Drinking diet soda has been linked to an increased risk of chronic kidney disease. A recent study analyzed the diets of 15,368 people and found that the risk of developing end-stage kidney disease increased with the number of glasses of diet soda consumed per week.
Compared with those who consumed less than one glass per week, people who drank more than seven glasses of diet soda per week had nearly double the risk of developing kidney disease.
A suggested cause for the kidney damage is the high phosphorus content of soda, which may increase the acid load on the kidneys.
However, it has also been suggested that people consuming high amounts of diet soda may do so to compensate for other poor dietary and lifestyle factors that may independently contribute to the development of kidney disease.
Interestingly, studies investigating the effects of diet soda on the development of kidney stones have found mixed results.
One observational study noted that diet soda drinkers have a slightly increased risk of kidney stone development, but the risk was much smaller than the risk associated with drinking regular soda. In addition, this study has not been supported by other research.
Another study reported that the high citrate and malate content of some diet sodas may help treat kidney stones, particularly in people with low urine pH and uric acid stones. However, more research and human studies are needed.