Higher levels of sodium and cholesterol in some “fish without fins” raise special health concerns for older men.

Advice about healthy nutrition always seems to end with the refrain “and try to eat fish twice a week.” But taste preferences, cost, and proper preparation present barriers. “If you like fish and you enjoy it, trying to get it once or twice a week is a good thing, but it may not be feasible,” says Dr. Helen Delichatsios, an assistant professor of medicine at Harvard Medical School.

Many men also enjoy eating the other tasty sea creatures lurking among the salmon, tuna, and snapper. The most commonly consumed include lobster, shrimp, crab, scallops, mussels, clams, squid (calamari), and octopus. These “fish without fins” have a place on a healthy plate, but they may clash with some health concerns of older men. “Think of these as occasional luxury foods,” Dr. Delichatsios says.

Barriers to eating fish

The American Heart Association and other experts advise everyone to eat fish twice a week to obtain lean protein and heart-healthy omega-3 fatty acids. Types of fish with abundant omega-3s include Atlantic salmon, mackerel, lake trout, herring, bluefish, and tuna.

But some people have trouble following the prescription.

Good-quality fish, especially fresh fish, is expensive. And you have to know how to cook it so that anybody would actually want to eat it. “Someone may not know how to prepare it, except for tuna fish in a can,” Dr. Delichatsios says.

Breading and frying in oil makes fish tasty to many people, but packs the dish with fat and salt. For many, the solution is to order fish when dining in restaurants. Fish that are grilled or pan seared with minimal oil or butter are healthy choices.

Seafood without fins

For those who don’t particularly care for fish, shellfish and other alternatives may also deliver lean protein and nutrients, but they are expensive and some raise a few health concerns for men.

Cholesterol and sodium: Shrimp are high in cholesterol and sodium; crab, lobster, and octopus are high in sodium. Battered and deep-fried shellfish and squid (calamari) top the charts in both cholesterol and sodium, which raise the risk for high blood pressure and heart disease (see table).

Potassium: Seafood is rich in potassium, which tends to counterbalance the effects of sodium. However, men with chronic kidney disease cannot excrete potassium as effectively, so must limit the intake of this nutrient.

Gout: Meat, poultry, and seafood contain substances called purines, which can trigger gout attacks.

Nutrients vs. food

This is all sound advice, but in reality people don’t eat potassium and sodium—they eat food. Shrimp may be high in cholesterol compared with a chunk of salmon, but a handful of shrimp tossed into a stir-fry can be a powerful incentive to following mother’s advice and eating all your vegetables.

As for breaded and fried clams, calamari, and crab cakes—tuck in and enjoy now and then. But reserve the twice-a-week seat at your table for salmon, tuna, and flounder.