Fad Diet Types

In 2006, Janet Jackson dropped an amazing 60 lbs. in four months. To do it, she went on a strict diet of just egg whites, chicken and asparagus. Beyonce lost 20 lbs. in just two weeks by following the lemonade diet -- most solid foods are banned for the duration of this diet. With so many celebrities endorsing fad diets, it's no surprise that fad diets in all types and forms are becoming more popular.

Gimmicky Diets

Gimmicky diets require the use of a particular item or product in order to lose weight. Examples include diet teas, weight loss "vitamins" and other pills. In 1998, author Alan R. Hirsch came up with a diet called "scensational weight loss," in which he promises you'll lose weight by modifying the food smells around you. Then there's also the hCG diet, which brings the ouch factor into play. The diet claims that by getting daily injections of hCG -- the pregnancy hormone --- you'll speed up your metabolism and increase your weight loss.

Crash Diets

Crash diets are those that allow you to eat only a very small amount of food. Some are clear about the food consumed, while others hide the total calorie count behind gimmicks. For example, the cabbage soup diet is a crash diet that allows about 800 or 900 calories per day. This is way below the recommended daily intake of 1,200 calories per day. Other crash diets include the grapefruit diet, the cookie diet and the Eat QOD, which involves eating every other day.

Liquid Diets

Liquid diets are usually crash diets, as well. Many require you to drink canned shakes as a replacement for your regular meals. These shakes are usually made with milk or soy milk and come in flavors such as chocolate, strawberry and vanilla. Shakes contain about 200 calories per can, so you're naturally cutting calories. This means the weight loss won't necessarily come because of the "magic shake" but because you're consuming a lower amount of calories. Some liquid diets market themselves as "cleansing diets." These usually focus on natural fruit and vegetable juices or require you to drink a lot of water, sometimes flavored with lemon or other products.

Food-Group Diets

Some of the most famous diets in the market are food-group diets. This is the case of low-carb diets such as Atkins and South Beach. Other diets focused on food groups are based on more complicated exclusions. The blood type diet, for example, recommends type O people to eat mostly proteins, while type A should be vegetarians.