Obesity

What is the role of diet in the treatment of obesity?

The first goal of dieting is to stop further weight gain. The next goal is to establish realistic weight-loss goals. While the ideal weight corresponds to a BMI of 20-25, this is difficult to achieve for many people. Thus, success is higher when a goal is set to lose 10%-15% of baseline weight as opposed to 20%-30% or greater. It is also important to remember that any weight reduction in an obese person would result in health benefits.

One effective way to lose weight is to eat fewer calories. One pound is equal to 3,500 calories. In other words, you have to burn 3,500 more calories than you consume to lose 1 pound. Most adults need between 1,200-2,800 calories per day, depending on body size and activity level to meet the body's energy needs.

If you skip that bowl of ice cream, then you will be one-seventh of the way to losing that pound! Losing 1 pound per week is a safe and reasonable way to take off extra pounds. The higher the initial weight of a person, the more quickly he/she will achieve weight loss. This is because for every 1 kilogram (2.2 pounds) of body weight, approximately 22 calories are required to maintain that weight. So for a woman weighing 100 kilograms (220 pounds), he or she would require about 2,200 calories a day to maintain his or her weight, while a person weighing 60 kilograms (132 pounds) would require only about 1,320 calories. If both ate a calorie-restricted diet of 1,200 calories per day, the heavier person would lose weight faster. Age also is a factor in calorie expenditure. Metabolic rate tends to slow as we age, so the older a person is, the harder it is to lose weight.

There is controversy in regard to carbohydrates and weight loss. When carbohydrates are restricted, people often experience rapid initial weight loss within the first two weeks. This weight loss is due mainly to fluid loss. When carbohydrates are added back to the diet, weight gain often occurs, simply due to a regain of the fluid.

General diet guidelines for achieving and (just as importantly) maintaining a healthy weight

  • A safe and effective long-term weight reduction and maintenance diet has to contain balanced, nutritious foods to avoid vitamin deficiencies and other diseases of malnutrition.
  • Eat more nutritious foods that have "low energy density." Low energy dense foods contain relatively few calories per unit weight (fewer calories in a large amount of food). Examples of low energy dense foods include vegetables, fruits, lean meat, fish, grains, and beans. For example, you can eat a large volume of celery or carrots without taking in many calories.
  • Eat less "energy dense foods." Energy dense foods are high in fats and simple sugars. They generally have a high calorie value in a small amount of food. The United States government currently recommends that a healthy diet should have less than 30% fat. Fat contains twice as many calories per unit weight than protein or carbohydrates. Examples of high-energy dense foods include red meat, egg yolks, fried foods, high fat/sugar fast foods, sweets, pastries, butter, and high-fat salad dressings. Also cut down on foods that provide calories but very little nutrition, such as alcohol, non-diet soft drinks, and many packaged high-calorie snack foods.
  • About 55% of calories in the diet should be from complex carbohydrates. Eat more complex carbohydrates such as brown rice, whole-grain bread, fruits, and vegetables. Avoid simple carbohydrates such as table sugars, sweets, doughnuts, cakes, and muffins. Cut down on non-diet soft drinks, these sugary soft drinks are loaded with simple carbohydrates and calories. Simple carbohydrates cause excessive insulin release by the pancreas, and insulin promotes growth of fat tissue.
  • Educate yourself in reading food labels and estimating calories and serving sizes.
  • Consult a doctor before starting any dietary changes. You doctor or a nutritionist should prescribe the amount of daily calories in your diet.

REFERENCES:

National Institutes of Health (NIH); "Classification of Overweight and Obesity by BMI, Waist Circumference, and Associated Disease Risks." "Body Mass Index Table."

Manson JE, Colditz GA, Stampfer MJ, Willett WC, Rosner B, Monson RR, Speizer FE, Hennekens CH.; "A prospective study of obesity and risk of coronary heart disease in women." N Engl J Med. 1990 Mar 29;322(13):882-9.

W. B. Droyvold, T. I. Lund Nilsen, S. Lydersen, K. Midthjel, P. M. Nilsson, J. Nilsson, J. Holmen; "Weight change and mortality: the Nord-Trondelag Health Study." Journal of Internal Medicine. Volume 257 Issue 4, Pages 338 - 345

National Center for Health Statistics; "National Health and Nutrition Examination Survey." http://www.cdc.gov/nchs/nhanes.htm.

World Health Organization; "Global Database on Body Mass Index."

Life Measurements, Inc. (www.bodpod.com)

United States National Library of Medicine, National Institutes of Health; "Bioelectric Impedance Analysis in Body Composition Measurement."

Lars Sjöström, M.D., Ph.D., Anna-Karin Lindroos, Ph.D., Markku Peltonen, Ph.D., Jarl Torgerson, M.D., Ph.D., Claude Bouchard, Ph.D., Björn Carlsson, M.D., Ph.D., Sven Dahlgren, M.D., Ph.D., Bo Larsson, M.D., Ph.D., Kristina Narbro, Ph.D., Carl David Sjöström, M.D., Ph.D., Marianne Sullivan, Ph.D., Hans Wedel, Ph.D.. "Lifestyle, Diabetes, and Cardiovascular Risk Factors 10 Years after Bariatric Surgery." New England Journal of Medicine. Volume 351:2683-2693, December 23, 2004.

U.S.  Department of Health and Human Services, U.S. Department of Agriculture; "Dietary Guidelines for Americans."

Medically Reviewed by a Doctor on 12/9/2015