Herbs for Low Mood and Depression: St. John's Wort, Saffron and the Limits of Evidence
What NIH and systematic reviews say about St. John's wort and saffron for low mood and depression, the limits of the evidence, and the serious medicine interactions to know about first.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
If you are in crisis, get help now. If you are in immediate distress or thinking about hurting yourself, you can call, text or chat 988, the 988 Suicide & Crisis Lifeline in the United States, which offers 24-hour confidential support. [1] In an emergency, call 911. The NHS notes that severe depression can make a person feel suicidal. [2]
Safety first, and never a replacement for treatment. NIH says it has been clearly shown that St. John's wort can interact in dangerous, sometimes life-threatening ways with a variety of medicines. [3] NIH also says depression can be a serious illness and that anyone who may have it should consult a health care provider. [3] Do not stop or change a prescribed antidepressant on your own. Ask the prescriber or pharmacist.
How the sources describe depression care
The NHS says depression treatment can involve lifestyle changes, talking therapies and medicine, chosen by how severe the depression is. For mild depression a doctor may suggest watchful waiting and self-help measures, and for moderate to severe depression a combination of talking therapy and antidepressants is often recommended. [2]Plant names
Accepted names in the GBIF plant database: Hypericum perforatum L. (St. John's wort, family Hypericaceae) [4] and Crocus sativus L. (saffron, family Iridaceae). [5] See Plant Names and Botanical Nomenclature for why the Latin name matters.What research found
| Herb | What the source found | Evidence label | Form and population |
|---|---|---|---|
| St. John's wort | NIH says it appears more effective than placebo and as effective as standard antidepressants for mild or moderate depression, but it is uncertain for severe depression or for periods longer than 12 weeks. [3] | Promising, with moderate-certainty evidence for mild to moderate depression | Oral products; adults |
| St. John's wort, systematic review | A 2016 review of 35 trials (6,993 patients) found more treatment responders than placebo and no difference from antidepressants in mild to moderate depression. It noted heterogeneity and little research on severe depression. [6] | Moderate certainty, with caution | Trials of at least 4 weeks; adults with major depressive disorder |
| Saffron | A 2026 review of 34 trials (1,769 adults) found lower self-reported depression and anxiety scores, but no significant effect on clinician-rated depression or anxiety scales. Certainty was rated moderate, with large differences between studies. [7] | Promising but limited | Saffron supplements, 4 weeks or longer; adults |
| Lavender | NIH says small, preliminary reports suggest oral lavender capsules or tea might reduce depression symptoms in some people, and topical lavender does not seem to. [8] | Preliminary | Oral; small samples |
| Chamomile | NIH says preliminary studies suggest a chamomile supplement might help generalized anxiety disorder and associated depression. [9] | Preliminary | Supplement |
| Valerian | NIH says there is not enough evidence to draw conclusions about depression. [10] | Insufficient evidence | Root products |
Adaptogens and mood herbs from other traditions are covered elsewhere. See Adaptogens for Brain Fog and Mood and Adaptogens vs Prescription Treatments for Anxiety and Depression.
Related pages
St. John's Wort, Herbs and Mental Health Conditions: Mania, Psychosis, Epilepsy, and Herbs by Wellness Goal.Frequently asked questions
Is St. John's wort as good as an antidepressant?
For mild to moderate depression, NIH says it appears as effective as standard antidepressants, but it is uncertain for severe depression. [3] It also interacts with many medicines, so ask a clinician before using it. [3]
Can I take St. John's wort with my antidepressant?
NIH says taking it with certain antidepressants or other drugs that affect serotonin may lead to serious serotonin-related side effects. [3] Ask the prescriber or pharmacist first, and do not stop a prescribed medicine on your own.
Does saffron treat depression?
A 2026 review found lower self-reported depression scores but no significant change on clinician-rated scales, and called for high-quality trials. [7]
Does St. John's wort affect birth control pills?
NIH lists birth control pills among the medicines St. John's wort can weaken. [3] Ask a pharmacist or clinician.
What should I do if I am in crisis?
Call, text or chat 988 in the US for the 988 Suicide & Crisis Lifeline, or call 911 in an emergency. [1]
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.
Limits and uncertainty
- The 2016 review said evidence of heterogeneity and a lack of research on severe depression reduce the quality of the evidence. Adverse events were poorly reported, and studies were not designed to assess rare events. [6]
- The saffron review used a measure people rate themselves, and the clinician-rated scales did not change significantly. The authors said high-quality trials are needed. [7]
- A result for one St. John's wort product does not transfer to another product with a different extract.
Safety and who should ask a clinician
- Medicines: NIH says it can weaken the effects of many medicines, including some antidepressants, birth control pills, cyclosporine (used after organ transplant), some seizure medicines, some heart medicines, some HIV drugs, some cancer medicines, warfarin and certain statins. [3]
- Serotonin: taking it with certain antidepressants or other drugs that affect serotonin may increase serotonin-related side effects, which can be serious. [3] See St. John's Wort Interactions, Supplements and Antidepressants and Herbs and Antidepressants: Serotonin Syndrome.
- Pregnancy and breastfeeding: NIH says it may be unsafe in pregnancy because it may increase the risk of birth defects, and breastfed infants can experience colic, drowsiness and lethargy. [3]
- Skin and side effects: large oral amounts or skin use might cause severe skin reactions after sun exposure. Other side effects include diarrhea, dizziness, trouble sleeping, restlessness and skin tingling. [3]
- Liver: a Berlin hospital study judged St. John's wort a possible cause in one of 198 liver injury cases. [11]
Saffron: safety, pregnancy and medicine interactions are not described in the sources we read for this page. Ask a pharmacist, and see the Saffron profile.
Tell every clinician and your pharmacist about any herb you use. See How Interactions Work and St. John's Wort vs Prescription Antidepressants.
References
- National Center for Complementary and Integrative Health (NCCIH). Anxiety and Complementary Health Approaches. Read 2026-10-23.
- NHS (UK). Overview: Depression in adults. Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). St. John’s Wort. Read 2026-10-23.
- GBIF Secretariat. GBIF Backbone Taxonomy record for Hypericum perforatum L. (species 3189486). api.gbif.org. Read 2026-10-23.
- GBIF Secretariat. GBIF Backbone Taxonomy record for Crocus sativus L. (species 2747430). api.gbif.org. Read 2026-10-23.
- Ng QX et al. Systematic Reviews, 2016. A systematic review of St. John's wort for major depressive disorder. Read 2026-10-23.
- Nutritional Neuroscience, 2026. Effect of saffron on depression, anxiety and mood disorder: a GRADE assessed systematic review and meta-analysis of 34 randomized controlled trials. Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Lavender. Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Chamomile. Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Valerian. Read 2026-10-23.
- Douros A et al. International Journal of Molecular Sciences, 2016. Herb-induced liver injury in the Berlin Case-Control Surveillance Study. Read 2026-10-23.