Health Benefits of Seafood
“Brain food,” “low fat,” “good protein,” “heart-healthy,” are all words we’ve heard to describe seafood. But there are also reports about some seafood that contains mercury, comes from polluted water, is irresponsibly produced or dangerously handled. With all of this competing information, we were left wondering, on balance, how healthy is our seafood?
Here are some simple facts based on recent research regarding the health benefits for you and your family, as well as a few areas of concern you should be aware of.
Whether you are eating fish, shellfish or for that matter, beef, chicken or pork, you need to make sure it’s fresh when you purchase it, that it’s been handled safely and prepared properly. That sounds pretty basic, but making sure your seafood has been responsibly sourced, safely handled and delivered fresh is one of the most important things you can do to make sure you get the most benefit from eating seafood.
According to a publication by Emily Oken, MD, MPH, Associate Professor, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, fish is a valuable component of the human diet. Fish is easily digestible and contains high-quality protein that provides a mix of essential amino acids that our bodies can’t make themselves.
Eating three ounces of salmon provides
1.5 grams of DHA and EPA, enough to
meet your requirements for three days.
Globally, seafood provides more protein than cattle, sheep or poultry. Fish also contain a wide variety of vitamins and minerals including vitamins A and D, phosphorus, magnesium, and selenium. Research shows that omega-3 fatty acids, found abundantly in seafood, have health benefits, such as improved infant brain development and protection against heart disease and stroke. The National Institutes of Health recommend getting 500 mg of omega-3s daily. There are several forms of these fatty acids: ALA, DHA and EPA. Of these, research suggests that DHA and EPA are the forms that protect against heart disease and stroke. ALA is abundant in plants such as flax, but the body must convert that ALA into DHA and EPA and the conversion rate is low — about 15% on average. This makes seafood a better source for your omega-3s: Eating three ounces of salmon directly provides 1.5 grams of DHA and EPA, enough to meet your requirements for three days. Three ounces of other seafoods such as oysters, sea bass and trout have enough omega-3s to meet your requirement for one day.
While you’re planning your meals to include more seafood, be mindful that some fish may be contaminated by environmental pollutants, notably methylmercury. Methylmercury is toxic to the nervous system, especially the developing brains of unborn babies, infants and young children. Coal-fired power plants are the most significant source of mercury that enters the ocean.
Because of the health risks for babies associated with methylmercury exposure, the United States Food and Drug Administration and Environmental Protection Agency recommend that women of childbearing age, pregnant women and breastfeeding mothers limit their intake of fish, and avoid all consumption of some types of fish higher in mercury (shark, swordfish, king mackerel, or tile fish).
The EPA and the FDA have concluded that the following people should eat more fish that is lower in mercury for important developmental and health benefits:
Women of childbearing age (about 16-49 years old)
Pregnant and breastfeeding women
The advice recommends that women and children eat two to three servings (8-12 ounces for adults and children over age 10, smaller amounts for younger children) of a variety of fish and shellfish each week.
All consumers can make healthy and sustainable food choices by choosing fish that is sourced sustainably and low in mercury.
If sustainable fish is not available, the EPA and the FDA have a quick reference guide to selecting fish lower in mercury.
Emily Oken, MD, MPH, Associate Professor, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute