JJ Virgin warns that aggressive calorie cutting causes muscle loss and slows metabolism, making it unsustainable long-term. She recommends losing 0.5–1% of body weight per week to preserve muscle, reframing weight loss as a shift in body composition rather than just dropping pounds.
Speaking of caloric restriction, that is another place where people can mess up as they try to do too much caloric restriction, and it is not sustainable. And remember, we talked about losing muscle mass. That is the key driver. One of the big things that will make you lose muscle mass is just cutting those calories way too low. Plus, you know, who can do that for long? So here's what I like to do. You should be thinking of losing somewhere between 0.5 to 1% of your body weight per week because that's going to help you hold on to that muscle mass. And really what you want to do when you're losing weight you really want to change your body composition. Losing weight's code for improving body composition, holding onto or building muscle while you're putting on fat. If you lose muscle, you are going to slow down your metabolism, right? This naturally happens with weight loss anyway, but it will be more dramatic if you lose more muscle. If you keep more muscle on, you're going to have a better metabolism.
