You may think diet sodas offer advantages over sugar-sweetened beverages. While diet sodas have virtually no calories, they have disadvantages that may make you reconsider consuming them. Over time, the human body developed an effective means of controlling blood sugar. Negative effects of diet soda on kidney function may occur because of the chemical makeup of artificial sweeteners used in diet sodas. Aspartame, for example, is not sugar but a chemical derived from protein. Diabetics may drink diet soda to control their sugar intake, but it may be increasing their risk of complications.
How the Kidneys Work
The role of the kidneys is to filter blood and remove toxins while retaining the necessary substances. The kidneys also regulate sodium and potassium concentration in the blood. Kidneys contain millions of structures called nephrons. Within each nephron is a cluster of capillaries called the glomerulus that filters the blood for toxins. The concern is that diet soda may interfere with your kidneys' ability to manage wastes, especially in individuals with an increased risk of kidney disease such as diabetics.
Diabetes and Kidney Disease
Diabetics with risk factors such as high blood pressure and uncontrolled blood sugar have a greater chance than others of developing kidney disease. Diagnosis is confirmed by the presence of proteins in the urine. Research findings presented by Harvard Medical School researchers, published in the January 22, 2010, issue of "Renal and Urology News," showed that people consuming two or more servings of artificially sweetened soft drinks were more than twice as likely to experience a 30 percent decrease in glomerular filtration rate. If you consume diet soda to control your carb intake, you may increase your risk of kidney disease.
Complications
The potential for impaired kidney function from drinking diet soda increases if you have other risk factors such as consumption of a diet high in sodium. Because the kidneys regulate sodium, the combination of a high-sodium diet and regular diet soda consumption may increase your risk. The Harvard Medical School study also showed that diabetics consuming a high-sodium diet had a 52 percent increased risk of a 30 percent or greater reduction in glomerular filtration rate. The researchers recommended limiting consumption of diet sodas to two or less a day in addition to following a low-sodium diet to reduce the risk of kidney function decline.
Weight Gain
Diet soda may indirectly affect kidney function by causing you to gain weight. Being overweight increases your risk of diabetes and kidney disease. Experiments on rats performed by researchers at Purdue University in Indiana, published in the February 2008 issue of "Behavioral Neuroscience," showed that foods with artificial sweeteners hampered the body's natural ability to respond with a feeling of satiation. The researchers explained that the body has evolved to expect a higher caloric intake once taste receptors detect sweetness in food. The body is expecting calories and not getting them, which results in overeating. These findings may suggest you should limit your consumption of diet soda.
References
- Aspartame Information Center: Aspartame Fact Sheet
- National Kidney and Urologic Diseases Information Clearinghouse; The Kidneys and How They Work; September 9, 2010
- American Diabetes Association: Kidney Disease (Nephropathy)
- "Renal and Urology News"; Diet Soda, Salt May Harm Kidneys; Jody A. Charnow; January 22, 2010
- Mayo Clinic; Diabetes: Risk Factors; March 9, 2011
- "Behavioral Neuroscience"; A Role for Sweet Taste: Calorie Predictive Relations in Energy Regulation by Rats; S. Swithers and T. Davidson; February 2008
