Shellfish
3 min read
Although shellfish can be a healthy part of many people’s diets, providing significant amounts of high-quality protein, essential nutrients and healthy fats, there are some risks associated with consuming it. Because shellfish are filter-feeders — meaning they filter water through their gills to collect nutrients — water and environmental quality can affect their safety. Knowing the risks of eating shellfish and how to best avoid these potential complications will allow you to enjoy shellfish while staying healthy and safe.
Mercury and Contaminants
Almost all types of shellfish contain mercury to some extent. Consuming mercury from shellfish is not harmful to most people, but there are some populations that are more susceptible to the health risks. Young children and women who are pregnant or nursing should be especially cautious of consuming too much mercury, as it can harm the nervous system of a young child or unborn fetus. In addition to mercury, some shellfish may contain pesticides, metals or other contaminants from water. The levels of mercury and contaminants in shellfish and fish vary depending on their diet, life expectancy and habitat, but virtually all types of shellfish are safe to eat if you limit your total seafood consumption to 12 ounces per week
Foodborne Illness
Foodborne illnesses are a concern when eating shellfish and other types of seafood. A number of foodborne illnesses associated with shellfish, such as Norwalk virus, Salmonella, E. coli and hepatitis A virus, come from the contamination of water by sewage. Although foodborne illness can affect anyone who comes into contact with the contaminated food, people with certain medical conditions, such as liver disease, diabetes, altered iron metabolism, gastrointestinal issues or a suppressed immune system are at higher risk. To lower your risk of exposure, avoid consumption of raw or undercooked shellfish, purchase shellfish from reputable sources, avoid cross-contamination with other types of seafood, and store and prepare shellfish properly.
Allergy
Nearly 7 million Americans are allergic to shellfish or other seafood, according to the Food Allergy and Anaphylaxis Network. Shellfish allergies are irreversible, but approximately 60 percent of people with the allergy don’t experience a reaction until adulthood. If allergies of any type are common in your family, you are at a higher risk of developing a shellfish allergy. Allergic reactions to shellfish often start within minutes of eating the offending food and may include itching, wheezing, dizziness and swelling of the lips or mouth. In some cases, allergic reactions to shellfish can be life-threatening. The only way to ensure you avoid a reaction when you have a shellfish allergy is to avoid shellfish altogether; however, many people who are allergic to shellfish can consume fin fish.
Cholesterol and Fat
Like other animal products, shellfish contain cholesterol, but this doesn’t mean shellfish are unhealthy to eat or pose a risk to your health. In fact, other than squid and shrimp, most types of shellfish are suitable for people trying to limit the cholesterol in their diet when eaten in moderation. Furthermore, herbivorous mollusks, such as scallops and clams, contain plant sterols that can actually decrease cholesterol absorption in your intestine. Although they contain cholesterol, shellfish are good for your heart because they are generally low in saturated fat and provide healthy omega-3 fatty acids, which can help lower your risk for heart disease and high blood cholesterol.
