A fad diet is a diet that suddenly becomes popular, usually because it promises people that they will lose a lot of weight overnight. Although dieters may really show weight loss from a fad diet, they will almost certainly get back the weight if their usual eating habits   remain unchanged. Moreover, fad diets continuously call for special products of questionable value or for "health foods" that may cost twice as much as supermarket  foods. Worse yet, certain fad diets don't include nutrients good for health. People have been known to become very ill as a result of following medically unhealthy diets. The worse fact of fad diets, though, is that they keep people who are over-weight or sick from receiving the medical care that they truly need. In the writer's opinion, fad diets  _  .
are very helpful are not healthy diet won't cost much include lots of nutrients