Maintaining a healthy weight is important for everyone, especially for kidney patients who are at higher risk for heart disease. However, not all diets are created equal. While the Atkins Diet may be appropriate for people with healthy kidneys, it can cause serious problems for people who have kidney disease.
Definitions
In addition to describing advanced kidney disease in which dialysis or transplant is needed to sustain life, the term "kidney failure" also describes early stages of the disease in which the patient experiences nothing more than edema and hypertension. Sometimes "kidney failure" is used interchangeably with the term "renal insufficiency," when describing these early stages of disease. The Atkins diet is a high-protein diet used for weight loss. Dieters consume extra protein and fat, while minimizing their carbohydrate intake.
Proteinuria
Patients in the early stages of kidney disease often have high urine protein, also known as proteinuria. The filters of the kidney are called glomeruli. Healthy glomeruli keep proteins in the blood and prevent them from getting into the urine. This is not the case with inflamed glomerular tissue, which allows proteins to pass into the urine. Independent of the underlying disease, high urine protein accelerates the progression of kidney disease because proteins are large complex molecules. They cause unneeded wear and tear on fragile glomeruli, which are nothing more than fragile blood vessels. High protein diets only make matters worse because they increase the amount of protein that reaches the urine.
Low-Protein Diet
The National Kidney Foundation recommends that patients with stage three kidney disease limit daily dietary protein to 0.75 g per kilogram body weight, and that patients which stage 4 kidney disease limit daily protein intake to 0.6 g per kilogram body weight. Stage 3 disease includes patients who have 30 to 59 percent renal function. Stage 4 disease includes those patients with 15 to 29 percent function. The rationale for these recommendations is that lowering dietary intake will lower the level of protein in the patient's urine. The National Kidney Foundation specifically mentions the Atkins diet, saying that it is inconsistent with these recommendations.
Alternatives
Instead of the Atkins Diet, kidney patients trying to lose weight should consult their nephrologists and renal dietitians for advice, especially if they have to limit the amount of phosphorus and potassium in their diets. Increasing exercise is an excellent strategy. Aerobic exercise is excellent because cardiovascular disease is the leading cause of death among kidney patients. Exercise that builds muscle is also advisable because it may counteract the muscle-wasting that often occurs with advanced disease.
References
- National Kidney Foundation: K/DOQI Clinical Practice Guidelines on Hypertension and Antihypertensive Agents in Chronic Kidney Disease
- National Kidney Foundation: KDOQI Clinical Practice Guidelines for Chronic Kidney Disease: Evaluation, Classification, and Stratification
- MedlinePlus: Kidney Failure
- Foundation for IgA Nephropathy: Chronic Renal Insufficiency
- National Institute of Diabetes and Digestive and Kidney Disease: Proteinuria
