Many people believe that losing weight is simply a matter of eating less, but weight management specialist Dr. Hsu Shu-Hua warns that lack of sleep can seriously undermine dieting efforts — often causing the body to lose muscle rather than fat. Studies show that among people who restrict their calories, those who sleep poorly can lose up to 70% of their weight from muscle instead of fat.
Sleep deprivation also impairs the brain’s ability to control self-discipline. Dr. Hsu explains that this raises ghrelin, the hunger hormone, making people crave sugary and fatty foods like bubble tea or fried snacks. Over time, this not only reduces the effectiveness of dieting but can lead to binge-eating that stores fat around the abdomen and increases visceral fat.
Additionally, insufficient sleep triggers excess stress hormone production, putting the body into a “storage mode” that makes burning fat harder. In other words, even with strict calorie control, lack of sleep can cause you to lose muscle instead of fat, leaving your body less toned and shapely.
Dr. Hsu recommends that adults aim for at least seven hours of sleep each night. Proper rest protects muscle, stabilises hormones, curbs appetite, and boosts fat loss. For effective and healthy weight loss, paying attention to sleep is just as important as controlling diet.
