Drinking soda or other carbonated beverages each day may be a recipe for high blood pressure, reduced kidney function and kidney stones. This setup for kidney disease happens through a number of actions that take place when you consume just two carbonated beverages a day for a long period of time. You may think sugar-free diet soda may shield you from these adverse health effects, but you'd be wrong. Be it a cola, non-cola, diet soda or other sugar-sweetened carbonated beverage, carbonated beverages can increase your risk of serious health issues.
Carbonation and Kidney Stones
Soda, especially colas, contains high levels of phosphoric acid, which is closely linked with the development of kidney stones and other renal problems. A seminal study published in 2007 in the journal "Epidemiology" reckoned that drinking two or more colas per day was associated with increased risk of chronic kidney disease. The two-fold risk was there whether the soda contained common sugars or artificial sugars. Phosphoric acid gives food a tangy taste and beverages the acidic taste you've come to associate with soda. Phosphoric acid also has preservation qualities and acts as a mold deterrent. The acid, if consume regularly, can tax kidneys as they do their job of filtering out waste material.
Sugar, Hypertension and Chronic Kidney Disease
Uncolas, to borrow from popular vernacular, aren't immune from affecting the health of your kidneys, either. That is, carbonated beverages that aren't colas can also cause damage. The sugars in them, particularly fructose in the form of high-fructose corn syrup, can have deleterious effects on your kidneys. In 2007, a group of kidney specialists reporting in the "Journal of the American Society of Nephrology" said excessive consumption of fructose-containing beverages was a risk factor for kidney disease, marked by high blood pressure, as well as inflammation and damage to the kidneys. Although most of the fructose in soda is taken up by your liver, up to 30 percent of it goes through your kidneys, which can cause an increase in levels of uric acid, a waste product created as the kidneys break down food. That action, the researchers said, is a major mechanism through which fructose-sweetened beverages cause cardiorenal disease. They called it an environmental toxin and said people with kidney problems should be put under restrictions against fructose-containing food and beverages.
The Trouble with Sugar-Free
You may think at this point that sugar-free, diet sodas are your only option. Not so, says the National Kidney Foundation. Reviewing the literature on the subject, the foundation reported that drinking sugar-free colas and other carbonated beverages still have problematic health repercussions. Sugar-free carbonated beverages can result in diminished kidney function. Specifically, your kidney's filtration rate may drop at an accelerated pace when you consume two or more diet sodas each day. This rate is an important indicator of your kidney's functioning status. In one reviewed study, the foundation said women who drank two diet sodas each day had a 30 percent greater reduction in kidney function over 20 years than women who didn't drink diet soda.
What You Should Do
A significant portion of Americans' calories come from sodas and other soft drinks. The Dietary Guidelines for Americans 2010 recommends that all American consume fewer sodas and sugar-sweetened soft drinks or eliminate them altogether. If you or a close relative has a kidney-related health issues, talk to your doctor or dietitian about alternative beverages that can fit into your diet.
- National Public Radio: Diet Sodas May Hurt Kidneys; Scott Hensley; Nov. 3, 2009
- New York Times: The Claim: Too Much Cola Can Cause Kidney Problems; Anahad O'Connor; Jan. 22, 2008
- National Kidney Foundation: Say No to That Diet Soda?
- "Epidemiology"; Carbonated Beverages and Chronic Kidney Disease; Tina M. Saldana; July 2007
- "Journal of the American Society of Nephrology"; The Effect of Fructose on Renal Biology and Disease; Richard J. Johnson et al.; December 2010
- "American Journal of Clinical Nutrition"; Potential Role Of Sugar (Fructose) in the Epidemic Of Hypertension, Obesity and the Metabolic Syndrome, Diabetes, Kidney Disease, and Cardiovascular Disease; Richard J. Johnson et al.; October 2007
- Bastyr Center for Natural Health: Cut Down on Cola for Kidney Health; Aug. 23, 2007
- Beloit College: Two Colas a Day May Shorten Your Lifespan; Adam Whiteley