Postmenopausal women who frequently eat baked or broiled fish have a lower risk of developing heart failure than those who eat more fried fish, according to a study reported in Circulation: Heart Failure, an American Heart Association journal. Coronary heart disease is the single leading cause of death in women.
In a large-scale analysis of dietary data from 84,493 postmenopausal women in the Women’s Health Initiative Observational Study, women who ate the most baked or broiled fish (five or more servings per week) had a 30 percent lower risk of heart failure compared to women who seldom ate it (less than one serving per month).
Prior research had found that omega-3 fatty acids in fish lower the risk of cardiovascular disease by decreasing inflammation, resisting oxidative stress and improving blood pressure, cardiac and blood vessel function.
What is new in this study is that it shows that both the type of fish and the cooking method may affect heart failure risk. The researchers found that dark fish (salmon, mackerel and bluefish) which are higher in fat were associated with a significantly greater risk reduction than either tuna or white fish (sole, snapper and cod).
In a similar analysis, eating fried fish was associated with increased heart failure risk. Even one serving a week of fried fish was associated with a 48 percent higher heart failure risk.
In addition, this study focused on heart failure rather than general cardiovascular disease. While previous studies have linked omega-3 fatty acids to a decrease in some types of heart disease, their precise relationship to heart failure risk was unclear. Researchers sought to clarify the connection between fish and heart failure risk in postmenopausal women.
According to the researchers, heart failure affects about 5.7 million people in the United States. Although the heart continues to function in this disease, it’s unable to pump blood efficiently enough to meet the body’s needs. Heart failure has many different causes, including smoking, high blood pressure, diabetes, overweight, lack of physical activity and poor diet. It’s often treatable with lifestyle changes, medicine or surgery.
“Not all fish are equal, and how you prepare it really matters,” said Donald Lloyd-Jones, M.D., Sc.M., senior author of the study. “When you fry fish, you not only lose a lot of the benefits, you likely add some things related to the cooking process that are harmful.”
Other research has shown that frying increases the trans fatty acid (TFA) content of foods, which is associated with increasing risk for heart disease.