According to Marya Wegenka at Vanderbilt University, the 48-Hour Hollywood Miracle Diet does not work as effectively as it claims. She notes that there are also potential health risks associated with this and similar crash diets that involve extremely low-calorie intake.
Wegenka explains that the 48-Hour Hollywood Miracle Diet restricts calorie intake to 400 calories per day, and is intended to help users lose up to ten pounds in two days. She notes that this kind of very low-calorie diet is usually undertaken by only the morbidly obese, and only under a doctor's supervision. Otherwise, healthy weight-reduction plans typically help users to lose one to two pounds per week.
She points out that the 48-Hour Hollywood Miracle Diet is not FDA-approved due to it having no fat, no protein, and insufficient vitamins and minerals. According to Wegenka, very low calorie diets may decrease metabolic rate as well as induce metabolic complications. She states that there is a small chance that the 48-Hour Hollywood Miracle Diet may induce gallstones in those who follow the diet. She describes this diet as a controlled form of starvation that may help people lose one to two pounds per week, far short of the ten pounds in two days that is advertised. There is also a risk of binge eating when someone comes off of any very low-calorie diet.