Breast cancer patients who drink non-diet soda have higher death risk

"Non-diet sodas are the highest contributors of sugar and extra calories to the diet, but they do not bring anything else that is nutritionally beneficial," says Nadia Koyratty. "On the other hand, teas, coffees, and 100% fruit juices, unless sugars are added, are healthier beverage options because they do add to the nutritive value through antioxidants and vitamins." (Credit: Getty Images)

Breast cancer patients who drink sugar-sweetened soda regularly are at increased risk for death from any cause and from breast cancer in particular, a new study suggests.

Compared to women who never or rarely drank non-diet soda, those who reported drinking non-diet soda five or more times per week had a 62% higher likelihood of dying from any cause, and were 85% more likely to die from breast cancer specifically.

Research on soda and breast cancer is fairly new, says study first author Nadia Koyratty, a PhD candidate in the epidemiology and environmental health department in the School of Public Health and Health Professions at the University at Buffalo.

Because breast cancer is so common, recommendations regarding lifestyle choices to breast cancer survivors are of considerable importance. And, despite the negative health outcomes associated with drinking soda, such as weight gain, Type 2 diabetes, and cardiovascular disease, many people continue to drink sugar-sweetened sodas.

Thus far, there have been only a few observational studies examining the association between sugar-sweetened beverages and cancer mortality.

“This study is one of the few that looks at the prognosis of women with breast cancer with respect to non-diet soda consumption,” Koyratty says.

For the study, published in Cancer Epidemiology, Biomarkers & Prevention, researchers assessed the relationship between sugar-sweetened soda and both all-cause and breast cancer mortality among 927 women who had been diagnosed with breast cancer, aged 35 to 79. Participants were enrolled in the Western New York Exposures and Breast Cancer (WEB) Study, and followed for a median of nearly 19 years.

The study used a food frequency questionnaire to assess participants’ food and beverage intake in the 12 to 24 months prior to diagnosis. Of the more than 900 women diagnosed with breast cancer, 41% had died by the end of the follow-up period. Among the participants who had died, there was a higher percentage of women who reported high frequency of sugar-sweetened soda consumption compared to the women who were still living.

The associations did not change when researchers included diet soda consumption as a variable.

Why the focus on non-diet soda?

“Non-diet sodas are the highest contributors of sugar and extra calories to the diet, but they do not bring anything else that is nutritionally beneficial,” Koyratty says. “On the other hand, teas, coffees, and 100% fruit juices, unless sugars are added, are healthier beverage options because they do add to the nutritive value through antioxidants and vitamins.”

Sugar-sweetened sodas contain large quantities of sucrose and fructose, which give them the highest glycemic load compared to other foods or beverages. These higher concentrations of glucose and insulin may lead to conditions that have been associated with higher risk of breast cancer, the researchers note.

“There are more than 3.5 million breast cancer survivors alive in the US today. We need to better understand the factors that affect their health,” says senior author Jo L. Freudenheim, professor in the epidemiology and environmental health department.

“While we need more studies to confirm our findings, this study provides evidence that diet may impact longevity of women after breast cancer,” Freudenheim says.

Additional coauthors are from Roswell Park Comprehensive Cancer Center, Vin University, and the University at Buffalo. The Army Medical Research and Material Command, National Cancer Institute, and the National Institute on Alcohol Abuse and Alcoholism funded the work.

Source: University at Buffalo