June 28, 2016
A new study by researchers from the UNC Gillings School of Global Public Health has found that replacing even one daily serving of sugar-sweetened beverages (SSB) such as soda with water could result in a meaningful reduction in caloric intake and associated weight gain.
The study co-authors are Jennifer Poti, PhD, research assistant professor of nutrition at UNC Gillings, and Kiyah J. Duffey, PhD, Gillings School alumna and adjunct assistant professor of human nutrition, foods and exercise at Virginia Tech. Duffey acted as lead author on a paper titled, “Modeling the effect of replacing sugar-sweetened beverage consumption with water on energy intake, HBI score, and obesity prevalence,” published online June 28 by the journal Nutrients.
Beverages are a significant factor in the daily diets of adults in the United States, which explains why SSB like soda and sweetened fruit drinks are at the center of many obesity-related policy debates. The new study shows how even incremental changes in this behavior can make a significant difference in calorie consumption.
To examine the impact that replacing one eight-ounce serving of SSB with water might have on both Healthy Beverage Index (HBI) scores and obesity prevalence, the investigators used nationally representative data from 16,429 adults. Based on information from the 2007-2012 National Health and Nutrition Examination Survey (NHANES) and the ‘What we Eat in America’ dietary intake portion of the NHANES datasets, Poti and Duffey conducted statistical analyses to calculate the predicted impact of a water-for-SSB substitution.
“We found that about 30 percent of U.S. adults drink more than two servings of SSB on any given day, and another 15 percent drink one to two servings,” Poti said. “So, we wanted to investigate whether even small decreases in the amount of SSB people drink could lead to meaningful changes in diet or weight status.”
Analysis revealed that replacing one eight-ounce serving of SSB with water lowered the percent of calories obtained from beverages from 17 to 11 percent (among adults consuming one serving of SSB per day). The researchers also noted a 9 to 21 percent improvement in HBI score among adults who replaced one serving of SSB with water.
Using previously published meta-analyses that measured weight loss, the investigators also predicted a reduction in the prevalence of obesity (observed: 35.2 percent; predicted 33.5 to 34.9 percent) and increase in the prevalence of normal weight (observed: 29.7 percent; predicted: 31.3 percent).
These results provide further epidemiologic evidence that drinking water in place of SSB can be used as a strategy to reduce caloric consumption and help individuals meet recommendations for healthy beverage intake. Previous research documenting the impact of SSB reduction on body weight is unequivocal, and this study adds the nuance that replacing even one serving of SSB per day could help limit excessive calorie intake and associated weight gain.