PureInsight | March 25, 2007
Independent research finds that high consumption of soft drinks increases the risk of diabetes. Industry-funded research should be viewed with caution.
Sugar is often targeted as unhealthy and to be avoided. And rightly so, since sugar consumption has been linked with an increased risk of a range of ills, most notably obesity.
Some of the research that has examined the health effects of sugar has focused on sugary soft drinks. This type of beverage is particularly hazardous because it contains so much sugar (9 teaspoons of sugar in an 11-ounce can is typical), and that this glut of sugar can be consumed so quickly.
The rush of readily available sugar into the system can induce biochemical changes (specifically, the secretion of insulin) that can lead to weight gain. Also, the higher levels of insulin that come after downing a sugary drink may, in the long term, increase the risk of other conditions including type-2 diabetes, too.
In the February edition of the American Journal of Public Health, U.S.-based researchers examined the relationship between the consumption of sugary soft drinks and health.
This study cites evidence that assessed the link between the consumption of soft drinks and type-2 diabetes in a group of more than 91,000 women followed over an 8-year period. This study found that women consuming one or more cans of soda per day, compared to those drinking less than one can of soda per month, were twice as likely to develop type-2 diabetes.
The American Journal of Public Health authors went further and looked at the relationship between soft drink consumption and a variety of other nutritional and health factors including calorie intake and body weight. In these analyses, the results from studies funded by the food industry were separated from those that were independently funded.
The results revealed that studies funded by industry reported much smaller adverse effects on nutrition or health compared to independently-funded research. For example, independently-funded research found what appeared to be a significant link between the consumption of sugary soft drinks and body weight, while industry-funded research did not.
This finding is in keeping with recent research that found that industry-funded research into soft drinks, milk, and fruit juices reports significantly more favorable results than independently funded work.
One of the authors of the American Journal of Public Health study, Dr. Kelly Brownell, Director of the Rudd Center for Food Policy and Obesity at Yale University, is reported by Reuters as saying: "The bigger issue here, in this arena in particular but in science in general, is how you can get a distorted view of reality if industry-funded studies are considered in the mix—and they usually are—especially when industry uses these studies in advertising, lobbying, and in talking to the press."
Dr. Brownell's study clearly highlights the need for us to treat not only sugary soft drinks, but also the research funded by those that manufacture them, with extreme caution.
References:
1. Vartanian LR, et al. Effects of Soft drink Consumption on Nutrition and Health: A Systematic Review and Meta-Analysis. American Journal of Public Health 2007 Feb 28; [Epub ahead of print]
2. Schulze MB, et al. Sugar-sweetened beverages, weight gain, and incidence of type 2 diabetes in young and middle-aged women. JAMA (Journal of the American Medical Association). 2004; 292(8): 927-34.
3. Lesser LI, et al. Relationship between Funding Source and Conclusion among Nutrition-Related Scientific Articles. PLoS Medicine 4(1): e5 doi: 10.1371/journal.pmed.0040005
Dr John Briffa is a London-based doctor, author, and health writer with an interest in nutrition and natural medicine.
