For 30 days, students at two Ohio high schools were encouraged to cut down on soda and other unhealthy drinks. And it worked.

Want your teen to lay off sugary drinks? The solution may be peer pressure.

A 30-day “Sodabriety” challenge and study conducted by Ohio State University found that encouraging teens to lay off sodas reduced their consumption of the sugary drinks. During the challenge, the number of students who do not consume sugary drinks increased by two thirds. It was conducted at two schools, where 186 students took part.

Not only did the challenge encourage kids to cut down on soda, it included reducing consumption of sports and energy drinks, flavored milk, and coffee. They were encouraged to cut down—not eliminate—their drink consumption.

What worked? The students created teen advisory councils at the two rural high schools. They came up with marketing campaigns, presentations, and blasted a short fact over the loudspeaker during morning announcements throughout the 30-day span of the challenge.

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Laureen Smith, lead study author and an associate professor at Ohio State University, originally set out to study the prevalence of type 2 diabetes in Appalachian Ohio. She says parents kept mentioning the amount of sugary sodas their teens were drinking, so she decided to try a dietary intervention instead.

“I think that peer support was the strongest factor that led to the change. Students wanted to do it because their friends were,” said Smith, adding that there were no changes in the availability of sugary drinks or how they were sold at the two schools.

Smith found that 92 percent of students preferred soft drinks to healthier fare, both before and after the study. In total, 63 percent of the students drank sugary beverages at least three days a week—more than one-third said it was a daily occurrence.

One month after the challenge ended, nearly 60 percent of the students said they had cut consumption of sugary drinks to fewer than three days a week. During the intervention and over the month after it ended, they lowered their overall consumption of sugary drinks by nearly 30 percent. Smith also noticed that students lowered their servings of sugary drinks from an average of 2.3 to 1.3 per day.

Many students turned to water instead. In fact, the students were found to be drinking about 5.5 servings of water per day by the challenge’s end—30 percent higher than when it started.

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Smith isn’t stopping there. She wants to perform another school-based challenge that involves students’ family members. She said that siblings may have a positive influence on each other. Social media could be another avenue to promote the message.

“I think this study can be replicated at a larger scale and with other populations,” Smith said. “After all, we are all connected to friends and social networks. These connections influence us and our behaviors. We propose using these natural relationships to impact behaviors in a healthful way.”

In the long run, Smith hopes that a drop in the use of sugary drinks could help curb type 2 diabetes in rural communities. Through this study and previous work, she has found that teens can be effective at changing their friends’ behavior.

Not only did the students in her intervention lower their sugar consumption, Smith said, “many of the participants told us of losing weight, having more energy, and better skin. We need to track and measure these possible effects.”

A report from the Centers for Disease Control and Prevention (CDC) has found that 80 percent of young adults—especially those between 12 and 19 years old—drink sugar-sweetened beverages every day. Those drinks make up anywhere from 13 to 28 percent of their daily intake of calories. Children in the Appalachian region were shown to have higher rates of consumption compared to others their age, Smith reported.

“We tend to think first of risky behaviors when we study adolescents, but they do positive things, too,” Smith said. “With the right guidance and support, they are powerful influencers. We might as well use peer pressure to our advantage.”

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