FROM THE EDITORS
Understanding the link between diet and kidney disease
By John Graves, M.D.
Consultant, Division of Nephrology and Hypertension, Mayo Clinic
Mayo Clinic Health Letter in last month's cover story brought you important information on "Ways to save your kidneys."
A section of that article "Eating with kidney health in mind" explained that while it is important to eat enough protein to meet your body's needs, many people consume more protein than is actually needed.
Because this information is so important to people who are dealing with chronic kidney disease, it's good to expand on the connection between diet and kidney function decline. This is especially important since it has been my experience that misconceptions remain in this area, not only among patients, but among clinicians as well.
The article "Diagnosis and Management of Chronic Kidney Disease" — which I authored for the September 2008 issue of Mayo Clinic Proceedings — included this observation: While a low-protein diet has never been shown to be beneficial in reducing the rate of kidney function decline in humans, it is often still recommended.
The truth is that a low-protein diet is counterintuitive as a means of slowing the rate of kidney filtration rate decline: When patients reduce their protein intake, they tend to replace those protein calories with fat and glucose calories. These replacement calories can actually accelerate disease development affecting the heart and blood vessels.
People who have chronic kidney disease generally do not die of renal failure. However, they do die of heart attack or stroke, often before reaching the final stages of their kidney disease. For this reason, the American Heart Association diet, which is low in fat and salt, is the preferred diet for those dealing with kidney disease.
If you have kidney disease, you may feel overwhelmed with the many major modifications in lifestyle that you are asked to make. Instead, for best results, focus your attention on the most important modifications, such as low sodium, low fat, weight loss or stopping smoking.