In January 1991, Dr. Kathleen Zeller, associate professor of internal medicine at UT Southwestern, reported the results of a study showing that insulin-dependant diabetics can slow their loss of kidney function by eating less protein. Her research was published in The new England Journal of Medicine. It's estimated that about half of all people with insulin-dependant diabetes, also called juvenile-onset diabetes, eventually will suffer kidney failure, which necessitates either repeated dialysis treatment or transplant surgery.
Dr. Zeller said research in rats showed that high blood pressure occurs within the kidney when it is damaged by disease. The researchers succeeded in reducing the damage by reducing the rodents' protein intake and, thus, lowering their blood pressure. Based on the animal research, Dr. Zeller and her colleagues decided to test this premise in humans. Typically, Americans eat 1 to 1.5 grams of protein per day for every 2.2 pounds (or 1 kilogram) they weigh. Dr. Zeller and her colleagues selected 20 subjects whose kidneys had already begun to fail and put the patients on a diet containing approximately 0.7 grams of protein for every kilogram they weighed (half of their normal protein intake). Fifteen other patients continued to eat their regular diet of 1.1 grams of protein for every kilogram of weight. In the end, the rate of progression of kidney failure was significantly lower in the lower-protein group.
An egg or 1 ounce of meat contains about 7 grams of protein. A glass of milk contains 8 grams, a slice of bread contains 2 grams. Other food items that contain significant amounts of protein include cheese, fish and poultry. Because of the danger of malnutrition, Dr. Zeller emphasizes that patients should consult their physicians before altering their diets. Persons with no history of diabetes should not reduce their intake of protein below the recommended daily allowance.
