Diet plans promising rapid weight loss with minimal effort are constantly springing up. However, losing weight isn't as simple as eating bowls of cabbage soup or avoiding starchy vegetables. Fad diets like Atkins, the Cabbage Soup Diet, the South Beach Diet, and the Grapefruit Diet often provide inadequate nutrition and lead to short-term weight loss.

The Cabbage Soup Diet
The Cabbage Soup Diet began circulating via fax messages during the 1980s. Sometimes called the General Motors Diet or the TJ Miracle Soup Diet, the plan claims to help you shed up to 10 pounds in seven days. As the name suggests, the diet involves consuming large amounts of fat-free cabbage soup. You may also eat certain fruits and vegetables, chicken or beef, and brown rice on different days. It's recommended that you return to a normal eating plan for two weeks before repeating the Cabbage Soup Diet.

Many experts are critical of the Cabbage Soup Diet. Most of the weight you lose by following this diet is due to water loss--not fat loss. Your fluid levels will normalize and your weight will increase when you return to a normal diet with sufficient nutrients, calories, protein, and carbohydrates. The blandness of the soup makes it difficult for most people to stick to the diet and more appealing recipes are usually high in sodium.

The verdict: This diet doesn't help you make the necessary lifestyle changes required for permanent weight loss.

Grapefruit Diet
The Grapefruit Diet is a 12-day plan promising 10 pounds of weight loss. The diet suggests that grapefruit helps your body burn fat more efficiently. Many variations of this low-carbohydrate diet exist, but most require you to consume a half of grapefruit or glass of unsweetened grapefruit juice with each meal. A typical breakfast consists of eggs, bacon, black coffee, and a grapefruit or grapefruit juice. Dinner usually includes vegetables, unlimited meat or fish, and grapefruit. The diet plan calls for a drastic reduction in daily calories--sometimes as few as 800 a day. Eating this few of calories will cause weight loss with or without grapefruit.

The verdict: While eating a grapefruit with each meal is a good way to include more fruit in your diet, grapefruits won't magically cause your body to burn more fat. Just as with the cabbage soup diet, weight loss will be short-term.

Atkins Diet
The Atkins Diet, developed by Robert Atkins, MD, allows you to eat as much fat and protein--eggs, cheese, butter, cream, oil, meat, and other foods usually off-limits to dieters--as you'd like. Carbohydrates, on the other hand, are strictly limited. You may have 20 carbs a day during the first stage of the diet plan. Normally, you'd eat about 300 carbohydrates a day. Restricting carbohydrates in this manner triggers ketosis, a process where your body burns stored fat instead of gaining energy from carbohydrates. The diet also suggests that ketosis helps suppress your appetite.

While moderately reducing carbohydrate intake is an effective step toward weight loss, the restrictions called for in the Atkins approach can have adverse effects. Many nutrient-rich foods including legumes, starchy vegetables, fruits, and grains are absent from the diet plan, and the lack of fiber may lead to constipation. High-fat diets also put you at risk for developing gout, kidney stones and increase bad cholesterol levels.

The verdict: Prolonged periods of ketosis can cause dehydration, fatigue, nausea, and loss of potassium. With these "bonuses," the weight you might lose wouldn't be worth it.

South Beach Diet The South Beach Diet, created by cardiologist Arthur Agatston, is another low-carbohydrate diet with a strict beginning phase where most carbs, including fruit, are restricted. During the first phase, you can have normal-sized portions of meat, poultry, and fish and plenty of vegetables, eggs, cheese, and nuts. More food choices can be incorporated into your diet in later phases.

Removing bad carbohydrates--those with a high glycemic index rating--from your diet, keeps your body from developing an insulin resistance that causes you to burn less fat. Completely avoiding groups of food in this manner isn't necessary for weight loss.

The verdict: Permanent weight loss requires moderation and a well-balanced diet with plenty of fruits, vegetables, and healthy protein choices.

The Bottom Line
It's impossible to achieve permanent weight loss by following diet plans encouraging you to avoid entire groups of food. Healthy weight loss involves making healthy lifestyle changes. Make a commitment to eat well-balanced meals and include exercise in your daily routine. A fad diet may jumpstart your weight loss, but it won't help you keep off the pounds.