DHA
Useful mainly for pregnant and breastfeeding women for fetal and infant brain development; people with elevated triglycerides.
Quick decision guide
May help most
Pregnant and breastfeeding women for fetal and infant brain development; people with elevated triglycerides
Common dosing range
200–500 mg/day for general health; 200–300 mg/day minimum in pregnancy
When to expect effects
Weeks for triglyceride reduction; months for tissue DHA saturation
Watch out for
High doses (above 3 g/day EPA+DHA combined) may increase atrial fibrillation risk and prolong bleeding time
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.
Is it worth it for you?
Use this as a quick fit check, not a diagnosis.
Worth considering if…
Probably skip if…
Evidence at a glance
| Goal | Effect | Best fit | Time |
|---|---|---|---|
visual function support Mixed Evidence | Modest reduction in dry eye symptoms and improvement in tear film stability at 1–2 g/day EPA+DHA | Adults with dry eye disease; people with low dietary fish intake and early visual complaints | Weeks to months |
visual function support
- Effect
- Modest reduction in dry eye symptoms and improvement in tear film stability at 1–2 g/day EPA+DHA
- Best fit
- Adults with dry eye disease; people with low dietary fish intake and early visual complaints
- Time
- Weeks to months
Evidence for 1 use
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
visual function support
Supplement benefitDHA is a structural component of retinal photoreceptor membranes and is important for signal transduction in vision. RCTs in dry eye disease show modest improvements in tear film stability and dry eye symptoms with omega-3 supplementation. One large NIH-funded trial (DREAM) found no benefit over placebo for dry eye, introducing uncertainty about the benefit's robustness.
Bottom line: Dry eye is the best-studied visual application; evidence is mixed but a trial is reasonable given the low risk.
Evidence is mixed
The DREAM trial (n=535) found omega-3 no better than an olive oil placebo for dry eye, conflicting with several earlier positive trials; population differences and placebo oil composition complicate interpretation.
How it works
How to take it
What to track
Safety
Know the common side effects, key cautions, and who should avoid it.
Common side effects
Serious risks
Increased atrial fibrillation risk at very high doses in some trials
Prolonged bleeding time at doses above 3 g/day EPA+DHA — relevant for surgical patients and those on anticoagulants
Who should avoid it
- People with seafood allergy should use algal oil (plant-derived, fish-free)
- People on anticoagulants or antiplatelet drugs should discuss high-dose DHA with their prescriber
- Those scheduled for surgery should discuss stopping high doses 1–2 weeks prior
Pregnancy & breastfeeding
DHA is safe and recommended in pregnancy — choose products tested for mercury and PCBs, or use algal oil which is mercury-free by nature.
Interactions
High-dose omega-3 may increase bleeding risk by modestly prolonging bleeding time; relevant above 2–3 g/day
Additive antiplatelet effect at high doses; monitor at doses above 2 g/day
DHA can modestly lower blood pressure; additive effect with antihypertensives
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 | — |
Salmon (Atlantic), 3 oz cooked
- Amount
- 0.94 g DHA
- %DV
- —
Tuna (light, canned in water), 3 oz
- Amount
- 0.17 g DHA
- %DV
- —
Mackerel (Atlantic), 3 oz cooked
- Amount
- 0.59 g DHA
- %DV
- —
Sardines (canned), 3 oz
- Amount
- 0.5 g DHA
- %DV
- —
Herring (Atlantic), 3 oz cooked
- Amount
- 0.94 g DHA
- %DV
- —
Anchovies (canned), 3 oz
- Amount
- 0.91 g DHA
- %DV
- —
Choosing a product
What to look for on the label — and what to be skeptical of.
Look for…
Be skeptical of…
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.
References by claim
Track DHA with Pilora
Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.
Coming to App StoreDisclaimer: 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.