Sardines are packed with nutrients. But should you eat them often? - USA Today
When there is little in the fridge and no time to cook, a tiny tin of sardines can go a surprisingly long way. These fully cooked fish can turn toast, crackers, pasta or salad into a quick meal − and, because they’re shelf-stable, they’re easy to keep on hand.
Sardines also pack an impressive amount of nutrition into every bite, including protein, omega-3 fatty acids and numerous vitamins and minerals − “all at a fraction of the cost of many other seafood options,” says Laura Bellows, a registered dietitian and professor in the division of nutritional sciences at Cornell University.
But those nutrients don’t mean sardines are the right choice for everyone. Here’s why sardines can be good for you and when you may need to limit or avoid them.
Sardines are small, oily fish in the herring family, but the name does not refer to a single species. “Different countries allow different small herring-family fish to be labeled as sardines, which is why one brand may contain a different species than another,” explains Perri Halperin, a registered dietitian and clinical nutrition coordinator for the Mount Sinai Health System.
Common varieties include European, Pacific and Japanese sardines and brisling, or European sprat, but Halperin says that each of their nutritional profiles are generally similar.
Sardines feed mainly on plankton and gather in schools near the surface, allowing commercial fishermen to catch them using large nets that surround a school and close underneath like a drawstring bag.
But because sardines spoil quickly, Bellows explains, processors have to chill and clean them very soon after they are caught. The fish are then typically cooked by steaming, baking or frying before being placed in cans with water, oil, sauce or another liquid. Once sealed, the cans are heated under pressure to kill any remaining harmful microorganisms to make them shelf-stable and to soften the fish's bones to become edible.
Sardines are "often considered one of the most nutrient-dense foods you can eat because they provide several nutrients within such a small serving,” Halperin says.
Among the most important she points to are EPA and DHA − omega-3 fatty acids that "help reduce inflammation, support heart health, lower triglycerides and are important for brain and eye function." In fact, omega 3s are one of the top reasons the American Heart Association recommends two servings of fish weekly, particularly fatty varieties such as sardines.
Sardines are also an excellent source of protein, which “supports muscle maintenance and growth, tissue repair, immune function and helps keep you feeling full,” Halperin says. Even better, they provide complete protein, she adds, meaning they contain all nine essential amino acids.
And their edible bones provide "an excellent source of calcium," Bellows says, which supports bone health, muscle contraction and nerve signaling. Sardines are also among the relatively few foods that naturally contain vitamin D, she adds, which helps the body absorb that calcium.
The fish contain selenium as well, "a trace mineral that acts as an antioxidant, helping protect cells from damage," Halperin says.
And because sardines are small, short-lived and low on the food chain, Bellows notes, they accumulate much less mercury than large predatory fish. Because of this, the U.S. Food and Drug Administration classifies sardines as a “Best Choice” for children and women who are pregnant or breastfeeding.
But such advantages don't mean you can eat sardines in excess. The biggest concern is sodium, with Halperin saying that many canned products contain 300 to 500 milligrams per can, "though some varieties are even higher." While most Americans already consume more sodium than recommended, Bellows says that people with high blood pressure, heart failure or kidney disease may want to be especially careful and opt for eating fewer sardines or choosing low-sodium varieties.
Sardines are also high in purines, Halperin adds, which are substances the body breaks down into uric acid. In people with gout, excess uric acid can form crystals that cause painful joint inflammation. This is why the Arthritis Foundation includes sardines among the fish that may contribute to gout flare-ups.
Allergies are another consideration, as some 1% of Americans − roughly three million people − have a finned fish allergy, though a specific sardine allergy is a rarer subset of that group.
So long as such considerations are kept in mind, Bellows notes, "it's a healthy choice for most people to enjoy sardines regularly as part of a varied seafood diet.”
