Aaron E. Carroll
THE NEW HEALTH CARE APRIL 15, 2016
There was a lot of news this week about a study, published in the medical journal BMJ, that looked at how diet affects heart health. The results were unexpected because they challenged the conventional thinking on saturated fats.
And the data were very old, from the late 1960s and early 1970s.
This has led many to wonder why they weren’t published previously. It has also added to the growing concern that when it comes to nutrition, personal beliefs often trump science.
Perhaps no subject is more controversial in the nutrition world these days than fats. While in the 1970s and 1980s doctors attacked the total amount of fat in Americans’ diets, that seems to have passed. These days, the fights are over the type of fat that is considered acceptable.
Most of our fat comes from two main sources. The first is saturated fats. Usually solid at room temperature, they’re in red meat, dairy products and partly in chicken. The second is unsaturated fats, usually softer and more liquid at room temperature. They’re in fish, nuts and vegetable oils. Many doctors and nutritionists still argue, quite strongly, that the key to health is to emphasize the unsaturated fats. Others believe that’s misguided.
This week’s news came to us by way of a randomized controlled trial, which I’ve argued repeatedly is the best kind of study to determine how one thing causes another.
