There’s increased attention to seafood these days, often for its nutritional benefits. Besides being a good protein source, most seafood is low in fat, especially saturated fat. Fatty fish offers potential health benefits from omega-3 fatty acids; that’s partly why health experts recommend eating seafood several times a week.

With sushi bars and with seviche (a popular Mexican and Caribbean appetizer), many people have come to enjoy raw and uncooked marinated seafood. With careful control, they can be safe. Read on to learn how.

Shellfish, especially mollusks (oysters, clams, mussels, and scallops), may carry the bacterium called ‘Vibrio vulnificus’, which multiplies even during refrigeration. Other viruses in uncooked or partly cooked mollusks also can cause severe diarrhea.

High-risk individuals – those with HIV, impaired immune systems, liver and gastrointestinal disorders, kidney disease, inflammatory bowel disease, cancer, diabetes, hemochromatosis, stomach problems, or steroid dependency – should avoid eating any raw or partly cooked fish. Pregnant women, infants, young children, older adults, and those with alcohol problems also are considered at high risk. Especially during pregnancy, avoid raw fish and seafood to reduce viral and bacterial infection risks. Enjoy shellfish, canned light tuna, smaller ocean fish, or farm-raised fish, such as catfish or salmon. You can safely eat 12 ounces of these varieties of cooked fish weekly. For locally caught fish, check advisories; limit to 6 ounces if an advisory isn’t posted.

If you prepare raw fish at home, start with high-quality seafood – very, very fresh, and use it within two days. Buy from a licensed, reputable dealer. For mollusks (clams, mussels, oysters), you can ask to see the certified shipper’s tag. If you harvest your own, make sure the waters of origin are certified for safety. Even at that, eating raw fish at home isn’t advised. You’re wiser to cook fish to an internal temperature of 145 degree F to destroy parasites.

If fish is sushi-grade or high quality, sushi, sashimi, seviche, and oyster bars are generally safe. Reputable restaurants have highly trained chefs who not only know how to buy fish for safety and sanitation standards, but also know how to handle fish safely.

If you buy frozen fish such as frozen Tuna to serve as your sashimi, you need to know the qualities of frozen fish. Frozen seafood should be solidly frozen, mild in odor, and free of ice crystals and freezer burn, which is indicated by drying and discoloration. The package should not be damaged or water-stained, and it should be stored below the frost line in the store’s display freezer. These qualities apply to frozen fish and frozen prepared items such as crab cakes and breaded shrimp.

Last but not least, check for general cleanliness and quality: clean look and smell; free of insects; employees wearing disposable gloves (changed after handling nonfood and again after handling raw fish); and knowledgeable workers who can answer your questions about the freshness of the seafood. Ask when and how often fresh and flash-frozen fish come in. Be flexible; buy the freshest fish if you don’t need a specific type.