The cabbage soup diet is not effective for long-term weight loss, according to WebMD. Dieters may lose a few pounds quickly as the daily caloric intake on the diet is only 1,000 calories, which is half of the recommended amount for adults.
The cabbage soup diet does not provide the nutrients the body needs to stay healthy, notes WebMD. The initial weight loss that occurs is mainly water weight, which is regained as soon as a dieter begins eating regularly again. The cabbage soup diet and other low-calorie diets are not recommended by health care experts, unless under a doctor's supervision.