DHA

fatty acid16,17-Epoxy-DHA

Best in the morningTake with food

What is it

DHA (docosahexaenoic acid) is a long-chain omega-3 fatty acid concentrated in the brain and retina. It is essential for neural development, vision, and overall brain function throughout life.

How it works

DHA is a major structural component of brain and retinal cell membranes — about 30 to 40 percent of the fatty acids in the brain's gray matter and over 60 percent in retinal photoreceptors are DHA. It supports membrane fluidity, neurotransmitter function, and synaptic signaling. DHA also serves as a precursor to neuroprotectins (specialized pro-resolving mediators that protect neurons and reduce inflammation). The body can convert ALA from plants into DHA, but conversion is very inefficient (typically under 1 percent), so direct intake from fish, seafood, or algal oil is the most reliable source.

Evidence for 6 uses

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Fetal brain and visual development

Grade A

Strong evidence

Maternal DHA supplementation supports fetal neurodevelopment and visual acuity. Strongly recommended during pregnancy.

Triglyceride reduction

Grade A

Strong evidence

High-dose DHA (and EPA) reduces triglycerides, with similar effect to combined EPA+DHA products.

Infant cognitive development

Grade B

Good evidence

DHA in breast milk and infant formula supports neurodevelopment. Most infant formulas now include DHA.

Visual function (general)

Grade B

Good evidence

Adequate DHA supports retinal function. Deficiency impairs visual acuity. Maintenance benefit in healthy adults less clear.

Dry eye disease

Grade C

Moderate evidence

Mixed evidence — the DREAM trial did not show benefit; some smaller trials suggested modest improvement.

Cognitive decline prevention in healthy adults

Grade D

Mixed evidence

Trials in cognitively healthy adults have not consistently shown protection against dementia.

Dosage

Most health organizations suggest at least 200 to 500 mg of DHA per day for general health. Pregnant women are often advised to take at least 200 to 300 mg of DHA daily for fetal brain development. The FDA considers up to 3 g/day of combined EPA+DHA from supplements generally safe.

When and how to take it

DHA absorbs best with a meal containing fat. Daily dosing maintains tissue DHA. Many people take DHA in the morning with breakfast to avoid bedtime burping; others take with the largest meal of the day.

Food sources

Food	Amount	%DV
Salmon (Atlantic), 3 oz cooked	0.94 g DHA	—
Tuna (light, canned in water), 3 oz	0.17 g DHA	—
Mackerel (Atlantic), 3 oz cooked	0.59 g DHA	—
Sardines (canned), 3 oz	0.5 g DHA	—
Herring (Atlantic), 3 oz cooked	0.94 g DHA	—
Anchovies (canned), 3 oz	0.91 g DHA	—

Safety

DHA is well tolerated. Side effects include occasional fishy aftertaste, burping, or mild digestive upset. High doses (above 3 g/day of EPA+DHA combined) may modestly prolong bleeding time and have been associated with increased atrial fibrillation risk at very high doses in some trials.

Who should be cautious

Pregnant and breastfeeding women benefit from DHA but should choose products tested for mercury and PCBs (or use algal oil). People with seafood allergies should use algal oil. Those on anticoagulants or scheduled for surgery should discuss high doses with their doctor.

Interactions

May increase bleeding risk at high doses with anticoagulants and antiplatelet drugs. Can lower blood pressure modestly. Combining with high-dose vitamin E may modify antioxidant effects.

Frequently asked questions

Should I take DHA-only or combined EPA+DHA?⌄

Either works for general supplementation. DHA-only products (often algal) are useful for pregnancy and brain support. Combined products are typical for cardiovascular goals.

How much DHA do pregnant women need?⌄

Most experts recommend at least 200 to 300 mg per day to support fetal brain development.

Can I get DHA from plants?⌄

ALA from flax, chia, and walnuts can be converted to DHA, but conversion is very inefficient (under 1 percent). Algal oil is the direct vegan source.

Is DHA good for the brain?⌄

It is a major structural component of the brain. Adequate intake supports normal function; whether supplementation improves cognition in well-fed healthy adults is unclear.

Is DHA safe long-term?⌄

Yes, at typical doses (200 to 1,000 mg per day). Very high doses may affect bleeding and possibly AFib in susceptible people.

Track DHA with Pilora

Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.

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Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you're pregnant, breastfeeding, on medications, or managing a chronic condition.