A new study has shed light on the eating patterns that can develop in already obese patients making them more likely to overeat. Researchers at Penn State Medical College have demonstrated a link between the tongue, the ability to taste sweet foods and the likelihood of developing obesity. Previous studies have shown that the obese have a decreased sensitivity to sweet foods. The researchers took rats with this taste insensitivity associated with the overweight, and compared their eating habits with lean, healthy rats. They discovered that while the OELFT rats (those with the damaged taste) started out slim, they began gaining weight, apparently because the signal that the brain receives telling it that the body is satisfied was not being sent.
Compared with the healthy rats, the OELFT rats had 50% less neurons in their tongue sending signals when fed a low-level sucrose concentrate. However, when eating food with a higher concentration of sucrose, the area of the brain that receives the tongue‘s signals indicated that their nerve cells worked more vigorously than those of the healthy animals. Essentially, the tests showed that the rats with less taste sensitivity responded weakly to lower sugar levels, and more strongly to high sugar levels, meaning that they ate more sugar and got fatter. This leads to the conclusion that as the obese develop an insensitivity to sugar, they will naturally crave more sugary foods. As the leading researcher Dr. Hanjal explained, “When you have excess body weight, the brain is supposed to tell you not to eat more, or not choose high caloric meals… this control apparently fails… and we want to find out how the sense of taste drives up food intake.”
The study indicates that those who are already overweight are likely to get trapped in a terrible cycle, where the more they eat the less satisfied they feel. As anyone with an unhealthy relationship with food will tell you, overeating is often related to the emotions. Some don’t eat enough as a means of gaining control when life feels unstable; some eat far too much as a way of comforting themselves . Dr. Hanjal’s team has shown that on top of these emotional triggers, there may be a physical cause to overeating, the genuine feeling that the body has not had enough sugar.