Most fad diets do more harm than good. Most of these diets share the same characteristics:

• Their rise in popularity is rapid
• They distort or ignore proven nutrition principles
• They have a special appeal or prestige
• They make grand promises of rapid weight loss
• They promote engineered fasts
• They promote a particular food or special diet
• They quote questionable, self-sponsored or biased science
• They relieve the dieter of all responsibilities and decisions
• They seldom include the full variety of foods needed by the body
• They sound easy

There are virtually hundreds of fad diets. Although these diets vary widely in composition, they all have the potential of leading to nutrient deficiencies and dangerous side effects.

The majority of them fall into one of the following categories:

• Low carbohydrate diets
• High carbohydrate diets
• Fasts
• Protein sparing modified fasts