Your kidneys filter your blood and release toxic substances from digested foods into your urine for elimination. Some foods, especially when eaten in excess, produce waste products that can damage your kidney filtration capabilities, and your health. Excess consumption of protein-containing foods, such as red meat, produces by-products that stress kidney function. Knowing how these foods might affect your kidneys can help to reduce adverse health effects.
Red meat eaten on a daily basis provides the main form of protein for many diets. When your body breaks down proteins in your diet, it releases a substance called urea into your bloodstream. Your kidneys filter urea from your blood and release it via your urine. If you have kidney disease, urea can build up in your body and cause adverse side effects. Eating red meat should not affect healthy kidneys. However, with kidney disease, eating excess amounts of red meat can impact your health.
Animal proteins, such as red meats, contain purines that your body metabolizes into uric acid. Eating excess animal proteins increases uric acid levels in your blood and can lead to kidney stone development, according to Harvard Medical School. Saturated fats and cholesterol found in red meats increase your risk for renal artery disease -- hardening of the arteries -- and can block the arteries leading to your kidneys, warns Stony Brook Heart Institute.
A study published in the "American Journal of Clinical Nutrition" followed 17 participants who had both diabetes and kidney damage. Researchers separated the study participants into three groups. The first group ate a diet that included red meat; the second group ate a diet that involved eating only dark chicken meat; and the third group ate a low-protein vegetarian diet. Participants followed their recommended diets for four weeks, resumed their typical diets for the next four weeks and then returned to the recommended diet for four additional weeks. When the study concluded, the researchers found those whose diets did not include red meat had less albumin -- a waste product that indicates kidney damage -- than those who did eat red meat. The study concluded that red meat affected kidney function more than other protein sources.
If you have impaired kidney function, do not eliminate protein from your diet. Protein serves as an energy source and helps your body maintain muscle mass. However, your physician may recommend decreasing your protein intake to compensate for any possible kidney damage. Because red meat tends to contain significant amounts of protein per serving, you may need to limit your portion sizes and the frequency at which you eat red meat. After establishing appropriate limits with your physician, you can determine the amount of red meat you should eat.
Excess waste products from protein breakdown can cause symptoms in the body such as fatigue, weakness and nausea. If you experience these symptoms after eating red meat, you may have increased susceptibility to red meat's effects or your kidneys may have difficulty breaking down protein.
- University of Maryland Medical Center: Kidneys/Kidney Disease
- Washington University: Maintaining Body Chemistry: Dialysis in the Kidneys
- National Kidney and Urologic Diseases Information Clearinghouse: Nutrition for Later Chronic Kidney Disease in Adults
- Bastyr Center for Natural Health: Cutting Red Meat Spares Diabetic Kidneys
- Harvard Health Publications, Harvard Medica School: 5 Steps for Preventing Kidney Stones
- Stony Brook Heart Institute: Renal Artery Disease
- National Kidney Foundation: Your Kidneys and Your Heart
- University of Michigan Health System: Renal Artery Disease (Adult)
- Rush Medical Center: Considering Cutting Carbohydrates from Your Diet and Packing on the Protein? Read This First.