Herring and sardines actually come from the same fish family and live in either freshwater or saltwater, depending on the species. These fish are among the better sources of omega-3 fats. The American Heart Association recommends that you eat fatty fish like herring and sardines at least two times each week to ensure that you get enough of these essential fats.
A 3-ounce serving of cooked Atlantic herring contains 173 calories, 20 grams of protein and 10 grams of fat, including 2.2 grams of saturated fat. The same-sized serving of canned sardines provides 177 calories, 21 grams of protein and 10 grams of fat, including only 1.3 grams of saturated fat. A serving of either fish contains more than the recommended 500 milligrams per day of omega-3 fats, with a serving of Atlantic herring providing 1,712 milligrams and a serving of sardines providing 835. Omega-3 fats may help lower your risk for high blood pressure, high triglycerides and heart disease.
Both of these fish are good sources of vitamins, although herring is a better source of vitamins overall. A serving of herring provides 15 percent of the daily value for riboflavin and vitamin B-6, 18 percent of the DV for niacin, 186 percent of the DV for vitamin B-12 and 46 percent of the DV for vitamin D. Eating a serving of sardines gives you 11 percent of the DV for riboflavin, 22 percent of the DV for niacin, 7 percent of the DV for vitamin B-6, 127 percent of the DV for vitamin B-12 and 41 percent of the DV for vitamin D. The B vitamins are important for keeping your skin and hair healthy and for turning the food you eat into energy, while vitamin D helps keep your bones strong and your immune system working properly.
Each serving of herring provides 26 percent of the DV for phosphorus and 10 percent of the DV for potassium as well as smaller amounts of the other essential minerals. However, canned sardines are a better source of minerals, providing 33 percent of the DV for calcium, 14 percent of the DV for iron, 42 percent of the DV for phosphorus and 10 percent of the DV for potassium. Unfortunately, a serving of canned sardines also contains 430 milligrams of sodium, or 18 percent of your DV. Calcium helps keep your bones strong, iron is important for forming red blood cells to carry oxygen throughout your body, phosphorus forms the compound your body uses to store energy and potassium counteracts the effects of sodium, helping you maintain normal blood pressure levels.
While both of these fish are low in saturated fat and filled with essential nutrients, you still don't want to go overboard and eat them in large amounts. Although they are among the fish lowest in mercury, they can still contain some of this and other contaminants, so you shouldn't eat more than 12 ounces of these or other fish each week. Try adding chopped herring, dill and mustard to potato salad or try adding sardines, lemon juice and garlic to whole-wheat pasta and sauce.
- USDA Nutrient Data Laboratory: Fish, Herring, Atlantic, Cooked, Dry Heat
- USDA Nutrient Data Laboratory: Fish, Sardine, Atlantic, Canned in Oil, Drained Solids With Bone
- Nutrition Reviews: Balancing the Benefits of n-3 Polyunsaturated Fatty Acids and the Risks of Methylmercury Exposure From Fish Consumption
- American Pregnancy Association: Mercury Levels in Fish
- Colorado State University Extension: Omega-3 Fatty Acids
- American Heart Association: Fish 101
- The Oxford Encyclopedia of Food and Drink in America; Andrew F. Smith, editor in chief
- U.S. Food and Drug Administration: 14. Appendix F: Calculate the Percent Daily Value for the Appropriate Nutrients
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