Alpha-Lipoic Acid
Alpha-lipoic acid (ALA) is not omega-3 ALA. What reviews found for diabetic nerve symptoms and blood sugar, the intravenous versus oral difference, and safety cautions.
Content last updated . This page has not been medically reviewed.
What is Alpha-lipoic acid good for?
What the body uses it for, and how strong the evidence is. A normal job in the body is not proof that extra supplements add benefit; each card says which.
Antioxidant activity
Lab or animal research onlyAlpha-lipoic acid is a compound the body makes. In lab settings it behaves as an antioxidant and has anti-inflammatory properties.
Supplements: Lab antioxidant behaviour does not show that taking it as a supplement prevents disease or slows ageing.
Diabetic nerve symptoms (by mouth)
Preliminary or mixedIn people with diabetic neuropathy, some trials found less pain, burning and tingling in the feet; others found no clear change.
Supplements: Mixed: NCCIH cites a review in which 3 of 8 studies found improvement and 5 did not. Trials are short.
Diabetic nerve symptoms (intravenous)
Preliminary or mixedGiven by IV in a medical setting for a few weeks, it was linked to better nerve test results and symptoms in trials.
Supplements: Promising but limited; IV results should not be carried over to capsules.
Blood sugar markers in type 2 diabetes
Preliminary or mixedReviews disagree on whether it lowers blood sugar; changes found were small.
Supplements: No good evidence of meaningful benefit; NCCIH cites a review finding it no better than placebo for blood sugar.
Diabetic eye and kidney complications
Not enough evidenceA 2-year trial found no significant difference in diabetic macular edema, and a review found kidney function did not improve.
Supplements: No good evidence of benefit.
Weight, ageing and general antioxidant protection
Not enough evidenceClaims for these uses are common, but no adequate clinical outcome trials were found.
Supplements: Marketing claim without trial support in the sources read.
Use in pregnancy
Not enough evidenceNo official guidance was found. A 2014 narrative review called early data promising, which is not proof of safety.
Supplements: Not established; ask a clinician.
Connected topics
Open a group to see how each topic connects and how strong the evidence is.
Health goals (2)
- Blood Sugar BalancePreliminary or mixed
Reviews of trials in type 2 diabetes disagree: one found lower fasting glucose and HbA1c, another found the changes too small to matter clinically.
- Cellular ProtectionLab or animal research only
Alpha-lipoic acid shows antioxidant behaviour in the lab. This does not show that taking it as a supplement protects cells or prevents disease.
Body systems (3)
- Nervous SystemPreliminary or mixed
Studied for nerve symptoms (pain, burning, tingling in the feet) in diabetes. Results are mixed by mouth and more favourable but lower quality by IV; NCCIH calls the possible benefit weak.
- Blood Sugar SupportPreliminary or mixed
Reviews disagree on whether it lowers blood sugar markers, and the average changes were small. Rarely, it has been linked to low blood sugar through insulin autoimmune syndrome.
- Pain & InflammationPreliminary or mixed
Some trials report less neuropathy pain in diabetes, but reviews are mixed and NCCIH calls the evidence weak.
Body parts (2)
- Nervous SystemPreliminary or mixed
Peripheral nerve symptoms in diabetes are the main studied use; results are mixed and trials are short.
- CellsLab or animal research only
Antioxidant activity is shown in lab settings; benefit to cells in people taking supplements is not established.
Functional actions (4)
- AntioxidantLab or animal research only
A 2025 review describes antioxidant and anti-inflammatory properties. Lab antioxidant activity is not proof that the supplement prevents disease.
- Nervous System SupportPreliminary or mixed
Symptom scores improved in several diabetic neuropathy trials, not in others; long-term nerve protection is unknown.
- Blood Sugar RegulationPreliminary or mixed
Mixed review findings: lower HbA1c and fasting glucose in one meta-analysis, but changes below clinically important thresholds in another and no better than placebo in a third.
- Pain ReliefPreliminary or mixed
NCCIH describes weak evidence of a possible benefit for neuropathy pain; results are mixed and not a treatment plan.
Root causes (1)
- Blood Sugar ImbalancePreliminary or mixed
Studied in people with type 2 diabetes; effects on blood sugar markers were small and reviews disagree.
Biomarkers (2)
- Blood GlucoseDocumented risk
Fasting glucose was lower in one meta-analysis, but changes were small. Rare low blood sugar episodes from insulin autoimmune syndrome have been linked to it, so people on diabetes medicines should ask a clinician first.
- HbA1cPreliminary or mixed
One meta-analysis of 41 articles found lower HbA1c; a dose-response analysis found oral effects below clinically important thresholds.
Conditions & symptoms (3)
- Diabetic Peripheral NeuropathyPreliminary or mixed
Some trials show better symptom scores for nerve symptoms in diabetes; reviews are mixed and NCCIH calls the evidence weak.
- HypoglycemiaDocumented risk
Rare low blood sugar episodes have been linked to alpha-lipoic acid through insulin autoimmune syndrome.
- Diabetes Mellitus, Non-Insulin-DependentPreliminary or mixed
Studied for blood sugar markers in type 2 diabetes with conflicting results. It should not replace diabetes treatment.
Documented risks and interactions (2)
- Low blood sugar through insulin autoimmune syndrome. Rarely, it has been linked to a condition that causes episodes of low blood sugar.
- Common side effects. Headache, heartburn, nausea and vomiting are the most common side effects; nausea, vomiting and vertigo rose with dose in one oral trial.
Not the same as omega-3 "ALA"
Alpha-lipoic acid (ALA, also called lipoic acid or thioctic acid) is a compound the body makes. Alpha-linolenic acid, also abbreviated ALA, is a plant omega-3 fat and is a different compound; see omega fatty acids explained. Everything below is about alpha-lipoic acid.Overview
A 2025 review describes alpha-lipoic acid as an endogenously synthesized compound with antioxidant and anti-inflammatory properties. [1] "Antioxidant" describes lab behavior; it does not by itself mean a supplement helps a person. We did not read an official recommended intake or upper limit for alpha-lipoic acid, so none is given. Evidence labels are explained on Antioxidants Explained.Evidence by use
| Use | What the sources found | Label |
|---|---|---|
| Diabetic nerve symptoms, by mouth | A 2023 meta-analysis of 10 randomized trials (1,242 patients) found better total symptom scores and global satisfaction than placebo, but not for several other measures, including nerve conduction and vibration threshold. [2] NCCIH, summarizing a 2022 review of 8 studies, notes 3 found improvement and 5 did not. [3] | Mixed |
| Diabetic nerve symptoms, intravenous (IV) | A meta-analysis of 15 trials of 300 to 600 mg IV a day for 2 to 4 weeks reported better nerve conduction and symptoms, but most trials were of poor quality. [4] | Promising but limited |
| Blood sugar in type 2 diabetes | Conflicting: one meta-analysis of 41 articles found lower fasting glucose and HbA1c. [5] A later dose-response analysis of 16 trials found the changes were below clinically important thresholds. [6] NCCIH cites a 2019 review finding no better than placebo for blood sugar, cholesterol or triglycerides. [3] | Mixed |
| Diabetic eye and kidney complications | NCCIH describes a 2011 study of 467 people with type 2 diabetes (600 mg a day for 2 years) with no significant difference in diabetic macular edema, and a 2022 review in which supplementation did not improve kidney dysfunction. [3] | No good evidence of benefit |
| Weight, aging, general "antioxidant protection" | Proper evidence not found. We searched PubMed and the NCCIH diabetes fact sheet and found no adequate clinical outcome trials for these. | Marketing claim |
For the detail on nerve and blood sugar trials, see alpha-lipoic acid for diabetic neuropathy and blood sugar. NCCIH's overall summary is that alpha-lipoic acid "might be helpful" for diabetic neuropathy pain but that most studies are limited and no clear conclusion can be drawn. [3]
Forms and amounts
Intravenous and oral results should not be transferred to each other: IV treatment is given in a medical setting. [4] Lipoic acid exists in R and mixed (racemic) forms; see R-lipoic acid vs racemic alpha-lipoic acid. Amounts in trials (for example 600, 1,200 and 1,800 mg a day by mouth for 5 weeks in one trial) are study amounts, not advice. [7] A 2025 review noted a lack of clinical trials of injectable forms and of studies in vulnerable groups. [1]Frequently asked questions
Is alpha-lipoic acid the same as omega-3 ALA?
No. Alpha-linolenic acid is a plant omega-3 fat; alpha-lipoic acid is a different compound.
Does alpha-lipoic acid help diabetic neuropathy?
Results are mixed by mouth and more favorable but lower quality by IV. [2][4] NCCIH calls the possible benefit weak. [3]
Does it lower blood sugar?
Reviews disagree, and one found the effects too small to matter clinically. [5][6]
Can it cause low blood sugar?
Rare cases of insulin autoimmune syndrome, which causes hypoglycemia, have been linked to alpha-lipoic acid supplements. [8] If you notice episodes of low blood sugar, speak to a clinician.
Is it safe in pregnancy?
Proper evidence not found from an official body in the sources we read. A 2014 narrative review called the data promising, which is not proof of safety. [9] Ask your clinician.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety in brief
Also ask a clinician before use if you are pregnant or breastfeeding, give it to a child, have kidney or liver disease, or have surgery planned. See pregnancy, breastfeeding and children, surgery and kidney or liver disease, medication interactions and reading supplement labels.
Numbness, burning or pain in the feet needs a medical assessment, not self-treatment. NCCIH stresses not replacing medical treatment for diabetes with an unproven health product. [3]
References
- Carnib BL, et al. Therapeutic applications of alpha-lipoic acid: a review of clinical and preclinical evidence (1998-2024). Biomed Pharmacother 2025. Read 2026-10-22.
- Hsieh RY, et al. Effects of oral alpha-lipoic acid treatment on diabetic polyneuropathy: a meta-analysis and systematic review. Nutrients 2023. Read 2026-10-22.
- Diabetes and Dietary Supplements: What You Need To Know. National Center for Complementary and Integrative Health (US). Read 2026-10-22.
- Han T, et al. A systematic review and meta-analysis of α-lipoic acid in the treatment of diabetic peripheral neuropathy. Eur J Endocrinol 2012. Read 2026-10-22.
- Rahimlou M, et al. Alpha-lipoic acid (ALA) supplementation effect on glycemic and inflammatory biomarkers: a systematic review and meta-analysis. Clin Nutr ESPEN 2019. Read 2026-10-22.
- Jibril AT, et al. Efficacy and safety of oral alpha-lipoic acid supplementation for type 2 diabetes management: a systematic review and dose-response meta-analysis of randomized trials. Endocr Connect 2022. Read 2026-10-22.
- Ziegler D, et al. Oral treatment with alpha-lipoic acid improves symptomatic diabetic polyneuropathy: the SYDNEY 2 trial. Diabetes Care 2006. Read 2026-10-22.
- Vallianou NG, et al. Alpha-lipoic acid as a trigger of insulin autoimmune syndrome: current evidence, a case-based approach, diagnostic pitfalls, and practical management. Metabol Open 2026. Read 2026-10-22.
- Costantino M, et al. Peripheral neuropathy in obstetrics: efficacy and safety of alpha-lipoic acid supplementation. Eur Rev Med Pharmacol Sci 2014. Read 2026-10-22.