Because of the high concentration of sugars, so-called ‘light foods' can promote the risk of metabolic diseases and the accumulation of fat in the liver, as well as catalyzing the increase in body weight. The demonstration in a study conducted on rats.

Researchers at the University of Georgia (United States) have shown that so-called "light" foods are not as healthy as they are generally advertised and consequently conceived by the public. In fact, not only would they promote weight gain – the opposite effect of the one desired by those who buy them – but because of the high sugar content they can cause metabolic and liver problems, as well as impact on the intestinal bacterial flora. The researchers, coordinated by Professor Krzysztof Czaja, professor of Veterinary Biosciences and Diagnostic Imaging at Athens University, have come to this conclusion after a series of experiments and analyzes conducted on three distinct groups of rats.

The first group was fed with a diet rich in fats and sugars; the second with low-fat and high-sugar foods (such as light foods) and the third with a balanced diet. After four weeks of monitoring, interesting and unexpected details emerged for the second group, where not only was a significant increase in body weight, but also an important accumulation of fat in the liver. "It's a very dangerous situation, because a liver with more fat mimics the effect of non-alcoholic fatty liver disease," said the lead author of the research. The latter is a pathology resulting from the continuous accumulation of fats in the liver, and in the most serious cases can trigger the same effects related to alcohol abuse.


The diets of the first and second groups also determined a chronic inflammation of the intestinal tract and of the brain, with a specific alteration in the communication between the vagus nerve and the central nervous system. The greatest risk for the so-called light foods lies in the fact that being less caloric they satiate less, so people consume them more and, moreover, having more sugars, they can catalyze the onset of diabetes and other metabolic diseases. Not to mention that the accumulation of fat detected by researchers is comparable to that of a balanced diet but with the intake of less than half of the calories. The researchers therefore suggest to always give priority to a balanced diet, and of course to consult with a dietitian/nutritionist to face any weight problem, keeping away the so-called do-it-yourself diets. The details of American research have been published in Physiology & Behavior.