DHA is found primarily in fatty fish, shellfish, and algae. Smaller amounts show up in eggs, organ meats, and certain fortified foods. If you eat fish two or three times a week, you’re likely getting a meaningful amount, but the specific fish you choose matters a lot.
Fatty Fish: The Richest Source
Cold-water fatty fish deliver more DHA per serving than any other whole food. Herring leads the pack at roughly 935 mg of DHA per 100 grams (about 3.5 ounces), followed by sardines at around 535 mg and trout at approximately 225 mg per 100 grams. Salmon, mackerel, and anchovies are also top-tier sources, consistently ranked among the highest in omega-3 content by nutrition databases.
The good news is that the fish highest in DHA also tend to be low in mercury. Salmon (fresh or canned), sardines, herring, trout, anchovies, and canned mackerel all fall into the low-mercury category according to California’s Office of Environmental Health Hazard Assessment. That means you can eat them several times a week without concern. The fish to limit or avoid for mercury reasons, like swordfish, shark, king mackerel, and bluefin tuna, are a separate group entirely.
Canned options count. Canned salmon, sardines, and light tuna are affordable, shelf-stable, and still deliver substantial DHA. If fresh fish isn’t practical for your budget or schedule, canned versions are a solid workaround.
Shellfish and Other Seafood
Shellfish aren’t as concentrated in DHA as fatty fish, but they still contribute meaningful amounts. Oysters, mussels, crab, and shrimp all contain DHA, and they’re low in mercury. Squid (calamari) is another underappreciated source. If you eat a mix of seafood throughout the week, including shellfish alongside fish, you’ll build up your DHA intake without relying on the same few meals.
Eggs and Meat
Eggs contain DHA in the yolk, though the amount depends heavily on how the hens were raised. Pasture-raised eggs have roughly twice the DHA of eggs from caged hens. The total per egg is still modest compared to a serving of fish, but eggs are eaten so frequently that they add up over a week. Some brands sell “omega-3 eggs” from hens fed flaxseed or algae, which pushes the DHA content higher. Check the label for a specific milligram claim if you want to compare brands.
Most cuts of beef, chicken, and pork contain very little DHA. The exception is organ meat from grass-fed animals. Grass-fed beef liver, for instance, provides about 83 mg of DHA per 100 grams, along with notable amounts of EPA. That’s a fraction of what fish provides, but it’s significantly more than you’d get from a steak or chicken breast. If you already eat liver occasionally, it’s a useful bonus source.
Algal Oil: The Plant-Based Option
DHA in the ocean food chain originates from microalgae, not from the fish themselves. Fish accumulate DHA by eating algae or smaller organisms that ate algae. This is why algal oil, extracted directly from microalgae like Schizochytrium, is the most concentrated plant-based DHA source available. A single algal oil capsule typically delivers around 400 to 500 mg of DHA, comparable to a serving of fatty fish.
Algal oil is the go-to for vegetarians, vegans, and anyone who doesn’t eat fish. It’s also worth knowing that the DHA in algal oil is bioavailable in the same way fish oil DHA is. Studies comparing the two have confirmed that the body absorbs and uses them similarly. Most infant formulas sold in the United States have included algae-derived DHA since 2002, which speaks to how well-established this source is.
Why Flax and Chia Don’t Replace Fish
Flaxseed, chia seeds, walnuts, and hemp seeds are often promoted as omega-3 foods, and they are, but they contain ALA, a shorter omega-3 fat that your body must convert into DHA before it can use it the same way. That conversion is remarkably inefficient. In men, only about 0% to 4% of dietary ALA becomes DHA. Women convert somewhat more, around 9%, likely due to the influence of estrogen. Research from Oregon State University’s Linus Pauling Institute confirmed these figures.
In practical terms, this means even a generous daily intake of flaxseed oil won’t reliably raise your DHA levels. These foods are healthy for other reasons, and ALA itself has benefits, but they aren’t a dependable DHA source. If you don’t eat fish, algal oil supplements are a far more efficient path to adequate DHA.
Fortified Foods
Food manufacturers add DHA to a growing list of products: certain brands of milk, yogurt, juice, soy beverages, and eggs. The amounts per serving are typically small, often 32 to 50 mg, so they’re best seen as a supplement to your diet rather than a primary source. You’d need to check individual product labels, since DHA content varies widely between brands and there’s no standard fortification level. Still, if you drink fortified milk daily or eat fortified yogurt regularly, those small doses accumulate.
How Much DHA You Actually Need
There’s no single official daily requirement for DHA alone, but the general guidance points to at least 250 to 500 mg per day of combined DHA and EPA for general health. The FDA considers up to 3 grams per day from food and supplements to be safe.
During pregnancy, the bar is higher. The FDA advises at least 200 mg of DHA daily for pregnant women, but a 2024 expert review recommended that pregnant individuals with low DHA intake aim for 600 to 1,000 mg per day of DHA and EPA. DHA is critical for fetal brain and eye development, and the third trimester is when demand peaks.
For context, a single 3.5-ounce serving of herring or sardines gets you to or past the 500 mg mark in one meal. Two servings of fatty fish per week will cover most people’s needs comfortably. If fish isn’t part of your diet, one algal oil capsule daily achieves a similar result.
Practical Tips for Getting More DHA
- Canned sardines or salmon on toast or in salads are one of the easiest, cheapest ways to hit your weekly target.
- Frozen fish fillets (salmon, trout, herring) are often less expensive than fresh and retain their DHA content through freezing.
- Algal oil capsules are the simplest option if you eat no seafood at all, delivering 400+ mg of DHA per capsule.
- Pasture-raised or omega-3 enriched eggs add a small daily boost, especially if fish is only an occasional meal for you.
- Fortified foods can fill small gaps but shouldn’t be your only strategy.