Anxiety

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect anxiety

Grade	Level of Evidence [show legend]
	Robust research conducted with repeated double-blind clinical trials
	Multiple studies where at least two are double-blind and placebo controlled
	Single double-blind study or multiple cohort studies
	Uncontrolled or observational studies only

Level of Evidence ? The amount of high quality evidence. The more evidence, the more we can trust the results.	Outcome	Magnitude of effect ? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.	Consistency of research results ? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.	Notes
	Kava	Notable	Very High See all 8 studies	Appears to be quite reliable and effective in treating non-psychotic anxiety, with less reliability on the topic of generalized anxiety (which lavender shows some promise for). It is possible that long-term usage of kava may have similar side-effects as long term usage of benzodiazepines (note demonstrated, but wholly logical) and most studies on kava are of a few weeks in duration without any problems.
	Ashwagandha	Notable	Very High See all 3 studies	Preliminary evidence suggests potent anxiolytic effects in the context of chronic stress, with lesser potency in standard forms of anxiety not related to stress. There may be more benefit to social anxiety as well with Ashwagandha relative to other anxiolytics
	Inositol	Notable	Very High See all 4 studies	There appears to be a decrease in anxiety symptoms associated with high dose inositol, and it has been noted to be comparable to fluvoxamine in potency.
	Curcumin
	Theanine
	Lavender
	Red Clover Extract
	Bacopa monnieri
	Caffeine
	Centella asiatica
	D-Serine
	Fish Oil
	Ganoderma lucidum
	Ginkgo biloba
	Maca
	Melissa officinalis
	Nicotine
	Saffron
	Sceletium tortuosum
	Vitex agnus castus
	Yamabushitake
	Yohimbine
	Black Cohosh
	Melatonin
	N-Acetylcysteine
	Synephrine
	Valeriana officinalis
	CBD
	Holy Basil
	Phenylpiracetam

All comparative evidence is now gathered in our ​A-to-Z Supplement Reference.

The evidence for each separate supplement is still freely available ​here.

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