Years ago, shrimp was considered to be taboo for people who have heart disease or are watching their cholesterol numbers. That’s because a small serving of 3.5 ounces supplies about 200 milligrams (mg) of cholesterol. For people at high risk for heart disease, that amounts to a full day’s allotment. For everyone else, 300 mg is the limit.
However, shrimp is very low in total fat, with about 1.5 grams (g) per serving and almost no saturated fat at all. Saturated fat is known to be particularly harmful to the heart and blood vessels, in part because our bodies can efficiently convert it to low-density lipoprotein (LDL), otherwise known as “bad” cholesterol. But an LDL level is only part of what influences your heart disease risk. Read more about the causes and risks of heart disease.
What the research says
Since my patients often ask me about shrimp and cholesterol, I decided to review the medical literature and discovered a fascinating study from Rockefeller University. In 1996, Dr. Elizabeth De Oliveira e Silva and colleagues put a shrimp-based diet to the test. Eighteen men and women were fed about 10 ounces of shrimp — supplying nearly 600 mg of cholesterol — every day for three weeks. On a rotating schedule, the subjects were also fed a two-eggs-per-day diet, furnishing about the same amount of cholesterol, for three weeks. They were fed a baseline low-cholesterol diet for another three weeks.
After the three weeks were up, the shrimp diet did in fact raise LDL cholesterol by about 7 percent compared to the low-cholesterol diet. However, it also increased HDL, or “good” cholesterol, by 12 percent and lowered triglycerides by 13 percent. This reveals that shrimp had a total positive effect on cholesterol because it improved both HDL and triglycerides a total of 25 percent with a net improvement of 18 percent.
A suggests that low HDL levels are associated with total inflammation in relation to heart disease. Therefore, a higher HDL is desirable.
The egg diet came out looking a worse, bumping up LDL by 10 percent while raising HDL only about 8 percent.
The bottom line
The bottom line? Heart disease risk is based upon more than just LDL levels or total cholesterol. Inflammation is a major player in heart disease risk. Because of shrimp’s HDL benefits, you can enjoy it as part of a heart-smart diet.
Perhaps just as important, find out where your shrimp comes from. Much of the shrimp now sold in the United States comes from Asia. In Asia, farming practices, including the use of pesticides and antibiotics, have been environmentally devastating and may have detrimental effects on human health. Read more about shrimp farming practices in Asia on National Geographic’s website, in an article initially posted in 2004.