To eat fat or not to eat fat

For generations, physicians, dieticians, nutritionists and dieters have argued about just how bad fat really is for you. That is all old news. But a new study by researchers at the Vanderbilt University School of Medicine has sought to determine why a diet high in fat makes people so … well, fat.

It turns out that eating fatty foods impairs the brain’s ability to sense that you are full. The human body isn’t designed to overeat. Our need to feed is controlled by our brain via the central nervous system. Our brain tells us to eat when we are hungry, and to stop eating when we are full. The hormone insulin regulates the process, signaling to your brain that your stomach is full, which lets your body know that it needs to stop eating.

The Vanderbilt researchers found that high-fat foods like that handful of food chain French fries, interfere with insulin signaling. The fat interrupts your stomach’s communication to your brain — ‘Hey, I’m full! No more fries!’ — and instead, you reach for another handful (and maybe another after that).

This interference in insulin signaling leads to a condition known as hyperphagia, an abnormally increased appetite for food, which means that you keep eating and eating, even when you are technically full. Hyperphagia also interferes with hormones that regulate your metabolism, which can lead to a decreased metabolism. A decreased metabolic rate means that your body burns calories less efficiently, so you will gain even more weight from overeating. This can easily lead to obesity.

Scientists already knew that obesity was potentially caused by signal interference, but this study, published Sept. 21 in the journal Heliyon illustrated the mechanism by which fatty foods cause this signal interference.

Overall, the outlook for high-fat diets is quite grim. But before you swear off French fries forever, keep in mind that this was not a clinical trial conducted on human subjects — the test subjects were mice. However, the results might make you re-think your next stop at a drive-thru — are the fries worth messing with your head?