The Nutrient Database for Standard Reference published by the U.S.D.A. describes molluscan shellfish as an excellent source of vitamin B12, omega-3 fatty acids, choline, iron, selenium, and zinc. Edible molluscs consist primarily of mussels, clams, scallops, and oysters and are naturally low in carbohydrate, as well as total and saturated fat. With regard to omega-3 fatty acids, iron, selenium, and zinc, the nutrient value of some shellfish is superior to land-based protein sources, such as beef, chicken, and pork. Unfortunately, adverse human health considerations need to be noted because of naturally occurring pathogens, particularly Vibrio species, and algal toxins (brevetoxin, saxitoxin, and domoic acid) that may be present in these shellfish, as well as fecal-associated viruses (hepatitis A and norovirus) and bacteria (Salmonella) as a consequence of contamination of shellfish harvest sites. Other environmental contaminants (mercury, methylmercury, and polychlorinated biphenyls) may bioaccumulate in molluscan shellfish tissues as part of their filter feeding behavior and have potential health implications. Cooking molluscan shellfish greatly reduces the risk of foodborne infections and increases the nutrient value because of water loss; however, some vitamins are destroyed by cooking and natural toxins and environmental contaminants are not always eliminated by normal cooking temperatures. Coastal monitoring of water quality and postharvest processing of some products should help mitigate risks associated with shellfish consumption and promote a safer, nutrient-rich product.