Question

what is the relationship between cola(pepsi, come) and renal stones?

Answer 1

Cola and renal stones actually does not have a cause effect relationship.However the high amount of sodium and phosphoric acid increases the risk of renal stones.Phosphoric acid increases acidity levels in the kidney tract, and this makes urine too acidic. Kidney stones form quickly in such conditions. The diuretic property in cola increases the concentration of salt in urine and promotes the formation of kidney stones.But the PEPSICO company claims that12-ounce can of Pepsi contains just over 50 mg of phosphorus where a cup of milk has over 250 mg of it. For perspective, the Reference Daily Intake for phosphorus set by the U.S. Food & Drug Administration (FDA) is 1000 mg per day.

The common belief that cola can cause kidney stones come from a study of 1,009 males randomized to either refraining from or continuing soft drinks over three years by Shushter and colleagues. In their study, those who refrained were 6.4% less likely to form another stone than those who continued their soda intake. Additionally, they observed that those who refrained from sodas acidified by phosphoric acid as opposed to sodas acidified with citric acid had a more pronounced 15% lower likelihood of forming another stone (Shuster et al, J Clin Epidemiol, 1992). Phosphoric acid is most commonly used in colas (such as Coca Cola) while citric acid is most commonly used in fruit flavored sodas (such as Sprite). Based on this study, avoidance of cola drinks was recommended by some physicians as a way to avoid stones.

In contrast to this, in study of 45,289 men, intake of 21 different types of beverages and the development of stones was determined over six years. In contrast to the prior study, the authors found that cola intake did not increase stone risk when all factors were considered. They concluded that if a person’s diet was otherwise kept the same, the addition of cola would not increase the risk of stones (Curhan et al, Am Journal Epid, 1996).

So the risk of forming renal stones remains questionable.Even if it is true, this risk applies to only phosphoric acid containing sodas, found mostly in dark colored sodas.