Sugar And Soda Have A Bad Rep — But How Much Does Just One Can A Day Affect You?
Drinking even a single soda a day may be enough to significantly increase your odds of getting type 2 diabetes, according to a study by the School of Public Health, Imperial College London. These findings dovetail with similar studies conducted in the United States on the role sugared soda plays in triggering insulin resistance among otherwise healthy people.
The European study, which took in data from nearly 30,000 participants, found that people who drink one 12-ounce can of sugar-sweetened soda every day face a 22 percent increase in the risk of developing insulin-resistant diabetes. These results come with a 95 percent confidence interval, making it highly unlikely that they are the result of random effects or unrelated causes.
This link between sugared soda and diabetes came as a surprise to the medical researchers. The link between sugar intake and the incidence of type 2 diabetes has always been controversial, with the consensus view being that sugar intake influences diabetes risk mainly by contributing to weight gain, long known to be a factor in developing the disease. This study, however, draws a line between calories from sugar and calories from other sources, showing that sugar-derived calories are more directly responsible for insulin resistance than had previously been suspected.
In the study, test subjects were contrasted with a control group whose members drank similar quantities of artificially sweetened diet soda. Both groups showed an elevated risk of diabetes, but the control group’s risk seems to be the result of excess weight alone. Once the body mass index of each subject was factored into the numbers, controlling for the higher obesity risk among diet soda drinkers, the effect disappeared for artificial sweeteners, but it remained high for people drinking sugared soda.
Though the European study only considered soda intake as the controlling factor in diabetes risk, another study from UC San Francisco identifies sugar itself as the causative agent. In this study, researchers avoided questions of individual food intake, which is very hard to measure, and focused instead on the amount of sugar found in a population’s food supply. The advantage to measuring population-level food intake lies in working with a large sample group and the ability to track changes over time.
The UCSF researchers discovered that type 2 diabetes rates increase when a population’s food supply becomes more sugary than in the past, then declines as the sugar is withdrawn from the diet. This approach makes the test group its own experimental control, as a single factor is introduced and then withdrawn and the effects measured.
The team’s findings are stark and disturbing. According to the study authors, the incidence of type 2 diabetes increases by 1 percent across the entire population for every increase of 150 sugar-derived calories per person, per day. A 12-ounce can of Coca-Cola delivers 140 calories, and the same serving size of Pepsi has 150, virtually all from sugar. The prevalence of diabetes is expected to increase by 1 percent for each can of regular soda members of the population drink each day.
The studies done so far on the link between sugary soda and type 2 diabetes have delivered such surprising results that it’s difficult for researchers to generalize about their findings. More research, specifically aimed at isolating the direct effect sugar seems to have on diabetes risk, is required before these findings become the basis for public policy. However, the link between regular, sugar-sweetened soda and insulin resistance has clearly been established, which points the way to areas where additional research could be most productive. If you are concerned that you might be at risk of developing diabetes, consult with a doctor or a dietitian to assess your individual risk factors.