A new study shows that teenagers can be persuaded to cut back on sugary soft drinks - especially with a little help from their friends.
A 30-day challenge encouraging teens to reduce sugar-sweetened drink use lowered their overall consumption substantially and increased by two-thirds the percentage of high-school students who shunned sugary drinks altogether.
The "Sodabriety" challenge, piloted by Ohio State University researchers, was an effort to confront the largest source of added sugar in the U.S. diet: sugar-sweetened soft drinks, sports and energy drinks, and flavored milk and coffee.
Students were tapped to establish teen advisory councils, whose members led the interventions at two rural Appalachian high schools. They designed marketing campaigns, planned school assemblies and shared a fact per day about sugar-sweetened drinks over the morning announcements.
The primary message to their peers: Try to cut back on sugar-sweetened beverages for 30 days. Students opted not to promote eliminating these drinks entirely during the challenge.
Overall, participating teens did lower their intake of sugary drinks, and the percentage of youths who abstained from drinking sugar-sweetened beverages increased from 7.2 percent to 11.8 percent of the participants. That percentage was sustained for 30 days after the intervention ended.
In an unexpected result, water consumption among participants increased significantly by 60 days after the start of the program, even without any promotion of water as a substitute for sugar-sweetened drinks.
"The students' water consumption before the intervention was lousy. I don't know how else to say it. But we saw a big improvement in that," said Laureen Smith, associate professor of nursing at Ohio State and lead author of the study. "And there was a huge reduction in sugar-sweetened beverage consumption. The kids were consuming them fewer days per week and when they were consuming these drinks, they had fewer servings."
Smith co-authored the study with Christopher Holloman, associate professor of statistics at Ohio State. The research is published in a recent issue of the Journal of School Health.
Smith originally set out to conduct a community-based study concerning the prevalence of Type 2 diabetes in Appalachian Ohio. Through a series of meetings, surveys and focus groups, parents in these communities tended to express concern about kids' diets.
"Sugar-sweetened beverages kept coming up," Smith said.
According to the Centers for Disease Control and Prevention, about 80 percent of youths - especially those age 12 to 19 years - consume sugar-sweetened beverages daily, and these drinks contribute between 13 and 28 percent of their daily calorie intake. Children and adolescents in Appalachia have higher rates of sugary beverage consumption compared with others of the same age.
In all, 186 students at two high schools participated in the challenge - almost half of each school's headcount, and almost 70 percent of eligible students when teens attending vocational training were excluded.
Smith surveyed the students about vending machine access and beverage options, sugar-sweetened beverage drinking habits and water consumption. Once the intervention began, students were instructed to keep a log, recording how many servings of sugary drinks and other beverages they consumed each day.
For this study, sugar-sweetened beverages included regular soft drinks, sweet tea, fruit drinks, sports drinks, energy drinks, flavored or sweetened milk, coffee with sugar, other coffee drinks and an "other" category. Regular soft drinks were the preferred beverage for 92 percent of sugary drink users before and after the study.
At baseline, nearly half - 41 percent - of the students reported buying sugary drinks from school-based sources: vending machines, the cafeteria or school stores. In addition, 63 percent of students reported consuming sugary drinks at least three days a week, with more than a third reporting daily intake of these beverages - a figure that dropped to 7.2 percent of students immediately after the challenge ended.
One month after the intervention ended, almost 60 percent of students reported consuming sugary drinks fewer than three days each week. Over the course of the study, from the start of the challenge until a month after it ended, respondents achieved a nearly 30 percent reduction in days per week that they consumed sugary drinks.
A similar pattern was seen in servings: The intervention reduced average daily servings of sugar-sweetened beverages from 2.3 to 1.3 - about one serving, or 8 ounces, per day.
Water consumption increased from baseline to immediately after the challenge ended, and continued to increase over the next 30 days to an average of 5 ½ servings of water per day, reaching a 30 percent increase from baseline measures.
Smith heard from students that they had lost weight, felt better and had recruited parents to join them in the challenge. Based on this anecdotal data, she plans to follow up with a similar school-based challenge that includes measures of health outcomes and involvement of students' families.
In the long run, Smith hopes a drop in the use of sugary drinks could help curb Type 2 diabetes in rural communities. Through this study and previous work, she also has found that teens can be effective at changing peer behavior.
"We're teaching kids to help themselves, and it's a really cost-effective way of promoting health and delivering a message," she said. "We tend to think first of risky behaviors when we study adolescents, but they do positive things, too. With the right guidance and support, they are powerful influencers. We might as well use peer pressure to our advantage."