Protein Is the Darling of the Dieting Set -- For Now
WebMD News Archive
Nov. 25, 1999 (Atlanta) -- Here's some food for thought for people planning on targeting the turkey while skipping the stuffing in the hopes of losing weight this Thanksgiving: A majority of experts warn against so-called protein diets.
Although these types of diets have been around for decades, they seem to be enjoying a renaissance in popularity lately. Consider the number of diets out there -- the Atkins diet, the Zone, and the so-called "Mayo Clinic" diet -- to name a few. While the diets vary widely in what is permissible to eat, their common denominator is an emphasis on protein (meat, fish, poultry, eggs, tofu, and nuts) and a downplaying -- if not an outright elimination -- of carbohydrates (breads, cereals, rice, pasta, fruits, and vegetables).
"They are quick fixes; they are your basic magic bullet," registered dietician Kathleen Zelman, a spokesperson for the American Dietetic Association, tells WebMD. "The reason they have been around for so long is that they indeed work, in the short term, to produce weight loss. The problem is the weight loss is primarily a fluid loss [which] occurs in the first couple of weeks, [giving] people the illusion that this is a very effective diet."
Effective? Maybe. But sustainable? Maybe not. When a person embarks on a high-protein diet, their body goes into what is called ketosis. "[Ketosis] is an altered type of mechanism for your body to get fuel," explains Zelman. "Your body's preferred form of fuel is glucose; glucose is generally obtained from carbohydrates. [Without carbohydrates] your body goes into an altered metabolism and it uses protein and fat. Ketone bodies are a by-product of protein metabolism."
Zelman says fat is mobilized in this altered metabolism, but that ketosis over the long term can be dangerous. "Ketosis is a bizarre and unnatural state -- it gives you funny breath and some people have physiological problems when they are in ketosis."
There are numerous other reasons people shouldn't stay on a high-protein diet for long periods of time. "It defies all health authorities' recommendations. ... A diet that is high in protein ... is hard to keep low in fat, although there might be some that do," says Zelman, noting that meat, bacon, cheese, and cream -- things that are high in saturated fat -- are staples in some of these diets.
"All the health authorities have convincingly recommended to the nation at large that diets high in saturated fat are linked with [heart] disease and elevated cholesterol levels. So in that respect the fat is dangerous. It also lacks fiber, so it could be disconcerting to the [intestinal] tract. Also, the high protein content is taxing on the kidney, so if you have predisposition to kidney disease that could further escalate things," Zelman tells WebMD.