WIN Weight-control Information Network

Very-Low-Calorie Diets

Obesity affects nearly

one-third of adults in the

United States, increasing

their risk for diabetes,

high blood pressure, and

heart disease. Traditional

weight loss methods

include low-calorie diets

from 800 to 1,500

calories a day and

regular physical activity.

Health care providers

sometimes consider an

alternative method for

bringing about

significant short-term

weight loss in patients

who are moderately to

extremely obese: the

very-low-calorie diet.

U.S. DEPARTMENT

OF HEALTH AND

HUMAN SERVICES

What is a very-low-calorie diet (VLCD)?

VLCDs are commercially prepared formulas of about 800 calories that replace

all usual food intake for several weeks or months. VLCDs are not the same as

over-the-counter meal replacements, which are meant to substitute for one or two

meals a day. VLCDs, when used under proper medical supervision, effectively

produce significant short-term weight loss in patients who are moderately to

extremely obese.

Studies have shown that meal replacements at higher calorie levels (800 – 1000

calories) produce weight loss similar to that seen with much lower calorie levels,

probably due to better compliance with the diet. In addition, VLCDs are usually

part of weight-loss treatment programs that include other techniques such as

behavioral therapy, nutrition counseling, physical activity, and/or drug treatment.

Who should use a VLCD?

VLCDs are intended to produce rapid weight loss at the start of a weight-loss

program in patients with a body mass index (BMI) greater than 30. BMI

correlates significantly with total body fat content. It is calculated by dividing

weight in kilograms by height in meters squared, or by dividing weight in pounds

by height in inches squared and multiplying by 703.

Use of VLCDs in patients with a BMI of 27 to 30 should be reserved for those

who have medical complications resulting from their overweight. VLCDs are not

recommended for pregnant or breastfeeding women. VLCDs are not appropriate

for children or adolescents, except in specialized treatment programs.

Very little information exists regarding the use of VLCDs in older people.

Because people over age 50 already experience normal depletion of lean body

mass, use of a VLCD may not be warranted. Also, people over 50 may not

tolerate the side effects associated with VLCDs because of preexisting medical

conditions or need for other medications. Physicians must evaluate on a case-bycase basis the potential risks and benefits of rapid weight loss in older individuals,

as well as in people with significant medical problems or who are on medications.

Health benefits of a VLCD

A VLCD may allow a patient who is moderately to extremely obese to lose about

3 to 5 pounds per week, for an average total weight loss of 44 pounds over 12

weeks. Such a weight loss can rapidly improve obesity-related medical

conditions, including diabetes, high blood pressure, and high cholesterol.
NIH Publication No. 03-3894

January 2003

Weight-control

Information

Network

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Internet: www.niddk.nih.gov/

health/nutrit/nutrit.htm

The Weight-control Information

Network (WIN) is a national service

of the National Institute of Diabetes

and Digestive and Kidney Diseases

of the National Institutes of Health,

which is the Federal Government’s

lead agency responsible for

biomedical research on nutrition

and obesity. Authorized by Congress

(Public Law 103-43), WIN provides

the general public, health

professionals, the media, and

Congress with up-to-date, sciencebased health information on weight

control, obesity, physical activity,

and related nutritional issues.

WIN answers inquiries, develops and

distributes publications, and works

closely with professional and patient

organizations and Government

agencies to coordinate resources

about weight control and related

issues.

Publications produced by WIN are

reviewed by both NIDDK scientists

and outside experts. This fact sheet

was also reviewed by Rena Wing,

Ph.D., Professor, Brown University

and University of Pittsburgh School

of Medicine.

This publication is not copyrighted. WIN

encourages users of this fact sheet to duplicate

and distribute as many copies as desired.

This fact sheet is also available at

www.niddk.nih.gov/health/nutrit/nutrit.htm.

National Institute of Diabetes and

Digestive and Kidney Diseases

Adverse effects of a VLCD

Many patients on a VLCD for 4 to 16 weeks report minor side effects such as

fatigue, constipation, nausea, and diarrhea, but these conditions usually improve

within a few weeks and rarely prevent patients from completing the program. The

most common serious side effect is gallstone formation. Gallstones, which often

develop anyway in people who are obese, especially women, are even more

common during rapid weight loss. Research indicates that rapid weight loss may

increase cholesterol levels in the gallbladder and decrease its ability to contract

and expel bile. The drug ursodiol can prevent gallstone formation during rapid

weight loss, but is not often used for this purpose.

Maintaining Weight Loss

Studies show that the long-term results of VLCDs vary widely, but weight regain

is common. Combining a VLCD with behavior therapy and physical activity may

help increase weight loss and slow weight regain. In the long term, however,

VLCDs are no more effective than more modest dietary restrictions.

For most people who are obese, obesity is a long-term condition that requires

a lifetime of attention even after formal weight loss treatment ends. Therefore,

health care providers should encourage patients who are obese to commit to

permanent changes of healthier eating, regular physical activity, and

an improved outlook about food.

Endnote: This fact sheet is an updated, modified version of a previously

published review article appearing in the August 25, 1993 issue of the Journal

of the American Medical Association. Both the review article and this fact sheet

were developed with the advice of the National Task Force on Prevention and

Treatment of Obesity.

Additional Reading

Dieting and Gallstones. NIH Publication No. 02-3677. February 2002.

Available from WIN.

Active at Any Size. NIH Publication No. 00-4352.

March 2001. Available from WIN.

Healthy Eating and Physical Activity Across Your Lifespan: Better Health

and You. NIH Publication No. 02-4992. June 2002. Available from WIN.