Anxiety and stress: Evidence-Based Supplement Guide

Seven of the 72 people in Avelor with a saved stack hold something taken for anxiety or stress. This guide separates the two, because the research does. Ordinary stress and a diagnosed anxiety disorder are different problems, and **anxiety that is persistent, disabling, or getting worse is treated, not supplemented.** A clinician guideline exists specifically for the use of nutrient and plant-based products in psychiatric conditions, and it is the right frame for everything below (PMID 35311615). Ashwagandha is the compound this category runs on, and it carries the sharpest tension in any guide here. Two systematic reviews and meta-analyses reported beneficial effects on stress and anxiety, and one of them rated the certainty of that evidence as **low** for both outcomes (PMID 36017529, 39348746). A further review reported benefit for sleep (PMID 34559859). Against that, a case series from India reported ashwagandha-induced liver injury presenting as cholestatic hepatitis, progressing in some people with existing liver disease to acute-on-chronic liver failure with high mortality (PMID 37756041). A separate review examines its effects across the endocrine system, including the thyroid (PMID 38003702). So the best-selling item in this category has low-certainty benefit evidence and a documented serious harm, which is an unusual combination to find stated on a label. The rest is smaller and more honest about itself. Two systematic reviews reported that L-theanine reduced stress-related symptoms under stressful conditions, and both called for longer and larger trials before recommending it (PMID 31623400, 31758301). A green tea review reported that the cognitive effect appears under caffeine and L-theanine combined rather than either alone (PMID 28899506). Magnesium's systematic review found a suggestion of benefit in anxiety-vulnerable groups and rated the quality of the existing evidence as **poor** (PMID 28445426). A second review reached a similar position (PMID 32503201), and a post-hoc analysis reported benefit in stressed adults with low magnesium levels (PMID 33864354). Lavender has a systematic review and meta-analysis (PMID 31655395). Saffron's meta-analysis reported an effect on depressive and anxiety symptoms and **found evidence of publication bias** on its own funnel test (PMID 31135916). Omega-3's review reported an effect and likewise observed publication bias and heterogeneity (PMID 37028202). Cannabidiol has a systematic review and meta-analysis whose own authors urge caution because of limited sample sizes (PMID 38924898). The best-evidenced thing here is not a supplement. A systematic review and meta-analysis reported that aerobic exercise, resistance exercise, or a mixture of both improved symptoms of depression and anxiety (PMID 40432290). A review of interventions for generalised anxiety disorder reported growing evidence for physical exercise in its management, and placed complementary therapies including cannabinoids in the needs-further-research category (PMID 36705012). Exercise is also the only item in this guide with no interaction risk attached to it.

1. **Decide which problem you have.** Persistent or disabling anxiety is a reason to see a clinician, and the supplement evidence below is not an alternative to treatment. 2. **If you take an antidepressant or any psychiatric medicine, read the cautions before anything else.** Several items here interact with them, and one of those interactions is serious. 3. **Exercise first.** It has the best evidence in this guide and the only clean safety profile (PMID 40432290, 36705012). 4. **If you are considering ashwagandha, read its harm evidence alongside its benefit evidence** (PMID 36017529, 37756041). Both are real and both belong in the decision. 5. **Treat low-certainty findings as low-certainty.** Three of the reviews here flag poor quality or publication bias in their own results (PMID 28445426, 31135916, 37028202).

Where the research supports a timeframe, the L-theanine trial measured effects over **four weeks** (PMID 31623400), and the magnesium and vitamin B6 analysis reported a difference by **week four** (PMID 33864354). The exercise reviews pool programmes running over weeks to months (PMID 40432290). No duration is given for ashwagandha, because the trials pooled in its reviews varied and the reviews themselves call for better-designed studies before efficacy is considered established (PMID 36017529).

- **Three of these reviews flag problems in their own evidence.** Ashwagandha's certainty was rated low (PMID 36017529), magnesium's quality was rated poor (PMID 28445426), and saffron's and omega-3's analyses both detected publication bias (PMID 31135916, 37028202). Citing a positive meta-analysis while omitting its own stated limitation is the standard way this category is oversold. - **"Stress" outcomes are mostly self-reported questionnaire scores**, which is not the same as a diagnosed anxiety disorder improving. - **L-theanine's effect may not be separable from caffeine** (PMID 28899506), which matters because it is usually sold either with caffeine or as an antidote to it. - **Ashwagandha's harm evidence is a case series, not a trial** (PMID 37756041). That is a weaker design for establishing frequency and a perfectly adequate one for establishing that the harm occurs. The benefit reviews did not look for it. - **Cannabidiol product content and labelling vary**, and the anxiety evidence base is small (PMID 38924898). - **Nothing here was tested against a psychological therapy**, which is the comparison a reader weighing options would actually want.

- **St John's wort interacts with a long list of prescription medicines, and the interaction is clinically serious.** A pharmacology review sets out how these interactions work and how they might be avoided (PMID 31742659). A reference monograph covers its liver and safety profile (PMID 32491397), and an older review places it among the herb-drug interactions clinicians are warned about (PMID 10675182). If you take **any** prescription medicine, particularly an antidepressant, a contraceptive, an anticoagulant, or an immunosuppressant, do not start it without speaking to **a pharmacist or your prescriber**. - **Ashwagandha has caused liver injury.** The reported picture is cholestatic hepatitis, and in people with existing liver disease it has progressed to liver failure (PMID 37756041). Anyone with a liver condition, taking a medicine processed by the liver, or drinking heavily should raise it with **a clinician** before starting. New yellowing of the eyes or skin, dark urine, or unexplained itching means stopping and contacting **a doctor**. - **Ashwagandha also acts on the endocrine system** (PMID 38003702). Anyone with a thyroid condition or taking thyroid medication should raise it with **the clinician who manages that**. - **Kava withdrawal can be severe.** A case report describes withdrawal severe enough to warrant hospital management (PMID 40541460), and an analysis of commercial products found the active content varies considerably between them (PMID 34839465). This is a product to discuss with **a clinician** rather than to start and stop on your own. - **Do not combine 5-HTP, St John's wort, or other serotonergic products with an antidepressant** without speaking to **your prescriber** (PMID 31742659, 10675182). - **Thoughts of self-harm, panic that is escalating, or anxiety that stops you functioning are reasons to contact a clinician or an urgent service now**, not reasons to adjust a supplement.

This guide inverts the coverage pattern found in the others, and in the direction that helps. The three items here with genuine safety signals all resolve **and** carry an interaction catalogue key. Resolves and can be interaction-checked: - `avelor:sup:ashwagandha` - `avelor:sup:st-john-s-wort` - `avelor:sup:kava` - `avelor:sup:valerian` - `avelor:sup:rhodiola-rosea` - `avelor:sup:5-htp` Resolves but has no catalogue key, so it displays as recognised and is checked against nothing: - `avelor:sup:magnesium-l-threonate` - `avelor:sup:omega-3-fatty-acids` No supplement entity, and none is invented here: **L-theanine**, **lavender**, **saffron**, **cannabidiol**, **passionflower** and **GABA**. The contrast with the inflammation guide is worth recording. There, the compound with the documented liver signal could not be resolved at all. Here, the compound with the documented liver signal is `avelor:sup:ashwagandha`, it resolves, and it carries a catalogue key. Whatever process produced the supplement entity list covered the serious cases in this category and missed them in that one, which suggests the gaps are arbitrary rather than principled. The absences that remain are not trivial either. L-theanine is one of the most commonly sold calm products, and the caffeine finding means it most often arrives combined with something else. Caffeine has no supplement entity either, which is now its fourth guide.

| PMID | Title | | --- | --- | | 35311615 | "Clinician guidelines for the treatment of psychiatric disorders with nutraceuticals and phytoceuticals: The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce" | | 36017529 | "Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trials" | | 39348746 | "Effects of Ashwagandha (Withania Somnifera) on stress and anxiety: A systematic review and meta-analysis" | | 34559859 | "Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis" | | 37756041 | "Ashwagandha-induced liver injury-A case series from India and literature review" | | 38003702 | "Can Ashwagandha Benefit the Endocrine System?-A Review" | | 31623400 | "Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial" | | 31758301 | "The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review" | | 28899506 | "Green tea effects on cognition, mood and human brain function: A systematic review" | | 28445426 | "The Effects of Magnesium Supplementation on Subjective Anxiety and Stress-A Systematic Review" | | 32503201 | "The Role and the Effect of Magnesium in Mental Disorders: A Systematic Review" | | 33864354 | "Effect of magnesium and vitamin B6 supplementation on mental health and quality of life in stressed healthy adults: Post-hoc analysis of a randomised controlled trial" | | 31655395 | "Effects of lavender on anxiety: A systematic review and meta-analysis" | | 31135916 | "Effect of saffron supplementation on symptoms of depression and anxiety: a systematic review and meta-analysis" | | 37028202 | "Effects of long-chain omega-3 polyunsaturated fatty acids on reducing anxiety and/or depression in adults; A systematic review and meta-analysis of randomised controlled trials" | | 38924898 | "Therapeutic potential of cannabidiol (CBD) in anxiety disorders: A systematic review and meta-analysis" | | 40432290 | "The Effects of Aerobic and Resistance Exercise on Depression and Anxiety: Systematic Review With Meta-Analysis" | | 36705012 | "Interventions for generalized anxiety disorder" | | 31742659 | "Clinical relevance of St. John's wort drug interactions revisited" | | 32491397 | "St. John's Wort" | | 10675182 | "Herb-drug interactions" | | 40541460 | "Severe kava withdrawal managed with phenobarbital" | | 34839465 | "Characterization of Different Forms of Kava (Piper methysticum) Products by UPLC-MS/MS" |