The study comes on the heels of an exhaustive review, published last month in the American Journal of Clinical Nutrition, that challenged the conventional wisdom on the dangers of saturated fat.
Despite the fat’s apparent ill effects on arteries, studies over the years have failed to consistently show a link between saturated fat and heart disease, and the review put an exclamation point on those inconclusive results. After analyzing 21 studies that included nearly 350,000 people, the authors found “no significant evidence” that eating more saturated fat increases a person’s risk of heart disease or stroke.
Ronald M. Krauss, MD, of the Children’s Hospital Oakland Research Institute, in Oakland, Calif., and the other authors of that study noted that the longstanding emphasis on cutting saturated fat intake ignores the possibility that some people replace those calories by eating more refined carbohydrates, which can boost cholesterol and contribute to heart disease in their own right. On the other hand, people who replace saturated fat with polyunsaturated fats may indeed improve their heart health, the researchers suggested.
Dr. Mozaffarian and his colleagues appear to have confirmed that hypothesis, says Dr. Krauss. “We should be thinking more about being more generous in our allotment of polyunsaturated fats,” he says.
The Institute of Medicine, an independent organization that advises the U.S. government on health matters, recommends that people consume no more than 10% of their calories from polyunsaturated fat. The average intake in the U.S. is even less, around 6% to 7% of total calories, according to Dr. Mozaffarian. The recommended limits on polyunsaturated fat intake are based on relatively shaky evidence, he adds, and should be revised.
“I agree strongly with the notion that rather than focusing on further reductions in saturated fat per se…we should be thinking much more seriously about finding ways of increasing our intake of polyunsaturated fat,” says Dr. Krauss.
Don’t interpret the new research on saturated fat as an excuse to go on a bacon cheeseburger binge. Dr. Krauss says that to conclude that saturated fats aren’t harmful is a big oversimplification. “To extrapolate from our analysis about saturated fat to all foods containing saturated fat is a direction I think we need to move away from,” he says.
For one thing, he explains, there may be other unhealthful ingredients lurking in saturated fat–filled foods.
More generally, he adds, emphasizing dietary patterns and their relationship to disease—rather than a tight focus on certain aspects of food chemistry—is likely to lead to a better understanding of nutrition and health.
