FOR RELEASE: MARCH 2004

 

IMPORTANT THINGS TO KNOW ABOUT HIGH PROTEIN, LOW CARBOHYDRATE DIETS

 

STILLWATER---High protein, low carbohydrate diets are currently very popular, but this weight loss approach is not new. In fact, high protein, low carbohydrate diets have been around since the 1970’s. The high protein, low carbohydrate diet is popular because there is an initial weight loss that attracts people. High protein, low carbohydrate diets work by promoting ketosis. Carbohydrate is an important source of energy for muscles and the only source of energy used by the brain and the nervous system. In the first few days of a very low carbohydrate diet, water is released from the tissues. The body uses the little bit of carbohydrate it has stored as glycogen. Glycogen is stored bound to water in the body, so water is excreted as the glycogen stores are reduced and people can lose 2-4 pounds or more of body water in just a few days. Unfortunately, a body deprived of carbohydrate may respond in ways that are not desirable. After, glycogen stores are depleted the body will turn to stored fat and protein for energy. When stored fat is broken down too rapidly, a condition called ketosis occurs. Advocates of high protein diets promote the advantages of ketosis to accelerate weight loss. However ketosis is an abnormal body process that occurs due to lack of carbohydrate. Ketosis can lower the appetite and cause fatigue, constipation, nausea, vomiting and dehydration. Dehydration can make you feel tired, weak, dizzy, and experience headaches. We need to eat at least 100 grams of carbohydrate each day to prevent ketosis. 

Unfortunately, the initial weight loss from a high protein, low carbohydrate diet is usually due to water loss, not loss of body fat. The continued weight loss observed with high protein, low carbohydrate diets may simply be because people are consuming fewer calories, something that often happens when people drastically change what they eat. High protein, low carbohydrate diets limit such a large number of foods that most people following them consume fewer calories. In the long run however, the results don’t last. For many people the weight comes back when they return to their normal eating pattern.

In addition, high protein, low carbohydrate diets are not considered health promoting for the long run. They tend to be low in vitamins, minerals, dietary fiber and photochemical (beneficial components of plant foods). Diets high in fruits, vegetables, whole grains, beans and legumes and low in fat are all promoted to lower the risk of heart disease, high blood pressure and certain types of cancer including breast and colon. There are health risks to high protein, low carbohydrate diets in the long run. These diets can be high in fat and saturated fats, which can increase the risk of heart disease. In addition, high protein intake can over time increase the risk of kidney problems and osteoporosis. When protein is broken down in the body to be used for energy, the by-products are processed by the kidneys. High protein diets are not recommended for people with diabetes or reduced kidney function. High intakes of animal protein can increase calcium loss from the body.