Consuming two or more servings of sugary drinks a day may increase the risk of dying from obesity-related cancer, a new study has found.
An analysis of data from nearly one million Americans followed for nearly 30 years reveals that people who drank sugary drinks had a 5% increased risk of dying from obesity-related cancer compared to people who did not consume sugary drinks.
According to the report published in Cancer Epidemiology, those who consumed two sugary drinks a day also had a 9% increased risk of dying from colorectal cancer and a 17% increased risk of dying from kidney cancer compared to people who did not drink sugary drinks. , Biomarkers and Prevention.
“This study provides more evidence to support recommendations to reduce sugary drinks,” said the study’s first author, Marji McCullough, senior scientific director of epidemiological research at the American Cancer Society in Atlanta. “When we put BMI in the model, the 5% increase was no longer statistically significant, suggesting, at least in part, that this finding is mediated by excess weight.”
As for the increased risk of dying from colon and kidney cancer, which remained statistically significant even after controlling for BMI, “we don’t know exactly why,” McCullough said.
The study also found that consuming a similar amount of artificially sweetened beverages was associated with an 11% increased risk of pancreatic cancer, even when BMI was taken into account. “It was a new discovery,” McCullough said. “But it’s the only study that found a higher risk of pancreatic cancer and it should be replicated in follow-up studies.”
It’s possible that the increased risk in those who consume artificially sweetened beverages could be explained by other factors, McCullough said, such as diabetes. “Diabetes is a risk factor for pancreatic cancer and people with diabetes drink more artificially sweetened beverages.”
To take a closer look at the impact of sugary drinks on cancer mortality risk, McCullough and his colleagues turned to a dataset collected by the American Cancer Society, which in 1982 enrolled 1,184,284 men and women. aged 28 and over in the Cancer Prevention Study II (CPS-II).
For their analysis, the researchers focused on the 934,777 CPS-II participants who did not have cancer or diabetes at baseline and for whom complete data existed. The researchers excluded male participants over the age of 90 and women over the age of 95 when they enrolled in the study.
During the 27.7 years of follow-up, 135,093 of the participants died of cancer, representing 25.9% of all deaths in the group.
“Sugar is everywhere in our diets,” said Dr. David Heber, professor of medicine and public health at the University of California, Los Angeles and founding director of the UCLA Center for Human Nutrition. “That’s because food manufacturers know that sugar sells products everywhere from ketchup to hamburger buns.”
And 33% of the sugar consumed by Americans comes from sugary drinks, said Heber, who was not involved in the new research. These drinks can have a huge impact, he added.
“An 8-ounce cola has 37g of sugar, and the blood can only carry a limited amount of sugar, about 5g,” Heber said. “Excess sugar is transported to the liver where it is turned into fat or is transported to the muscles where it is burned during exercise. Fat is an inflammatory organ that may help promote cancers in men and women. women.
Heber suspects the link between sugary drinks and colon cancer may have something to do with the impact of sugar on the microbiome. As for the kidneys, when they filter out a lot of sugar, it can have a detrimental effect, Heber said.
Dr. Emanuela Taioli suspects that the observed association between artificially sweetened drinks and pancreatic cancer may be linked to the fact that many people switch to these drinks after already being obese.
“So it may be an opposite effect,” said Taioli, director of the Institute for Translational Epidemiology and associate director of population sciences at the Tisch Cancer Institute of Mount Sinai Health System. “It’s a much more complicated story when you look at artificially sweetened beverages.”
Taioli is concerned for all the children who have been exposed at school to sugary drinks from vending machines. For many, this may be where the taste for sugary drinks begins, she said.
Americans’ diets have changed significantly since CPS-II began, said Linda Van Horn, professor of preventive medicine and division chief of nutrition at Northwestern University’s Feinberg School of Medicine.
“I think, frankly, the most important thing identified here, which has been pointed out before, is the unfavorable relationship between any type of cancer and the development of obesity,” Van Horn said. “Keep in mind that the vast majority of us are either overweight or obese.”
Ultimately, the findings underscore the importance of primary obesity prevention, Van Horn said. “I tend to focus on maternal-fetal medicine and pediatrics,” she added. “We have the opportunity to start with young people when it comes to primary prevention. We know that once a child begins a trajectory of weight gain, they are at the greatest risk of becoming overweight or obese.