insufficient evidence to recommend them. Diet and weight changes are advised by the National Psoriasis Foundation only alongside standard medical therapy. Tell your clinician about everything you use. Systematic review and guideline 10 7
- Psoriasis and mood. The NHS says mental health support is available and that a GP can refer you to a mental health specialist if psoriasis affects your mental health. NIAMS lists anxiety and depression among linked conditions. If you have thoughts of harming yourself, contact a doctor or your local emergency services or crisis line right away. Health agency guidance 24 26
- Emollient fire safety. The NHS warns that clothing and bedding that have emollients on them can catch fire more easily, so keep away from smoking and naked flames, and not to share emollients or dip fingers into tubs. Health agency guidance 25 24
- Pregnancy and breastfeeding. The NHS says pregnancy can make symptoms worse and that treatment may need to be changed because some psoriasis medicines are harmful, so speak to a doctor or pharmacist if pregnant or trying to conceive. NCCIH says aloe taken by mouth in any form may be unsafe in pregnancy and breastfeeding. No source read covers pregnancy safety for curcumin, indigo naturalis, Mahonia or fish oil, so ask before using them. Health agency guidance 24 23
- Cupping and skin injury can cause new patches. A 2021 review reports that cupping was mostly described with the Koebner phenomenon (new patches appearing where skin is injured) and clinical worsening. The NHS lists skin injury and sunburn among triggers. Systematic review and health agency guidance 19 24
- Aloe and curcumin products by mouth. NCCIH says aloe leaf extract by mouth has been linked to cases of acute hepatitis and aloe latex can cause cramps and diarrhoea, and that overuse of latex may increase side effects of digoxin-type heart medicines. For curcumin, the reviews read describe no serious problems in the trials but note small studies and that safety is not confirmed. Health agency guidance and systematic review 23 22
Side effects 5
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Skin burning, itching or rash from topical plant products | Under 1 percent with the Mahonia cream; occasional with aloe gel (NCCIH); no rate for indigo naturalis. | Mostly minor | Randomised trial and health agency guidance 1 23 5 |
| Severe itch after a Dead Sea salt soak | One participant in a within-person study of the Cochrane review. | Not graded | Systematic review 15 |
| Worsening or new patches after cupping | Described in most reports; no rate in the abstract. | Not graded | Systematic review 19 |
| Aloe by mouth: stomach cramps, diarrhoea, rare hepatitis | No rates given on the NCCIH page. | Cramps and diarrhoea mild; hepatitis serious | Health agency guidance 23 |
| No adverse effects with oral vitamin D in one trial | None registered over 4 months in 122 people. | No effects to grade | Randomised trial 9 |
Medicines and supplements 3
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Prescription psoriasis treatments prescription | No study found. | No interaction study of the natural options with psoriasis medicines was read. Absence of a study is not proof of safety. | Absence of evidence Not enough evidence 25 | Tell your doctor or pharmacist about every supplement, herb or skin product you use, as some psoriasis treatments affect the liver or immune system. |
| Blood thinners (fish oil, curcumin) prescription | Not covered in the sources read. | The sources read do not test this. Whether omega-3 or curcumin affect bleeding was not verified in the sources read. | Absence of evidence Not enough evidence 21 22 | Ask a pharmacist before taking either if you use a blood thinner. |
| Digoxin-type heart medicines (aloe latex) prescription | NCCIH says overuse of aloe latex may increase side effects of cardiac glycosides such as digoxin. | Applies to aloe latex taken by mouth, not aloe gel on the skin. | Health agency guidance Low certainty 23 | Talk to a health care provider before using aloe if you take any medicine. |
Who should check first 5
| Situation | Advice | Evidence |
|---|---|---|
| Pregnancy, trying to conceive or breastfeeding | Speak to a doctor or pharmacist before any psoriasis treatment, since some medicines are harmful. Aloe by mouth may be unsafe (NCCIH). Safety of the other natural options was not found. | Health agency guidance 24 23 |
| Moderate to severe, widespread, pustular or erythrodermic psoriasis | Do not self-treat. These forms need a doctor; NIAMS says moderate and severe disease may need pills, injections or light treatment. | Health agency guidance 26 24 |
| Joint pain, stiffness or swelling | See a GP, because this may be psoriatic arthritis, which NIAMS says can cause irreversible joint damage if untreated. | Health agency guidance 26 24 |
| Overweight or diabetes and wanting to lose weight quickly | Make diet changes with a clinician or dietitian, since the NPF advises dietary change only alongside standard care. | Guideline 7 |
| Known allergy to a plant product | Stop the product if skin burns, itches or comes up in a rash. | Health agency guidance 23 1 |
Overdose, product quality and regulators
| Body | Action | Date |
|---|---|---|
| NHS (England) (United Kingdom) | Describes psoriasis as not curable but treatable; lists emollients, vitamin D preparations, steroid creams and coal tar, with light therapy and other medicines for more severe disease; advises a balanced diet, exercise, stress reduction, limiting alcohol and stopping smoking; sets out emergency signs. source | 2026-03-10 |
| American Academy of Dermatology and National Psoriasis Foundation (United States) | Joint 2021 guideline on topical therapy and alternative medicine, and 2018 NPF dietary recommendations: strong for weight reduction in overweight and obese people, weak for gluten-free diet only with positive serology. source | 2021 |
When to get medical help
- Skin quickly turning red with joined-up pus-filled bumps, especially with fever, fast heartbeat or feeling hot, cold or shivery: call emergency services; do not drive yourself.
- Patches on the feet turning yellow-brown and filling with pus, or red scaly pus-filled bumps on fingertips and toes: emergency care.
- Joint pain, stiffness or swelling that keeps coming back: see a GP soon.
- Treatment not working, or causing side effects: see a GP.
- Low mood, anxiety or thoughts of self-harm: contact a doctor or your local emergency or crisis service right away.
- A rash, swelling or trouble breathing after a product: stop it and seek medical help.
Stop using the product and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.
General information only, not medical advice. Ask a clinician or pharmacist before use, especially with medicines, in pregnancy or with a health condition. See the Natural Remedy Safety guide.
Frequently asked questions
What is psoriasis?
What are the types of psoriasis?
NIAMS lists plaque, guttate, pustular, inverse and erythrodermic psoriasis. Plaque is the most common; erythrodermic is rare but serious.
What triggers a psoriasis flare-up?
Can psoriasis be cured?
The NHS says it cannot be cured, but treatments can manage symptoms.
What does established psoriasis care look like?
The NHS lists emollients, vitamin D preparations, steroid creams and coal tar, with light therapy and other medicines for more severe disease. A GP may refer you to a dermatologist.
Does losing weight help psoriasis?
Does the Mediterranean diet help psoriasis?
One 2025 trial of 38 adults found a dietitian-guided Mediterranean diet lowered PASI by 3.4 points more than standard low-fat advice over 16 weeks. It is a small trial and needs confirming.
Does curcumin or turmeric help psoriasis?
Does fish oil help psoriasis?
Does vitamin D by mouth help psoriasis?
Does aloe vera help psoriasis?
When should I see a doctor about psoriasis?
The NHS says to see a GP if you have symptoms, treatment is not working or causes side effects, or joint pain, stiffness or swelling keeps returning. Use emergency services if the skin quickly turns red with joined-up pus-filled bumps.
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- Written by
- AlternativeMed editorial team. Research compiled with AI assistance, then checked against PubMed records.
- Medical review
- None. This page has not been reviewed by a physician or pharmacist.
- First published
- 2026-10-31
- Last substantive update
- 2026-10-31
- How we research
- We searched PubMed, read the abstract of every review, trial and guideline cited, and read the NHS, NIAMS and NCCIH pages through a tool that summarises pages. Certainty ratings are the compiler's own reading unless a review gives its own grade.
- How we rate evidence
- See "How we rate evidence" in the Evidence tab.
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Sources 26
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
- Bernstein S, Donsky H, Gulliver W et al.. Treatment of mild to moderate psoriasis with Reliéva, a Mahonia aquifolium extract--a double-blind, placebo-controlled study. Am J Ther. 2006. PMID 16645428. DOI 10.1097/00045391-200603000-00007. (abstract)
- Chen D, Ye G, Yang J et al.. Smoking, alcohol consumption, and psoriasis risk: a systematic review and dose-response meta-analysis of observational studies. Front Public Health. 2026. PMID 42326923. DOI 10.3389/fpubh.2026.1840932. (abstract)
- Cheng HM, Wu YC, Wang Q et al.. Clinical efficacy and IL-17 targeting mechanism of Indigo naturalis as a topical agent in moderate psoriasis. BMC Complement Altern Med. 2017. PMID 28865459. DOI 10.1186/s12906-017-1947-1. (abstract)
- Clark CCT, Taghizadeh M, Nahavandi M et al.. Efficacy of ω-3 supplementation in patients with psoriasis: a meta-analysis of randomized controlled trials. Clin Rheumatol. 2019. PMID 30778861. DOI 10.1007/s10067-019-04456-x. (abstract)
- Deng S, May BH, Zhang AL et al.. Plant extracts for the topical management of psoriasis: a systematic review and meta-analysis. Br J Dermatol. 2013. PMID 23909714. DOI 10.1111/bjd.12557. (abstract)
- Elmets CA, Korman NJ, Prater EF et al.. Joint AAD-NPF Guidelines of care for the management and treatment of psoriasis with topical therapy and alternative medicine modalities for psoriasis severity measures. J Am Acad Dermatol. 2021. PMID 32738429. DOI 10.1016/j.jaad.2020.07.087. (abstract)
- Ford AR, Siegel M, Bagel J et al.. Dietary Recommendations for Adults With Psoriasis or Psoriatic Arthritis From the Medical Board of the National Psoriasis Foundation: A Systematic Review. JAMA Dermatol. 2018. PMID 29926091. DOI 10.1001/jamadermatol.2018.1412. (abstract)
- Gamret AC, Price A, Fertig RM et al.. Complementary and Alternative Medicine Therapies for Psoriasis: A Systematic Review. JAMA Dermatol. 2018. PMID 30193251. DOI 10.1001/jamadermatol.2018.2972. (abstract)
- Jenssen M, Furberg AS, Jorde R et al.. Effect of Vitamin D Supplementation on Psoriasis Severity in Patients With Lower-Range Serum 25-Hydroxyvitamin D Levels: A Randomized Clinical Trial. JAMA Dermatol. 2023. PMID 36988936. DOI 10.1001/jamadermatol.2023.0357. (abstract)
- Jones VA, Patel PM, Wilson C et al.. Complementary and alternative medicine treatments for common skin diseases: A systematic review and meta-analysis. JAAD Int. 2021. PMID 34409356. DOI 10.1016/j.jdin.2020.11.001. (abstract)
- Kabat-Zinn J, Wheeler E, Light T et al.. Influence of a mindfulness meditation-based stress reduction intervention on rates of skin clearing in patients with moderate to severe psoriasis undergoing phototherapy (UVB) and photochemotherapy (PUVA). Psychosom Med. 1998. PMID 9773769. DOI 10.1097/00006842-199809000-00020. (abstract)
- Ko SH, Chi CC, Yeh ML et al.. Lifestyle changes for treating psoriasis. Cochrane Database Syst Rev. 2019. PMID 31309536. DOI 10.1002/14651858.CD011972.pub2. (abstract)
- Lin YK, See LC, Huang YH et al.. Comparison of indirubin concentrations in indigo naturalis ointment for psoriasis treatment: a randomized, double-blind, dosage-controlled trial. Br J Dermatol. 2018. PMID 28815560. DOI 10.1111/bjd.15894. (abstract)
- Morrow S, Hawkins P, Griffiths CEM et al.. Impact of weight-loss interventions on psoriasis severity: A systematic review and meta-analysis. J Eur Acad Dermatol Venereol. 2026. PMID 41416383. DOI 10.1111/jdv.70247. (abstract)
- Peinemann F, Harari M, Peternel S et al.. Indoor salt water baths followed by artificial ultraviolet B light for chronic plaque psoriasis. Cochrane Database Syst Rev. 2020. PMID 32368795. DOI 10.1002/14651858.CD011941.pub2. (abstract)
- Perez-Bootello J, Berna-Rico E, Abbad-Jaime de Aragon C et al.. Mediterranean Diet and Patients With Psoriasis: The MEDIPSO Randomized Clinical Trial. JAMA Dermatol. 2025. PMID 40991259. DOI 10.1001/jamadermatol.2025.3410. (abstract)
- Syed TA, Ahmad SA, Holt AH et al.. Management of psoriasis with Aloe vera extract in a hydrophilic cream: a placebo-controlled, double-blind study. Trop Med Int Health. 1996. PMID 8765459. DOI 10.1046/j.1365-3156.1996.d01-91.x. (abstract)
- Theodoridis X, Grammatikopoulou MG, Stamouli EM et al.. Effectiveness of oral vitamin D supplementation in lessening disease severity among patients with psoriasis: A systematic review and meta-analysis of randomized controlled trials. Nutrition. 2021. PMID 33183899. DOI 10.1016/j.nut.2020.111024. (abstract)
- Timis TL, Florian IA, Mitrea DR et al.. Mind-Body Interventions as Alternative and Complementary Therapies for Psoriasis: A Systematic Review of the English Literature. Medicina (Kaunas). 2021. PMID 33922733. DOI 10.3390/medicina57050410. (abstract)
- Upala S, Sanguankeo A. Effect of lifestyle weight loss intervention on disease severity in patients with psoriasis: a systematic review and meta-analysis. Int J Obes (Lond). 2015. PMID 25920774. DOI 10.1038/ijo.2015.64. (abstract)
- Yang SJ, Chi CC. Effects of fish oil supplement on psoriasis: a meta-analysis of randomized controlled trials. BMC Complement Altern Med. 2019. PMID 31805911. DOI 10.1186/s12906-019-2777-0. (abstract)
- Zhang S, Wang J, Liu L et al.. Efficacy and safety of curcumin in psoriasis: preclinical and clinical evidence and possible mechanisms. Front Pharmacol. 2022. PMID 36120325. DOI 10.3389/fphar.2022.903160. (abstract)
- . NCCIH: Aloe vera (last updated February 2025). . . (full-text)
- . NHS: Psoriasis (last reviewed 10 March 2026). . . (full-text)
- . NHS: Psoriasis treatment (last reviewed 10 March 2026). . . (full-text)
- . NIAMS: Psoriasis (last reviewed October 2023). . . (full-text)
