Best Supplements for Anxiety: 7 Evidence-Backed Options

From magnesium glycinate to ashwagandha and L-theanine, here are the supplements with the strongest clinical evidence for daily anxiety relief.

Anxiety affects roughly 19% of adults in any given year, and a large fraction of those people prefer to manage it without prescription medication. While supplements are not a substitute for therapy or medical care for diagnosed disorders, several have strong clinical evidence for reducing the daily background level of stress and anxiety. Here are the seven most-studied, ranked by quality of evidence.

1. Ashwagandha (KSM-66), 600 mg/day

Ashwagandha is the most-studied adaptogen for stress. Multiple placebo-controlled trials show meaningful reductions in perceived stress, cortisol, and anxiety symptoms within 4-8 weeks. The KSM-66 extract (root only, 5% withanolides) is the standardised form used in nearly all positive trials. Avoid if pregnant, on thyroid medication, or with autoimmune conditions.

2. Magnesium Glycinate, 200-400 mg elemental

An estimated 50% of adults are magnesium deficient, and the symptoms, muscle tension, sleep difficulty, irritability, overlap with anxiety. Glycinate is the gentlest form on the stomach and most calming (the glycine portion has GABA-like activity). Take 200-400 mg of elemental magnesium in the evening.

3. L-Theanine, 200 mg

L-theanine, an amino acid almost exclusive to tea leaves, promotes alpha brain waves, the EEG pattern of calm, focused alertness. The Suntheanine form (pure L-isomer) is what clinical trials use. It works within 30-60 minutes and pairs well with caffeine to smooth the stimulant edge. Take 100-400 mg as needed.

4. Saffron Extract (Affron), 28 mg/day

Saffron has surprisingly robust clinical evidence for mood and anxiety, multiple trials have shown it performs comparably to standard mood interventions at the 28-30 mg daily dose. The Affron and Satiereal branded extracts are the most-studied. Effects typically emerge over 4-6 weeks.

5. Inositol (Myo + D-Chiro 40:1), 2-4 g/day

At higher doses (12-18 g), inositol has been studied for panic disorder and OCD. At more reasonable doses (2-4 g), it can support a calmer baseline, especially in women dealing with anxiety related to hormonal fluctuations or PCOS.

6. Holy Basil (Tulsi), 500 mg/day

A gentler adaptogen than ashwagandha. Tulsi has thousands of years of use in Ayurveda and modern research suggests modest cortisol-lowering and immune-balancing effects. A good choice for daily use during high-stress periods.

7. Phosphatidylserine, 100-300 mg/day

PS is a phospholipid concentrated in brain cell membranes. It blunts the cortisol response to mental and physical stressors, particularly useful for high-performers or athletes dealing with overtraining-related anxiety.

Putting it together

If you're starting from scratch, the highest-leverage combination is: magnesium glycinate in the evening + ashwagandha morning and evening + L-theanine as needed for acute moments. Add saffron if mood is also low. Allow 4-6 weeks to evaluate. None of these supplements should replace professional support for diagnosed anxiety disorders.

Supplements work best as one part of a broader strategy that includes sleep, movement, sunlight, and connection.

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