Does Diet Soda Cause Kidney Cancer? Bladder Cancer?

The short answer is, "No."  

Aspartame is the low-calorie, synthetic sweetener used in most diet sodas in this country and around the world.  Aspartame was approved by the US Food and Drug Administration (FDA) in 1984 and, since then, been approved in over 100 countries and world-health organizations.  The average daily intake in the US is estimated to be about 1/10th of the Acceptable Daily Intake (ADI) that would cause a toxicity.  Said differently, a normal-person would have to drink a 12-pack of cans or 4 liters of diet soda every day to exceed the ADI as set by the FDA.[1]

However, in the 1970's a number of scientific studies raised concerns of aspartame and its byproducts causing cancer in rodents.  Since then, the role of aspartame (and other synthetic saccharins) has been highly debated in the scientific and lay-literature.  A number of epidemiologic studies since 1990 have investigated the association between artificial sweeteners and malignancies, mostly in the form of large case-control and cohort studies.  Among the best-designed and executed studies, data from two longitudinal health surveys: the Nurses’ Health Study (started in 1976, and includes121,701 female registered nurses) and the Health Professionals Follow-up Study (started 1986, including 51,529 male health professionals), found a statistically significant increase in the risk of non-Hodgkin’s lymphoma and multiple myeloma (if > 1 serving of diet soda per day).[2]  The National Institute of Health—American Association of Retired Persons diet surveillance study included 473,984 individuals found no significant increase in risk of hematopoietic neoplasms or gliomas.[3]  No study has demonstrate an increased risk of urological malignancies including kidney and prostate.[4]

Interestingly, the carcinogenic effect of synthetic saccharins is species- and organ-specific.  For instance, experimental studies on rats found an increased rate of lymphomas and leukemia in females, but not in males; and hepatocellular carcinomas and alveolar/bronchiolar carcinomas in males only.[5,6]  In addition, male rats (and not females) given high doses of sodium saccharin form precipitates in the urine and has led to a literature regarding the role of aspartame and saccharins in bladder cancer.[7]  Importantly, no epidemiological study in humans has verified an association between sweeteners and bladder cancer. [8-12]

So, while a number of studies in animals demonstrate an increased risk of urological malignancies in animals, no study demonstrates an increased risk of prostate, kidney or bladder cancer in humans.  

In summary,

Aspartame is the synthetic sweetener found in most diet soft drinks around the world; it has been approved by the FDA and numerous regulatory agencies around the world.

A number of animal studies demonstrate an increased risk of cancer with long-term exposure to aspartame and other sweeteners; the risk of malignancy varies by sex and species of animal.

Human studies demonstrate an increased risk of hematogenous malignancies (lymphoma, leukemia); but no increased risk of prostate, kidney or urothelial cancers.

Your diet soda is safe.

This entry was in response to actual patients' questions and concerns raised while in our Urology Clinic.  We will routinely respond to these inquiries.  If you have a question or issue you would like addressed, do not hesitate to reach out.



[1] Marinovich M, Galli CL, Bosetti C, Gallus S, La Vecchia C.  Aspartame, low-calorie sweeteners and disease: regulatory safety and epidemiological issues.  Food Chem Toxicol. 2013 Oct;60:109-15. doi: 10.1016/j.fct.2013.07.040. Epub 2013 Jul 23.
[2] Schernhammer ES, Bertrand KA, Birmann BM, Sampson L, Willett WW, Feskanich D. 2012. Consumption of artificial sweetener- and sugar-containing soda and risk of lymphoma and leukemia in men and women. Am J Clin Nutr 96:1419–1428.
[3] Lim U, Subar AF, Mouw T, Hartge P, Morton LM, Stolzenberg-Solomon R, Campbell D, Hollenbeck AR, Schatzkin A. 2006. Consumption of aspartame-containing beverages and incidence of hematopoietic and brain malignancies. Cancer Epidemiol Biomarkers Prev 15:1654–1659.
[4] S. Gallus, L. Scotti, E. Negri, R. Talamini, S. Franceschi, M. Montella, A. Giacosa, L. Dal Maso, C. La Vecchia.  Artificial sweeteners and cancer risk in a network of case-control studies.  Ann. Oncol., 18 (2007), pp. 40–44
[5] M. Soffritti, F. Belpoggi, D. Degli Esposti, L. Lambertini, E. Tibaldi, A. Rigano.  First experimental demonstration of the multipotential carcinogenic effects of aspartame administered in the feed to Sprague-Dawley rats.  Environ. Health Perspect., 114 (2006), pp. 379–385
[6] M. Soffritti, F. Belpoggi, M. Manservigi, E. Tibaldi, M. Lauriola, L. Falcioni, L. Bua.  Aspartame administered in feed, beginning prenatally through life span, induces cancers of the liver and lung in male Swiss mice.  Am. J. Ind. Med., 53 (2010), pp. 1197–1206
[7] Capen, C.C., Dybing, E., Rice, J.M., Wilbourn, J.D., 1999. Species differences in thyroid, kidney and urinary bladder carcinogenesis. IARC Scientific Publ. No. 147. Lyon, France: International Agency for Research on Cancer.
[8] Wynder EL, Stellman SD. Artificial sweetener use and bladder cancer: a case-control study. Science1980; 207: 1214–1216. 
[9] Morrison AS, Buring JE. Artificial sweeteners and cancer of the lower urinary tract. N Engl J Med1980; 302: 537–541. 
[10] Piper JM, Matanoski GM, Tonascia J. Bladder cancer in young women. Am J Epidemiol1986; 123: 1033–1042. 
[11] Cartwright RA, Adib R, Glashan R, Gray BK. The epidemiology of bladder cancer in West Yorkshire. A preliminary report on non-occupational aetiologies. Carcinogenesis1981; 2: 343–347.
[12] Sturgeon SR, Hartge P, Silverman DT et al. Associations between bladder cancer risk factors and tumor stage and grade at diagnosis. Epidemiology1994; 5: 218–225.