Short answer: Diet may help anxiety a little, but the evidence is preliminary. Omega-3 supplement studies found less anxiety, while a meta-analysis of whole-diet trials found no effect. The most practical steps are eating regular meals with protein, cutting back on caffeine, and reconsidering alcohol, which brings rebound anxiety.

Diet is not a substitute for the treatment your doctor prescribes. Do not stop or change any medication on the basis of anything here. Stopping some anti-anxiety medicines, such as benzodiazepines, suddenly can be dangerous. Discuss any change with your doctor or care team.

No diet has been shown to treat anxiety disorders, but some food habits may make anxiety easier or harder to manage. The evidence is preliminary. A few omega-3 supplement trials found less anxiety. Trials of improving the whole diet found no effect on anxiety, though they did help depression a little. What you can act on today: eat regularly, watch caffeine and limit alcohol.

What to eat and avoid for anxiety

Start here

  1. Eat regular meals. Include protein, healthy fat and slow carbohydrates every time, and don’t skip breakfast. Low blood sugar produces symptoms that overlap with anxiety.
  2. Check your caffeine. If you have more than 200 mg a day (roughly two cups of coffee) and feel anxious, try cutting back for two weeks. Green tea is a gentler swap.
  3. Reconsider alcohol. Its short-term calm is followed by rebound anxiety. A two-to-four-week break can show whether it is contributing.
  4. Eat fatty fish two to three times a week. Salmon, sardines, mackerel and anchovies supply EPA and DHA. The supplement trials that found less anxiety used at least 2 grams a day; discuss any supplement with your doctor or pharmacist first (see Safety below).
  5. Get magnesium from food. Pumpkin seeds, leafy greens, almonds, dark chocolate and black beans. Many people in Western countries fall below the recommended intake.
  6. Add fermented foods. Yogurt, kefir, sauerkraut, kimchi or miso, one to three servings a day.
  7. Use a Mediterranean-style pattern as the base. It is linked to lower depression risk; its effect on anxiety is less studied.

Foods that may calm

  • Fatty fish: salmon, mackerel, sardines, anchovies and herring provide the omega-3s studied in the anxiety trials. Two to three servings a week fits the observational evidence; the supplement trials used higher doses (2-2.5 grams a day of EPA plus DHA). See is salmon good for your brain?
  • Magnesium-rich foods: leafy greens (spinach, Swiss chard, kale), pumpkin seeds, almonds, cashews, black beans, dark chocolate and avocado.
  • Fermented foods: live yogurt, kefir, sauerkraut, kimchi, miso, tempeh and kombucha support gut bacteria. Vary them, as each delivers different microbes. See fermented foods.
  • Slow carbohydrates and fiber: oats, brown rice, quinoa, lentils, chickpeas, sweet potatoes and squash release glucose slowly and feed gut bacteria. Carbohydrates also trigger insulin, which clears competing amino acids from the blood so more tryptophan, the building block of serotonin, reaches the brain.
  • B vitamins: B6 is needed to make GABA, and B12 and folate for brain chemistry generally. Low thiamine (B1) has been associated with anxiety. Sources include poultry, fish, eggs, legumes, leafy greens, whole grains and liver.
  • Green tea: contains L-theanine and modest caffeine (25-50 mg per cup, compared to 80-200 mg in coffee). See is green tea good for your brain?

The evidence: what studies show

Whole diets: no clear effect on anxiety

A 2019 meta-analysis of randomized trials (Firth 2019) found that diet changes reduced depressive symptoms slightly but had no significant effect on anxiety symptoms (11 trials, 2,270 participants). Lassale 2019, which pooled 41 observational studies, found a 33 percent lower risk of depression with the highest Mediterranean diet adherence, but it covered depression only, not anxiety. For more on the depression evidence, see diet and depression.

A calming effect of the Mediterranean diet is plausible, given its omega-3s, magnesium, B vitamins, polyphenols and fiber, but it has not been shown in trials.

Omega-3s: some benefit in supplement trials

In a double-blind trial (Kiecolt-Glaser 2011), 68 medical students took 2.5 grams a day of omega-3s (mostly EPA) or placebo for 12 weeks around exams. The omega-3 group had a 20 percent reduction in anxiety symptoms compared with placebo. Their stimulated production of IL-6, an inflammatory signal, fell by 14 percent, and depressive symptoms didn’t change. The students did not have an anxiety disorder.

Su 2018 pooled 19 clinical trials (some without a placebo group) with 2,240 participants. Omega-3 treatment was associated with a small-to-moderate reduction in anxiety compared with controls. The effect was greater in people with a clinical diagnosis, and was significant only in studies using at least 2 grams a day. The authors called for better trials in people whose main problem is anxiety.

Magnesium: mixed, low-quality evidence

A systematic review of 18 studies in anxiety-prone people (Boyle 2017) found that about half reported a benefit: 4 of 8 in mildly anxious people, 4 of 7 in premenstrual syndrome and 1 of 2 in high blood pressure. There was no effect on postpartum anxiety. The authors concluded that the evidence suggests a benefit but that its quality is poor. Results like these are why this page carries an overall evidence grade of “Preliminary”.

An open-label trial (Tarleton 2017) enrolled 126 adults with mild-to-moderate depression. Taking 248 mg of elemental magnesium a day for six weeks improved both depression and anxiety scores, with effects within two weeks. Anxiety was a secondary outcome, and there was no placebo, so expectation effects can’t be ruled out.

Fermented foods: early hints only

In a small trial (Tillisch 2013), 12 healthy women ate a fermented milk product with live bacteria for four weeks. Compared with women who had a non-fermented dairy product (11) or nothing (13), they showed reduced responses in brain areas involved in emotion during a task with emotional faces. The study measured brain activity, not anxiety, and the women had no psychiatric symptoms.

A survey of 710 young adults (Hilimire 2015) looked at people high in neuroticism (a tendency to worry). Those who ate fermented foods more often had fewer social anxiety symptoms, after allowing for healthy eating and exercise. The study was cross-sectional, so it cannot show whether fermented foods reduce anxiety. More on this in our gut-brain axis diet guide.

L-theanine: small studies

L-theanine is an amino acid found almost only in tea. A study gave 35 healthy young adults 50 mg of L-theanine or placebo (Nobre 2008). L-theanine increased alpha brain waves, a pattern linked with relaxed alertness, over the 45 to 105 minutes after it was taken. Evidence in people is limited to small trials like this. Animal studies suggest it reaches the brain and affects GABA, serotonin and dopamine. The mix of L-theanine and modest caffeine in green tea appears to produce calm focus rather than coffee’s jitters.

What makes anxiety worse

Caffeine

Caffeine blocks adenosine (a chemical that builds sleep pressure), raises norepinephrine and dopamine, and stimulates the stress-hormone system. Its effect on anxiety depends on dose and person. People who break down caffeine slowly, because of variation in the CYP1A2 gene, feel longer and stronger effects from the same dose.

A review (Smith 2002) concluded that moderate caffeine has largely positive effects for most people. But large amounts, or caffeine in sensitive groups such as people with anxiety disorders, can increase anxiety. For healthy adults, up to about 400 mg of caffeine a day is generally considered safe (200 mg in pregnancy). Not everyone with anxiety needs to give it up, but anyone with unexplained or worsening anxiety should try cutting back. Coming off caffeine can briefly worsen symptoms at first.

Alcohol

In the short term, alcohol boosts GABA, the brain’s main calming messenger, and dampens glutamate, its main excitatory one. That is why many people with anxiety drink to relax. As blood alcohol falls, the effect rebounds. GABA activity drops below baseline, glutamate surges, and the nervous system becomes overexcited. This “hangxiety” can be worse than the anxiety before drinking and can last into the next day.

Regular drinking depletes magnesium, disrupts B vitamins and sleep, and dulls GABA receptors, so the brain responds less to its own calming signals. A review (Kushner 2000) concluded that anxiety disorders and alcohol problems can each lead to the other. Short-term relief from drinking, plus longer-term anxiety from drinking and withdrawal, can create a cycle of rising anxiety and alcohol use.

Sugar spikes and skipped meals

When blood glucose drops fast, the body releases adrenaline and cortisol to raise it. These hormones cause a racing heart, tremor, sweating and a sense of danger, almost identical to the symptoms of a panic attack. In someone prone to anxiety, the brain can read these signals as a threat. A cycle can follow: anxiety suppresses appetite, meals get skipped, quick sugary food fills the gap, blood sugar crashes, and the crash feels like worsening anxiety. Our article on blood sugar and brain function explains the mechanism.

The Women’s Health Initiative analysis (Gangwisch 2015) followed about 70,000 postmenopausal women. Those in the highest fifth of dietary glycemic index had 22 percent higher odds of developing depression over three years than those in the lowest fifth. This study measured depression, not anxiety, and is observational. Regular meals with protein, fat and fiber are simple and cheap, though their effect on anxiety has not been tested in trials.

Why diet might affect anxiety

These are proposed pathways, mostly from lab and observational studies.

GABA. GABA is the brain’s main “brake”. Benzodiazepines, the most widely prescribed class of anti-anxiety drugs, work by enhancing GABA receptor activity. The brain needs vitamin B6 to make GABA. Magnesium is thought to affect GABA signaling, though whether that has a calming effect in people is not established.

Stress hormones. In anxiety disorders, the stress-hormone (HPA) system is often dysregulated, with cortisol that stays high or doesn’t switch off properly. Blood sugar crashes trigger cortisol. A small study (Delarue 2003) gave seven healthy men high-dose fish oil (7.2 g a day) for three weeks. It blunted the rise in cortisol and adrenaline during a mental stress test.

Inflammation. A meta-analysis of 14 studies (Costello 2019) found that CRP, an inflammation marker, was modestly higher in people with generalized anxiety disorder than in controls. The authors called the evidence preliminary. Whether an inflammatory diet increases anxiety through this route has not been shown in trials.

Safety

  • Supplements (including omega-3, magnesium and L-theanine) can interact with medicines. Ask a doctor or pharmacist before starting one, especially if you are pregnant, breastfeeding, taking medication or have a health condition.
  • Fish oil and omega-3 supplements can increase bleeding risk with anticoagulant or antiplatelet drugs. In trials, doses above about 1 g a day were linked to a higher risk of atrial fibrillation.
  • Magnesium: the upper limit from supplements is 350 mg a day for adults; higher doses can cause diarrhea. Take extra care with kidney disease or if you take medications that interact with magnesium.
  • Caffeine: up to about 400 mg a day is the usual upper intake for healthy adults, and 200 mg a day in pregnancy.
  • Medication: if you have an anxiety disorder, keep working with your doctor, psychiatrist or psychologist. Do not stop or reduce a medication without your doctor.

Frequently asked questions

Do I need a magnesium supplement, or is food enough?

Most people can meet their needs from leafy greens, nuts, seeds, legumes and whole grains eaten regularly, though many fall short. If you think your intake is low, talk to a healthcare provider before taking a supplement.

Should I cut out all sugar?

No. Whole fruit has natural sugar plus fiber that slows absorption. Keep added sugar below 25 grams a day, avoid sugary drinks, and eat carbohydrates as part of a meal rather than alone.

Sources

  • Boyle, N. B., Lawton, C., & Dye, L. (2017). The effects of magnesium supplementation on subjective anxiety and stress — a systematic review. Nutrients, 9(5), 429. doi:10.3390/nu9050429
  • Costello, H., Gould, R. L., Abrol, E., & Howard, R. (2019). Systematic review and meta-analysis of the association between peripheral inflammatory cytokines and generalised anxiety disorder. BMJ Open, 9(7), e027925. doi:10.1136/bmjopen-2018-027925
  • Delarue, J., Matzinger, O., Binnert, C., Schneiter, P., Chiolero, R., & Tappy, L. (2003). Fish oil prevents the adrenal activation elicited by mental stress in healthy men. Diabetes & Metabolism, 29(3), 289-295. doi:10.1016/s1262-3636(07)70039-3
  • Firth, J., Marx, W., Dash, S., et al. (2019). The effects of dietary improvement on symptoms of depression and anxiety: A meta-analysis of randomized controlled trials. Psychosomatic Medicine, 81(3), 265-280. doi:10.1097/PSY.0000000000000673
  • Gangwisch, J. E., Hale, L., Garcia, L., et al. (2015). High glycemic index diet as a risk factor for depression: analyses from the Women’s Health Initiative. American Journal of Clinical Nutrition, 102(2), 454-463. doi:10.3945/ajcn.114.103846
  • Hilimire, M. R., DeVylder, J. E., & Forestell, C. A. (2015). Fermented foods, neuroticism, and social anxiety: an interaction model. Psychiatry Research, 228(2), 203-208. doi:10.1016/j.psychres.2015.04.023
  • Kiecolt-Glaser, J. K., Belury, M. A., Andridge, R., Malarkey, W. B., & Glaser, R. (2011). Omega-3 supplementation lowers inflammation and anxiety in medical students: a randomized controlled trial. Brain, Behavior, and Immunity, 25(8), 1725-1734. doi:10.1016/j.bbi.2011.07.229
  • Kushner, M. G., Abrams, K., & Borchardt, C. (2000). The relationship between anxiety disorders and alcohol use disorders: a review of major perspectives and findings. Clinical Psychology Review, 20(2), 149-171. doi:10.1016/s0272-7358(99)00027-6
  • Lassale, C., Batty, G. D., Baghdadli, A., et al. (2019). Healthy dietary indices and risk of depressive outcomes: a systematic review and meta-analysis of observational studies. Molecular Psychiatry, 24(7), 965-986. doi:10.1038/s41380-018-0237-8
  • Nobre, A. C., Rao, A., & Owen, G. N. (2008). L-theanine, a natural constituent in tea, and its effect on mental state. Asia Pacific Journal of Clinical Nutrition, 17(S1), 167-168. PMID:18296328
  • Smith, A. (2002). Effects of caffeine on human behavior. Food and Chemical Toxicology, 40(9), 1243-1255. doi:10.1016/s0278-6915(02)00096-0
  • Su, K. P., Tseng, P. T., Lin, P. Y., et al. (2018). Association of use of omega-3 polyunsaturated fatty acids with changes in severity of anxiety symptoms: a systematic review and meta-analysis. JAMA Network Open, 1(5), e182327. doi:10.1001/jamanetworkopen.2018.2327
  • Tarleton, E. K., Littenberg, B., MacLean, C. D., Kennedy, A. G., & Daley, C. (2017). Role of magnesium supplementation in the treatment of depression: a randomized clinical trial. PLOS ONE, 12(6), e0180067. doi:10.1371/journal.pone.0180067
  • Tillisch, K., Labus, J., Kilpatrick, L., et al. (2013). Consumption of fermented milk product with probiotic modulates brain activity. Gastroenterology, 144(7), 1394-1401.e4. doi:10.1053/j.gastro.2013.02.043