Very Lowcalorie Diets

U.S. Department of Health 

and Human Services

NATIONAL INSTITUTES OF HEALTH

NIH...Turning Discovery Into Health®

 WIN Weight-control Information Network

A very low-calorie diet (VLCD) is not just any 

diet that is low in calories. It is a special type of 

diet that replaces all of your meals with prepared 

formulas, often in the form of liquid shakes. 

A VLCD may be used for a short time to promote 

quick weight loss among some people who are 

considered to be obese. The diet requires close 

care from your doctor and is usually combined 

with other ways to lose weight (see box).

This fact sheet will tell you more about the risks 

and benefits of this type of diet. Do not go on a 

VLCD on your own. If you need to lose weight, 

talk to your health care provider about the 

approaches that may work best for you.

How is obesity treated?

Obesity is treated using one or more of these 

strategies:

 a diet low in calories

 increased physical activity

 behavior therapy 

 prescription medications 

 weight-loss surgery

For more information, see the WIN fact sheet 

Weight Loss for Life, listed under Resources.

What is a VLCD?

A VLCD is a special diet that provides up to 800 

calories per day. VLCDs use commercial formulas, 

usually liquid shakes, soups, or bars, which replace 

all your regular meals. These formulas are not the 

same as the meal replacements you can find at 

grocery stores or pharmacies, which are meant to 

replace one or two meals a day. 

Depending on a number of factors, healthy adults 

need different amounts of calories to meet their 

daily energy needs. A standard amount is about 

2,000 calories. VLCDs provide far fewer calories 

than most people need to maintain a healthy 

weight. This type of diet is used to promote quick 

weight loss, often as a way to jump-start an obesity 

treatment program. 

VLCD formulas are designed to provide all of the 

nutrients you need while helping you lose weight 

quickly. However, this type of diet should only be 

used for a short time—usually about 12 weeks.

Should I use a VLCD to lose weight?

Most people who need to lose weight should not 

use a VLCD. For many of them, a low-calorie 

diet (LCD) may work better (see box on next page).

VLCDs may be used to promote rapid weight 

loss among adults who have obesity. Health care 

providers must review risks and benefits on a 

case-by-case basis.

In general, VLCDs are not appropriate for children. 

In a few cases, they may be used with some 

adolescents who are being treated for obesity.
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The Low-calorie Diet (LCD) 

An LCD limits calories, but not as much as a 

VLCD. A typical LCD may provide

 1,000–1,200 calories/day for a woman

 1,200–1,600 calories/day for a man

The number of calories may be adjusted based 

on your age, weight, and how active you are.

An LCD usually consists of regular foods, but 

could also include meal replacements. As a 

result, you may find this type of diet much 

easier to follow than a VLCD. 

In the long term, LCDs have been found to 

lead to the same amount of weight loss as 

VLCDs.

Not much is known about the use of VLCDs to 

promote weight loss among older adults. Some 

people over age 50 may have medical issues that 

may not make them good candidates for this type 

of diet.

What are the health benefits of a VLCD?

A VLCD may allow you to lose about 3 to 5 

pounds per week. This may lead to an average 

total weight loss of 44 pounds over 12 weeks. 

Such a weight loss can rapidly improve medical 

conditions linked to obesity, including diabetes, 

high blood pressure, and high cholesterol.

The rapid weight loss experienced by most people 

on a VLCD can be very motivating. Patients who 

participate in a VLCD program that also includes 

lifestyle changes may lose about 15 to 25 percent 

of their initial weight during the first 3 to 6 months. 

They may maintain a 5 percent weight loss after 4 

years if they adopt a healthy eating plan and physical 

activity habits.

What are the health risks of a VLCD?

Doctors must monitor all VLCD patients 

regularly—ideally every 2 weeks in the initial 

period of rapid weight loss—to be sure patients 

are not experiencing serious side effects.

Many patients on a VLCD for 4 to 16 weeks 

report minor side effects such as fatigue, constipation, 

nausea, or diarrhea. These conditions usually 

improve within a few weeks and rarely prevent 

patients from completing the program. 

The most common serious side effect is gallstones. 

Gallstones, which often develop in people who 

are obese, especially women, may be even more 

commonly developed during rapid weight loss. 

Some medicines can prevent gallstones from 

forming during rapid weight loss. Your health 

care provider can determine if these medicines 

are appropriate for you. For more information, 

see the WIN fact sheet on dieting and gallstones, 

listed under Resources.

Will I regain the weight?

Although the long-term results of VLCDs vary 

widely, weight regain is common. To prevent 

weight regain, the VLCD should always be 

combined with other ways to lose weight and 

with an active follow-up program.

For most people who have obesity, the condition 

is long term and requires a lifetime of attention 

even after formal methods to treat the obesity 

end. You may need to commit to permanent 

changes of healthier eating, regular physical 

activity, and an improved outlook about food.
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Research

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) 

conducts and supports a broad range of basic and clinical obesity research. More 

information about obesity research is available at http://www.obesityresearch.nih.gov.

Participants in clinical trials can play a more active role in their own health care, 

gain access to new research treatments before they are widely available, and 

help others by contributing to medical research. For more information, visit

http://www.clinicaltrials.gov. 

Resources

Additional Reading from the Weight-control Information Network

The following publications are available online at http://www.win.niddk.nih.gov/

publications and also by calling WIN toll-free at 1–877–946–4627:

■ Active at Any Size explains the benefits of regular physical activity and 

describes activities that people who are overweight or obese can enjoy safely. 

■ Better Health and You: Tips for Adults helps adults plan steps toward eating 

healthier and being more physically active. This brochure also explains the 

benefits of getting healthy and the harmful effects of being overweight.

■ Choosing a Safe and Successful Weight-loss Program offers guidelines to 

help readers talk with their health care providers about weight-loss programs.

■ Dieting and Gallstones answers common questions about the causes, 

effects, and treatment of gallstones. 

■ Weight Loss for Life discusses the benefits of weight loss and ways to develop 

healthy eating and physical activity plans. In addition, the differences between 

the two types of formal weight-loss programs—clinical and nonclinical—are 

discussed.

Additional Resources

■ 2008 Physical Activity Guidelines for Americans

http://www.health.gov/paguidelines/guidelines

■ Dietary Guidelines for Americans, 2010

http://health.gov/dietaryguidelines

■ National Diabetes Education Program

http://yourdiabetesinfo.org

Inclusion of resources is for information only and does not imply endorsement 

by NIDDK or WIN.

Weight-control 

Information Network

1 WIN Way

Bethesda, MD 20892–3665

Phone: 202–828–1025

Toll-free number: 1–877–946–4627

Fax: 202–828–1028

Email: win@info.niddk.nih.gov

Internet: http://www.win.niddk.nih.gov

http://www.facebook.com/win.niddk.nih.gov

The Weight-control Information Network 

(WIN) is a national information service 

of the National Institute of Diabetes and 

Digestive and Kidney Diseases (NIDDK), 

part of the National Institutes of Health 

(NIH). WIN provides the general public, 

health professionals, and the media with 

science-based, up-to-date, culturally 

relevant materials and tips. Topics include 

healthy eating, barriers to physical activity, 

portion control, and eating and physical 

activity myths. Publications produced 

by WIN are carefully reviewed by both 

NIDDK scientists and outside experts. 

This publication is not copyrighted. 

WIN encourages you to copy and 

share as many copies as desired. This 

brochure is also available at 

http://www.win.niddk.nih.gov.

NIH Publication No. 03–3894

August 2008

Updated December 2012