Sunday, May 25, 2008

High-Protein Diets


AHA Recommendation

The American Heart Association doesn't recommend high-protein diets for weight loss. Some of these diets restrict healthful foods that provide essential nutrients and don't provide the variety of foods needed to adequately meet nutritional needs. People who stay on these diets very long may not get enough vitamins and minerals and face other potential health risks.

Background

Many Americans follow popular diets, such as the Atkins, Zone, Protein Power, Sugar Busters and Stillman diets. Most of these diets aren't balanced in terms of the essential nutrients our bodies need. Some are high protein and emphasize foods like meat, eggs and cheese, which are rich in protein and saturated fat. Some restrict important carbohydrates such as cereals, grains, fruits, vegetables and low-fat dairy products. If followed for a long time, they can result in potential health problems. And while they may result in quick weight loss, more research is needed on their effectiveness for long-term weight loss.
These diets can cause a quick drop in weight because eliminating carbohydrates causes a loss of body fluids. Lowering carbohydrate intake also prevents the body from completely burning fat. In the diets that are also high in protein, substances called ketones are formed and released into the bloodstream, a condition called ketosis. It makes dieting easier because it lowers appetite and may cause nausea.

But these diets have other effects besides inducing quick weight loss.

Most Americans already eat more protein than their bodies need. And eating too much protein can increase health risks. High-protein animal foods are usually also high in saturated fat. Eating large amounts of high-fat foods for a sustained period raises the risk of coronary heart disease, diabetes, stroke and several types of cancer. People who can't use excess protein effectively may be at higher risk of kidney and liver disorders, and osteoporosis.
That's why the American Heart Association guidelines urge adults who are trying to lose weight and keep it off to eat no more than 35 percent of total daily calories from fat and less than 7 percent of total daily calories from saturated fat and less than 1 percent of total daily calories from trans fat. On most high-protein diets, meeting these goals isn't possible.
Some high-protein diets de-emphasize high-carbohydrate, high-fiber plant foods. These foods help lower cholesterol when eaten as part of a nutritionally balanced diet. Reducing consumption of these foods usually means other, higher-fat foods are eaten instead. This raises cholesterol levels even more and increases cardiovascular risk.
High-protein diets don't provide some essential vitamins, minerals, fiber and other nutritional elements. A high-carbohydrate diet that includes fruits, vegetables, nonfat dairy products and whole grains also has been shown to reduce blood pressure. Thus, limiting these foods may raise blood pressure by reducing the intake of calcium, potassium and magnesium while simultaneously increasing sodium intake.

What's the best way to lose weight?

A healthy diet that includes a variety of foods and is rich in fresh fruits and vegetables along with regular physical activity can help most people manage and maintain weight loss for both cardiovascular health and appearance. The American Heart Association urges people to take a safe and proven route to losing and maintaining weight. By paying attention to portion size and calories and following our guidelines, you can enjoy healthy, nutritionally balanced weight loss for a lifetime of good health.