Shellfish is a broad term for aquatic animals that have a shell or shell-like exoskeleton. Their flavors range from sweet to briny and their textures from “meaty” to soft and delicate. Many people who aren’t fish eaters will happily consume lobster, shrimp, or scallops. These shellfish are as distinct from one another as they are from fish with fins.
There are two general categories of edible shellfish: crustaceans and mollusks. Crabs, crayfish, lobster, and shrimp are all crustaceans, whose segmented bodies are covered with armor-like sections of thick or thin shell.
Mollusks include two-shelled bivalves and one-shelled univalves. Clams, oysters, mussels, and scallops are examples of bivalves. Univalves are sea creatures such as abalone, periwinkles and other snails, conch, and whelk, all which have a single shell covering a soft body. Another class of mollusks are the cephalopods, whose pliable body consists of a beaked head, an internal shell in some species, and tentacles sprouting directly from the head. Cephalopod in fact is derived from the Greek meaning “headed foot.” Squid and octopus are the most popular edible cephalopods.
Types of Shellfish
From abalone to conch to whelk, there are many more types of shellfish to try than traditional crab, lobster, shrimp.
A healthy alternative to meat, shellfish provide high-quality protein and an array of important vitamins and minerals, as well as omega-3 fatty acids. Shellfish are naturally low in calories, but how you prepare them is key to a healthy diet. For example, a 3-ounce serving of boiled or steamed shrimp has only 85 calories. An equivalent portion of breaded, deep-fried shrimp, on the other hand, packs about 240 calories, due to the oil used in frying. In the case of clams, the calories go from about 125 for steamed to 200 for fried.
Shellfish are also low in saturated fat. Some types of shellfish have moderate to high amounts of dietary cholesterol. But research now indicates that dietary cholesterol doesn’t raise your blood cholesterol levels as much as saturated fat—thus it’s less of a health risk. Many types of shellfish—crabs, scallops, mussels, clams, and lobster, among them—are actually slightly lower in cholesterol than chicken or beef.
For a full listing of nutrients, check the National Nutrient Database:
A word on shellfish and food safety
You may be aware that eating raw shellfish such as oysters and clams from contaminated waters can make you sick. But eating raw shellfish from waters that are certified clean also carries considerable heath risks. This is because the regulation of the shellfish industry is irregular at best, and agents charged with overseeing some 10 million acres of approved shellfish beds cannot carefully monitor all of them. Of course many people happily eat raw shellfish without getting sick. However, if you decide to indulge in raw seafood, make sure to buy the shellfish only from reputable markets or aquafarms. Also ask the dealer to show you the tag certifying that the shellfish were harvested from state-approved waters. If you gather your own shellfish, you should also exercise caution. Check with local authorities about the safety of any waters where you intend to harvest.
Shellfish Recipe Ideas and Cooking Tips
Shellfish are briny treats from the sea. Try these cooking tips and recipe ideas for the best shellfish.
Published April 27, 2016