Many have attempted to tackle the mystery behind the disease nicknamed “the silent killer.”
“When it comes to pancreatic cancer, we don’t have a clue,” said Mark Pereira, associate professor of epidemiology at the University of Minnesota. “By the time you get diagnosed, you’re basically starting to die. There’s not much at all we can do.”
Pereira recently led a study that added itself to the growing list of attempts to explain the disease’s mysterious causes. His conclusion: Soda may be to blame.
The study followed more than 60,000 middle-aged and older Chinese men and women in Singapore for 14 years, keeping track of their age, diet, smoking habits, obesity, overall health and soft drink consumption. At the end of the study, those who drank high amounts of soda — an average of five cans per week — were found to be 87 percent more likely to develop pancreatic cancer.
Although the percentage seems high, only 140 people were diagnosed. By contrast, about 6,000 people in the group drank more than two sodas a week and were considered “high soda drinkers.”
That number is much smaller than other studies — some of which have found the same link, Lou Harvin, spokesman for the American Cancer Society, said.
“It’s similar to reports we have seen in the past,” he said, “so it’s not shocking.”
Pancreatic cancer is the fourth most common cause of cancer-related deaths in the United States. The ACS estimates that one in 72 Americans will develop the cancer in their lifetime, with the odds being almost equal between men and women.
In their study, the researchers did not account for diet sodas. It wouldn’t have made sense to study diet sodas in this group, Pereira said, as more than 90 percent of the participants drank regular soda.
The chemical makeup of the sugar in regular soda, mostly high-fructose corn syrup, is different than that of diet soda, Pereira said.
“Those different sugars don’t exist in diet beverages,” he said, “so I don’t really have any reason to believe diet beverages would increase the risk of pancreatic cancer.”
That’s an important question that was left out, said Michelle Duff, director of research and scientific affairs for the Pancreatic Cancer Action Network, as so many Americans drink diet soda.
“You immediately think, ‘Oh gosh, well I drink diet soda, does that count?’ ” she said. “Unfortunately, we don’t have the answer to that by this article.”
Drinking soda spurs a rise in blood sugar, which in turn causes the pancreas to secrete insulin to control it. Insulin stores nutrients and promotes growth, including the growth of tumor cells in the pancreas.
The idea behind the study was to find a causal relationship between cancer and sugar intake, something people have control over and can change, Pereira said.
“It sounds old, silly and trite, but the good thing about this study is it brings that up once again,” Harvin said. “It’s just saying, ‘People, think about what you’re putting into your body, because it’s going to have an impact on how well you live, how long you live and how healthy you’ll be.’ ”
If the connection is simply sugar acting on the pancreas, then these results have implications for other sugar-laden foods, Pereira said, although that would take more research, and it’s more difficult to measure eating habits than beverage consumption.
The study did not find a significant connection between pancreatic cancer and juice for two reasons, Pereira said. First, juice contains naturally occurring sugar, which hasn’t been shown to increase one’s blood sugar as much as soda. Second, it’s sold in much smaller portion sizes.
If juice came in larger portions, the results may have been different, he said.
The more important public health concerns are diabetes, obesity and heart disease, because they affect so many more people, Pereira said. By the end of the study, 6,000 people had type 2 diabetes.
Based on the results, it would be interesting to now explore a possible connection between diabetes and pancreatic cancer, Buss said.
“It’s interesting to see whether we can determine if diabetes could be an early marker,” she said, “because we don’t have early detection methods with this cancer.”
This is the first study of its kind performed on Asians. In previous studies trying to link soda to pancreatic cancer, two found a connection and two did not. Pereira said he wanted to find out whether the connection could apply to populations all over the world.
The American Beverage Association released a statement rejecting the results, highlighting the fact that the National Cancer Institute does not include consumption of sugar-sweetened beverages as a risk factor for pancreatic cancer.
“The fact remains that soft drinks do not cause cancer, nor do any authoritative bodies, such as NCI, name soft drinks as a risk factor for pancreatic cancer,” the statement said. “You can be a healthy person and enjoy soft drinks.”