During the Intensive Level of the OPTIFAST Program, weight loss averages 1.0 to 2.5kg/week with an average total loss of 20kg after 12 to 16 weeks1, 2, 3.
It is common to see a larger amount of weight loss in the first week of the Program. The weight loss in the second week will give you and your patient an idea of what to expect ongoing. Weight loss will vary between individuals and will also depend on physical activity levels. For example, both men and individuals with a higher BMI will have a greater reduction in weight because they have higher energy expenditures due to their bigger stature and relatively more lean body mass.
The table and graph below highlight the expected rates of weight loss based on BMI while following the OPTIFAST VLCD Intensive Level.
Expected rate of weight loss2
Weight loss during an 8 week period2
1. Delbridge, E. & Proietto, J. Asia Pacific Journal of Clinical Nutrition, 2006;15(Suppl): 49-54.
2. Mustajoki, P. & Pekkarinen, T.,. Obesity Reviews, 2001;(2):61-72 (article can be accessed here)
3. Obesity, T.N.T.o.t.P.a.T.o., Very Low-Calorie Diets. J Am Medical Assoc, 1993. 270(8): p. 967-974.