Jericho
New member
Article from Newsweek for your opinions:
Does Soda Cause Pancreatic Cancer? What the Latest Study Really Says.
Ian Yarett
Early last week headlines hyped intriguing new research linking consumption of sugar-sweetened soda with increased risk of pancreatic cancer (see coverage here and here, for example). At first glance, this sounds huge—the very notion that drinking only two glasses of soda each week could increase your pancreatic-cancer risk by 87 percent is shocking. The seriousness of pancreatic cancer (which has a five-year survival rate of less than 5 percent) and limited medical knowledge of what causes the disease made the research seem even more relevant.
But there’s a problem: the research, published in the February issue of Cancer Epidemiology, Biomarkers & Prevention, is very preliminary and has some serious limitations. Not to mention that much of the news coverage failed to clearly explain the 87 percent figure: since pancreatic cancer is so rare (about 12 cases per 100,000 people each year), an 87 percent increased risk does not amount to a very high absolute risk. In other words, the incidence of pancreatic cancer amounts to a baseline 0.01 percent chance of any given person developing the disease (genetics and other factors notwithstanding). Increasing that chance by 87 percent would only raise the risk to a still measly 0.02 percent—not exactly something to write home about.
In brief, the study (described in greater detail here) looked at 60,524 adult Chinese in Singapore, assessing their soft-drink intake through a questionnaire that was part of the Singapore Chinese Health Study. Health outcomes were determined for each subject after the follow-up period (about 11 years per participant).
The study’s senior author, University of Minnesota epidemiologist Mark Pereira, says that his study contributes to what we know about the potential role of soft drinks in the risk for pancreatic cancer, but notes that similar research in the past has had mixed results. There have been four prior studies in Caucasian populations, although only two of them found a positive link between soda and pancreatic cancer.
The present study can’t be used to suggest that soda consumption causes pancreatic cancer; it only shows that soda drinkers tend to get pancreatic cancer at a higher rate than non–soda drinkers in the studied population.
“We know that people who drink a lot of soda also tend to eat an unhealthy diet and exercise less,” says Frank Hu, a professor of nutrition and epidemiology at Harvard. So it’s possible that other unhealthy choices that soda drinkers make are leading to the observed increase in pancreatic cancer, rather than the soda consumption itself. Although the study statistically adjusted for known risk factors of pancreatic cancer (like smoking and eating overcooked red meat), Pereira says that it’s impossible to adjust perfectly because not all risk factors are known and measured.
In the present study, the group of participants that consumed the most soda was very small—fewer than 6,000 individuals—which limits the statistical power of the results. The gold standard for determining whether avoiding or reducing soda consumption could lower the risk of pancreatic cancer would be to use a randomized clinical trial, but that would be extraordinarily expensive and require hundreds of thousands of participants, so it’s unlikely to ever happen. Another study like Pereira’s, but with a larger number of subjects (at least 100,000), would be more feasible yet still valuable because more soda drinkers would presumably be included, Hu says.
Despite all the soda Americans drink (about 50 gallons per person each year, more than enough to fill an entire bathtub), it’s important to remember how rare pancreatic cancer is and therefore how small a role soda probably plays in development of the disease, even if the proposed link between soda consumption and pancreatic cancer holds up to further study. “At most, it’s probably a very small piece of the puzzle,” Pereira says.
But he also makes another key point: we don’t really need any more research on reasons to moderate soft-drink intake, regardless of the possible link between soda and pancreatic cancer that his study proposes. “We already have big problems with dental health, obesity, and type 2 diabetes—and those are much more important and prevalent and cause a lot more problems than pancreatic cancer when you look at the numbers,” Pereira says.
According to Hu, the evidence implicating sugar-sweetened soda in diseases like obesity and type 2 diabetes is solid. Well-designed, rigorous observational studies suggest that soda is a factor leading to type 2 diabetes, and even some randomized clinical trials have found that removing soda from schools or reducing soda consumption at home can reduce the risk of childhood obesity (one study showed that a very modest reduction in soft-drink consumption led to an 8 percent reduction in obesity). “The picture is emerging that soda consumption is causally related to the development of obesity, type 2 diabetes, and metabolic diseases,” Hu says.
The bottom line is that there’s really no scientifically supported reason to avoid soda for fear of pancreatic cancer—at least not yet. But then again, if this research encourages people to drink less soda, that might not be such a bad side effect.
Does Soda Cause Pancreatic Cancer? What the Latest Study Really Says.
Ian Yarett
Early last week headlines hyped intriguing new research linking consumption of sugar-sweetened soda with increased risk of pancreatic cancer (see coverage here and here, for example). At first glance, this sounds huge—the very notion that drinking only two glasses of soda each week could increase your pancreatic-cancer risk by 87 percent is shocking. The seriousness of pancreatic cancer (which has a five-year survival rate of less than 5 percent) and limited medical knowledge of what causes the disease made the research seem even more relevant.
But there’s a problem: the research, published in the February issue of Cancer Epidemiology, Biomarkers & Prevention, is very preliminary and has some serious limitations. Not to mention that much of the news coverage failed to clearly explain the 87 percent figure: since pancreatic cancer is so rare (about 12 cases per 100,000 people each year), an 87 percent increased risk does not amount to a very high absolute risk. In other words, the incidence of pancreatic cancer amounts to a baseline 0.01 percent chance of any given person developing the disease (genetics and other factors notwithstanding). Increasing that chance by 87 percent would only raise the risk to a still measly 0.02 percent—not exactly something to write home about.
In brief, the study (described in greater detail here) looked at 60,524 adult Chinese in Singapore, assessing their soft-drink intake through a questionnaire that was part of the Singapore Chinese Health Study. Health outcomes were determined for each subject after the follow-up period (about 11 years per participant).
The study’s senior author, University of Minnesota epidemiologist Mark Pereira, says that his study contributes to what we know about the potential role of soft drinks in the risk for pancreatic cancer, but notes that similar research in the past has had mixed results. There have been four prior studies in Caucasian populations, although only two of them found a positive link between soda and pancreatic cancer.
The present study can’t be used to suggest that soda consumption causes pancreatic cancer; it only shows that soda drinkers tend to get pancreatic cancer at a higher rate than non–soda drinkers in the studied population.
“We know that people who drink a lot of soda also tend to eat an unhealthy diet and exercise less,” says Frank Hu, a professor of nutrition and epidemiology at Harvard. So it’s possible that other unhealthy choices that soda drinkers make are leading to the observed increase in pancreatic cancer, rather than the soda consumption itself. Although the study statistically adjusted for known risk factors of pancreatic cancer (like smoking and eating overcooked red meat), Pereira says that it’s impossible to adjust perfectly because not all risk factors are known and measured.
In the present study, the group of participants that consumed the most soda was very small—fewer than 6,000 individuals—which limits the statistical power of the results. The gold standard for determining whether avoiding or reducing soda consumption could lower the risk of pancreatic cancer would be to use a randomized clinical trial, but that would be extraordinarily expensive and require hundreds of thousands of participants, so it’s unlikely to ever happen. Another study like Pereira’s, but with a larger number of subjects (at least 100,000), would be more feasible yet still valuable because more soda drinkers would presumably be included, Hu says.
Despite all the soda Americans drink (about 50 gallons per person each year, more than enough to fill an entire bathtub), it’s important to remember how rare pancreatic cancer is and therefore how small a role soda probably plays in development of the disease, even if the proposed link between soda consumption and pancreatic cancer holds up to further study. “At most, it’s probably a very small piece of the puzzle,” Pereira says.
But he also makes another key point: we don’t really need any more research on reasons to moderate soft-drink intake, regardless of the possible link between soda and pancreatic cancer that his study proposes. “We already have big problems with dental health, obesity, and type 2 diabetes—and those are much more important and prevalent and cause a lot more problems than pancreatic cancer when you look at the numbers,” Pereira says.
According to Hu, the evidence implicating sugar-sweetened soda in diseases like obesity and type 2 diabetes is solid. Well-designed, rigorous observational studies suggest that soda is a factor leading to type 2 diabetes, and even some randomized clinical trials have found that removing soda from schools or reducing soda consumption at home can reduce the risk of childhood obesity (one study showed that a very modest reduction in soft-drink consumption led to an 8 percent reduction in obesity). “The picture is emerging that soda consumption is causally related to the development of obesity, type 2 diabetes, and metabolic diseases,” Hu says.
The bottom line is that there’s really no scientifically supported reason to avoid soda for fear of pancreatic cancer—at least not yet. But then again, if this research encourages people to drink less soda, that might not be such a bad side effect.
