Most of the conventional weight loss programs use a combination of exercise and low-calorie restrictions to help people lose weight. With these traditional methods, calories are typically reduced to about 1,500 per day. However, for people who are severely obese, there is another alternative “short-term” method for weight loss. It’s called the “very low-calorie diet”, or VLCD. In many VLCD programs, formulas such as OPTIFAST are commercially prepared to include only 800 calories (or even less) that replace all daily food intake.
When used with appropriate medical supervision in people who are obese (BMI greater than 30), very low-calorie diets are typically safe. VLCDs should be reserved for people who have obesity-related medical complications when their BMI is 27 to 30. A VLCD is not advised for everyone; so your medical weight loss doctor will have to determine if the diet is right for you. Breastfeeding and pregnant women should not use a very low-calorie diet. Additionally, the VLCD’s are not typically recommended for children, adolescents, or people over 50, unless under a special treatment program.
For moderately to severely obese people, a very low-calorie diet may enable them to lose approximately three to five pounds a week. Over a 12 week period the average weight loss is about 44 pounds. This amount of weight loss can help improve obesity-related health conditions, such as high blood pressure, high cholesterol, and type-2 diabetes. It’s important to note that VLCDs are for short-term use. To increase and maintain weight loss, exercise and behavioral therapy should be introduced.
The side effects of a very low-calorie diet are generally minor and include nausea, diarrhea, constipation, and fatigue. Another potential side effect is gallstone formation, which occurs when obese people lose weight rapidly regardless of the method used.
It is difficult to obtain all the nutrition you need from a diet of as few as 800 calories. For this reason using a complete nutritional supplement such as OPTIFAST is critical. Medical meal replacement formulas like this contain the vitamins, minerals and nutrition that you need and is almost impossible to get from only 800 calories of normal food.
While a VLCD is an effective weight loss tool, weight regain at completion of the diet is almost inevitable unless behavioral change and nutrition education and advice is also part of the program. Without this, the long-term commitment to healthy eating and regular physical activity required to prevent the weight from coming back is difficult to achieve.