A standard 3.5-ounce (100g) serving of canned sardines contains roughly 1 gram of combined EPA and DHA omega-3 fatty acids, split between about 0.4 grams of EPA and 0.6 grams of DHA. That single serving puts you at or near the daily omega-3 intake most health organizations recommend for heart health.
EPA and DHA Breakdown per Serving
The two omega-3s that matter most for health are EPA and DHA. EPA plays a major role in reducing inflammation throughout the body, while DHA is a structural building block of the brain and retina. Sardines deliver both in meaningful amounts.
Per 100 grams of edible fish (roughly one small can, drained):
- EPA: 0.4 grams
- DHA: 0.6 grams
- Total EPA + DHA: ~1.0 gram
These values come from canned sardines, which is how most people eat them. Fresh sardines can vary depending on the season and where they were caught, but canned sardines are remarkably consistent because the fish are packed and sealed at peak fat content. The canning process doesn’t destroy omega-3s, since these fats are stable at cooking temperatures.
How Sardines Compare to Other Fish
Sardines rank among the top omega-3 sources per serving. Wild salmon delivers slightly more (about 1.2 to 1.8 grams of combined EPA and DHA per 100g depending on the species), but sardines are cheaper, shelf-stable, and available year-round. Canned tuna, by comparison, typically provides only 0.2 to 0.3 grams of omega-3 per 100g, making sardines roughly three to four times more potent per serving.
Other fish in the same omega-3 tier as sardines include anchovies, herring, and mackerel. All of these are small, oily, cold-water fish that feed low on the food chain, which is why they concentrate healthy fats without accumulating much mercury.
Meeting the Recommended Intake
The American Heart Association recommends eating two servings of fatty fish per week, with each serving being about 3 ounces cooked. Sardines are specifically named as one of the fatty fish that counts toward this goal. Two cans of sardines per week would give you roughly 2 grams of EPA and DHA total, which aligns well with the general guidance of 250 to 500 milligrams of combined EPA and DHA per day.
If you’re eating sardines a few times a week, you likely don’t need a fish oil supplement. The omega-3s from whole fish are absorbed efficiently because they come packaged with the natural fats in the fish itself, which aids digestion and uptake.
Other Nutrients That Come Along
Omega-3 content is the headline, but sardines deliver a surprisingly complete nutritional package. A 3.5-ounce serving provides about 330 IU of vitamin D3, which covers roughly half the daily recommendation for most adults. Because sardines are eaten bones and all, they’re also one of the best non-dairy sources of calcium, typically providing 300 to 350 milligrams per can.
You also get a solid hit of protein (about 25 grams per can), vitamin B12, and selenium. Few single foods check this many nutritional boxes at once, which is part of why sardines show up so often in dietitian recommendations.
Mercury Is Essentially a Non-Issue
One reason people seek out sardines specifically is their low mercury content. FDA testing data shows sardines average just 0.013 parts per million of mercury. For perspective, swordfish averages 0.995 ppm and shark averages 0.979 ppm, making those fish roughly 75 times higher in mercury than sardines.
Sardines are so low in mercury because they’re small, short-lived fish that eat plankton. Mercury accumulates as it moves up the food chain, so large predatory fish concentrate far more of it. This makes sardines one of the safest fish for frequent consumption, including for pregnant women and young children who are typically advised to limit other seafood.
Canned vs. Fresh Sardines
Most omega-3 data, including the 1 gram per 100g figure, comes from canned sardines. If you buy fresh sardines, the omega-3 content can fluctuate based on the fish’s diet, the water temperature where it was caught, and the time of year. Cold-water sardines caught in winter tend to carry more fat. That said, the differences are generally modest, and fresh sardines remain an excellent omega-3 source.
With canned sardines, the packing medium matters slightly. Sardines packed in olive oil retain their omega-3s fully, but you’ll add extra calories from the oil. Sardines packed in water make it easier to control total fat intake while still getting the full omega-3 benefit. Some brands pack sardines in soybean oil, which adds omega-6 fats that can blunt some of the anti-inflammatory effects of the omega-3s. Water-packed or olive oil-packed are your best options.