Most high-cholesterol foods are also high in saturated fats, which people should restrict in their diets. But we found that steamed shrimp, high in cholesterol but very low in fat, do not adversely affect the lipoprotein profile in people with normal cholesterol levels. A meal containing 150 grams, about 5 ounces, of steamed shrimp provides only 1.7 grams of fat, including 0.36 grams saturated fat, and 150 calories, compared to 150 grams of beef, which contains 14 grams of fat, including 4.7 grams of saturated fat, and 390 calories. Shrimp is second only to tuna fish as the most frequently eaten seafood in the American diet, according to the National Fisheries Institute. Yet despite this popularity, shrimp has not been previously tested for its effect on lipoproteins in such a meticulous manner, according to De Oliveira e Silva.
Lipoproteins are large molecules that transport fat and cholesterol in the body.
Lipoproteins contain combinations of cholesterol, small proteins and triglycerides, which include saturated, monounsaturated and polyunsaturated fats. The scientists suggest the findings stem from, individually or in combination, an inefficiency in absorbing shrimp cholesterol or from minor differences in the amount and kind of beneficial polyunsaturated fats, called n-3 fatty acids, in the three diets tested. In the study, the scientists tested the effects of including shrimp in a low-fat diet among 18 healthy adults who stayed at The Rockefeller University Hospital Clinical Research Center. The diets only differed in the amount of cholesterol. The baseline diet contained only 107 milligrams per day of dietary cholesterol.