There are two times a year when people decide that losing weight is imperative...immediately. One of those times is coming up next month, when the unofficial start of summer kicks off with a wave of crash diets, detox diets and whole-body cleanses. The swimsuit season is second only to New Year’s as a time when otherwise healthy, intelligent people put themselves through crazy restriction diets and extreme exercise programs. What they don’t realize is that crash dieting doesn’t work, and it may do some serious damage to your health. So to answer the headline question, yes, crash diets are bad for you.