Protein Power (cont.)
If you are very overweight, the initial phase of the diet (when carbohydrates are severely restricted) will almost certainly put you in a state of ketosis, which happens when fat breaks down to the point where ketone bodies are produced and excreted in the urine. Ketones are incompletely burned fat, say the Eades, so that any ketones "you get rid of without actually using them for energy means you are ditching unwanted fat without having to actually burn it off."
Is ketosis dangerous, as some nutritional authorities would have you believe? Not at all, attest the authors. Ketones are the natural by-product of fat breakdown, normal and important sources of energy. To facilitate getting rid of these ketones, they urge you to increase your fluid intake by as much as 50%, to at least two quarts of water-based fluids a day.
As for exercise, the authors favor resistance-training, such as weight lifting, because it stimulates the release of growth hormone more quickly than aerobic exercise. Why is this important? Because growth hormone shifts the metabolism to the preferential use of stored fat for energy.
Low-carbohydrate diets, which always mean high protein, almost universally draw a red flag from conventional nutritionists and medical experts. But since they do jump-start weight loss that you can see quickly, some say they have their place. "Fad diets are OK for a quick start," notes Bonnie Brehm, PhD, assistant professor of nutrition at the University of Cincinnati's College of Allied Health Sciences in Cincinnati, Ohio. "Some people need to see that five-pound weight loss rather than just a single pound after a week of dieting." Brehm is conducting a study comparing a high protein diet with the low-fat diet recommended by the American Heart Association.
"In the short term, the low-carb diets are effective -- we see weight loss, improvement in some metabolic functions such as blood pressure, loss of body fat, but their real hazard is that they are nutritionally poor," she says. "They are low in calcium, low in vitamins C and A, low in fiber. We don't know if taking a vitamin-mineral supplement is adequate. There are a lot of micronutrients in foods that are not in supplements, including some we don't even know about yet. We do not have any long-term studies on these alternative diets with the extreme modifications of a nutritionally balanced diet."
Susan B. Roberts, PhD, a professor of nutrition and psychiatry at Tufts University in Boston, Mass., and co-author of Feeding Your Child for Lifelong Health, does not recommend the diet because there is no good evidence that low-carbohydrate diets work any more effectively than conventional ones. Furthermore, she says, "Because they cut back on foods that have multiple health benefits, they may reduce health in the long term."
Roberts notes that the Protein Power regimen may work for many, but the reason is different from the theory put forth in the book. It simply may be the lack of variety that works to reduce overall calorie intake. "Protein Power and most other popular diet books substantially reduce the variety of foods you are allowed to eat -- and variety itself is a major promoter of overeating," she says.
As with any of the currently popular low-carbohydrate and high-protein diets, this plan yields weight loss on the short term. However, the established nutritional community warns that these eating plans can be seriously deficient in important nutrients. While this plan does offer a range of sample diets and menus, it requires a reduction in the variety of foods that one can eat, which may be difficult to sustain over the long term.
Reviewed By Charlotte E. Grayson, MD February 2004.
SOURCES: Eades, M. Protein Power, 1998, Bantam Books. Bonnie Brehm, PhD, assistant professor of nutrition, the University of Cincinnati's College of Allied Health Sciences, Cincinnati. Susan B. Roberts, PhD, professor of nutrition and psychiatry, Tufts University, Boston.
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