One of the bigger dangers of fad dieting is that we often always cut something out of our diet we truly need to stay healthy. Typically it is a matter of reducing the amount of carbohydrates, fats or calories that we are eating. Yes, it does matter how much of these things we are eating, but severely restricting ourselves from anything that our body needs is not going to be good for us. Our body loses weight as a response to this because we are putting it into an unhealthy condition. Whenever we go back to eating a regular diet, our body simply goes back to the weight that it is used to carrying around.
Another thing that you need to be concerned about is your metabolism. Your metabolism is the furnace that keeps your body running and helps you to burn calories. If you fad diet and end up messing up your metabolism by speeding it up and slowing it down continuously, it may give up on you altogether. That is why many individuals that have been dieting for years often find it difficult to lose any weight at all. They damaged the very process that helps them to lose weight in the first place.