Answer. You did not mention your weight, since dietary protein restriction for patients with chronic kidney disease (CKD) is usually calculated in terms of grams of protein per kilogram (2.2 pounds) of body weight. Assuming your weight is around 60 kilograms (kg), then it sounds like you were prescribed a diet with 0.8 grams protein per kg body weight and your dietitian is recommending a diet with 1.0 grams protein per kg body weight. Both of these diets are appropriate, since the recommended range for daily dietary protein in patients with CKD is 0.8-1.0 grams per kg body weight. There are some nephrologists who recommend a dietary protein intake of less than 0.8 grams per kg body weight. This is based on a review of the medical literature on this subject, which revealed that such a diet reduced the rate of decline in kidney function in patients with CKD. The fact that such a diet may delay the need for dialysis is because many of the symptoms of kidney failure, are due to the accumulation of products from the breakdown of dietary protein. However, the largest clinical study to address this issue, the Modification of Diet in Renal Disease (MDRD), failed to demonstrate a beneficial result from moderate or severe dietary protein restriction in patients with various levels of CKD due to a variety of causes, such as high blood pressure.

Furthermore, the higher cost, inconvenience, and poor taste of low protein diets hinders patient adherence to these diets and increases the risk of protein malnutrition if the patient's food intake is not closely supervised by a renal dietitian. Protein malnutrition, which may be compounded by the poor appetite experienced by many patients as they approach the need for dialysis, is a common problem in patients with advanced CKD. Protein malnutrition is associated with an increased risk of death during the first year on dialysis. As a result, most nephrologists are not recommending dietary protein restriction, but rather recommending against dietary protein excess, since high protein intake does accelerate the rate of decline in kidney function. This compromise position is a daily protein intake of 0.8-1.0 grams per kg body weight under the supervision of a renal dietitian. If your weight is 60 kg (132 pounds), then a daily protein intake of 60 grams would keep you within this recommended range to protect your kidneys. This would also give you a little more variety in terms of you food choices, making it more likely you will stick to the diet. Your nephrologist may feel that the 47 gram protein diet will protect your kidneys a little more than the 60 gram protein diet, and this is also a reasonable approach as long as your nephrologist follows your serum albumin level to assure that you are not developing protein malnutrition.

Answer provided by Jay Wish, MD, Professor of Medicine in the Division of Nephrology at the University Hospital in Cleveland, Ohio. Dr. Wish is also a member of the AAKP Medical Advisory Board. 

The American Association of Kidney Patients presents Ask the Doctor, an opportunity for readers to submit kidney related health questions to healthcare professionals who specialize in an area of concern. The answers are not to be construed as a diagnosis and therefore, alterations in current healthcare should not occur until the patient’s physician is consulted.

This article originally appeared in the June/July 2003 issue of Kidney Beginnings: The Magazine, Vol. 2, No. 2.

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