Limit high intensity workouts like spinning and cross fit, Dr. Gioffre says. These exercises are fine in moderation. “But I can’t tell you how many times I have had clients who spin every day hoping to lose weight.” At first, they will lose some weight, as this happens when any change occurs. But as you continue, the body will hit a plateau, or even worse, add some weight, he adds. The reason is that high intensity exercises like these produce lactic acid as a byproduct of working out. “When you spin, for example, the body is working anaerobically (without oxygen), and in the absence of oxygen, to get energy, it burns sugar. The lactic acid that is produced is toxic, acidic, and if you don’t give your body minerals to neutralize the acid, the body will retain fat instead.”