Mouse Study Suggests That Dietary Fat, Not Carbs, Drives Obesity

During the 1980s and 1990s, it was widely accepted that the most important factor in weight gain is the fat content of our diets. However, in the new millennium it was suggested that this focus on fat was misplaced, and that, in fact, the main factor driving obesity was our carbohydrate intake – notably, our intake of refined carbohydrates like sugars. Several hugely popular books were published in this period suggesting that eating fat might actually protect us from obesity. Most recently, however, attention has turned to protein, with the hypothesis that people eat food mostly to obtain protein rather than energy. According to this idea, when the protein content of our diet falls, we eat more food to meet our target protein intake. That makes us consume too many calories and we get fat. Since our food consists of fat, protein and carbohydrates – and at different times all three have been implicated in making us obese – it is difficult to know what to eat to stay slim. Part of the problem is that it is very difficult to do human studies that control food intake long enough to determine what dietary factors cause weight gain. Studies on animals similar to us, however, can suggest possible answers. The result of this enormous study was unequivocal – the only thing that made the mice get fat was eating more fat in their diets. Carbohydrates, including up to 30% of calories coming from sugar, had no effect. Combining sugar with fat had no more impact than fat alone. There was no evidence that low protein (down to 5% of the total calories) stimulated greater intake, suggesting there is no protein target. The researchers believe that dietary fat caused weight gain because fat in the diet uniquely stimulated the reward centers in the brain, thus causing greater intake of calories. https://www.technologynetworks.com/proteomics/news/mouse-study-suggests-that-fat-not-carbs-drives-obesity-306261?utm_campaign=Newsletter_TN_BreakingScienceNews&utm_source=hs_email&utm_medium=email&utm_content=64464121&_hsenc=p2ANqtz--fAtIz81TylMz_zO6bm6_oGA9xDa8Irha55Ar7Zzub61ZkhFekVuPa-mquYL1P0lviuW90iGS_52e6AkrppRxosen0CQ&_hsmi=64464121