POSTED: 1:30 a.m. HST, Jan 4, 2011
It is that time of the year when all the weight loss "experts" crawl out of the woodwork to promise quick fixes for extra flab. Unfortunately, few of these so-called solutions to weight problems are based on good science.
Individuals develop excess body fat for a variety of reasons. However, our bodies all function much the same when it comes to basic nutrition and weight loss. Fortunately, researchers are putting together more of the critical pieces of the nutrition and weight management puzzle.
Question: Will quick weight loss promote maintenance of a lower body weight?
Answer: Not likely. Quick weight loss is not fat loss. It is primarily loss of the body's carbohydrate storage, muscle protein breakdown and associated body water. Unfortunately, the loss of muscle protein leads to a reduced calorie requirement and a strong tendency for rapid weight regain.
If you want to lose 10 pounds, it is important to ask yourself, "Ten pounds of what?" Of course, your answer is likely to be, "Ten pounds of fat." But if you want quick weight loss, it will not be fat loss. It is not possible to lose fat rapidly. However, weight loss approaches that improve health and support the maintenance of reduced weight do focus on losing fat and consider more than just cutting calories.
Q: What foods are important for protecting muscle mass while losing body fat?
A: As calorie intake is reduced, high-protein foods become increasingly important. During low-calorie dieting, the body is forced to use more protein for its calorie needs, and this can lead to the loss of muscle. The lower the calorie intake, the more protein will be used for energy needs. Consequently, when calorie intake is low, protein needs increase.
Q: How much protein is needed during weight loss?
A: Donald K. Layman from the University of Illinois and other researchers suggest that breakfast, lunch and dinner meals each contain about 30 grams of protein. They also recommend that when calorie intake is reduced for weight loss, total protein intake for a day should be about 1.5 grams protein per kilogram of body weight (about 0.7 grams protein per pound of body weight).
This protein intake reduces muscle protein loss and promotes fat loss instead. Based on this recommendation, a 200-pound person should be consuming about 135 grams of protein per day during attempts to lose weight. This would require about 45 grams of protein at each of three meals. However, if the weight loss goal is more gradual, then the recommendation for 30 grams of protein with each meal should be adequate.
Q: What foods provide high protein?
A: The best protein food sources are not too high in the other calorie components, namely fat and carbohydrate. Also, these foods should contain protein that is readily digestible and composed of a good balance of the essential amino acids. Key foods that meet these criteria include fish, poultry, lean meats, eggs and milk products that are not high in fat. In addition, these protein foods are all good sources of the amino acid leucine, which is known to stimulate muscle protein synthesis and reduce muscle protein loss. Beans, nuts and grains can provide some protein, but the protein is of lower quality and these foods contain two to four times the calories per gram of protein as lean meat, poultry, fish or nonfat dairy products.
Joannie Dobbs, Ph.D., C.N.S., and Alan Titchenal, Ph.D., C.N.S., are nutritionists in the Department of Human Nutrition, Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii-Manoa. Dobbs also works with University Health Services.