How much your friends weigh could influence your own weight, according to a new study published in the journal PLoS ONE.
Researchers from Loyola University found that students were likely to gain weight if their friends were heavier than they were. However, if their friends were leaner, they were more likely to slim down, or gain weight at a slower pace.
In addition, David Shoham, Ph.D., an assistant professor in the Department of Preventive Medicine & Epidemiology of Loyola University Chicago Stritch School of Medicine, and colleagues also found that a student's social network (face-to-face friends, not Facebook friends) influences how much they participate in sports.
Shoham explained: "These results can help us develop better interventions to prevent obesity. We should not be treating adolescents in isolation."
The researchers set out to determine why obesity and related behaviors appear to cluster in social networks. Is it because teenagers make friends with people who look similar to themselves or is it because friends influence one another's behavior?
The team analyzed data from two high schools:
The team analyzed data from 624 students at Jefferson High and 1,151 students at Sunshine Hight.
The researchers found a strong association between obesity and a student's circle of friends. For instance, if a borderline overweight student at Jefferson High had lean friends there was a 40% chance the student's BMI would decrease in the future. However, if they had obese friends their was only a 15% chance the would lose weight.
According to the researchers, their study shows that social influence "tends to operate more in detrimental directions, especially for BMI; a focus on weight loss is therefore less likely to be effective than a primary prevention strategy against weight gain. Effective interventions will be necessary to overcome these barriers, requiring that social networks be considered rather than ignored."
Limitations of the study included:
Written by Grace Rattue
Copyright: Medical News Today
Researchers from Loyola University found that students were likely to gain weight if their friends were heavier than they were. However, if their friends were leaner, they were more likely to slim down, or gain weight at a slower pace.
In addition, David Shoham, Ph.D., an assistant professor in the Department of Preventive Medicine & Epidemiology of Loyola University Chicago Stritch School of Medicine, and colleagues also found that a student's social network (face-to-face friends, not Facebook friends) influences how much they participate in sports.
Shoham explained: "These results can help us develop better interventions to prevent obesity. We should not be treating adolescents in isolation."
The researchers set out to determine why obesity and related behaviors appear to cluster in social networks. Is it because teenagers make friends with people who look similar to themselves or is it because friends influence one another's behavior?
The team analyzed data from two high schools:
- Jefferson High - located in a rural area and has primarily white students
- Sunshine High - located in an urban area with a substantial racial and ethnic diversity
The team analyzed data from 624 students at Jefferson High and 1,151 students at Sunshine Hight.
The researchers found a strong association between obesity and a student's circle of friends. For instance, if a borderline overweight student at Jefferson High had lean friends there was a 40% chance the student's BMI would decrease in the future. However, if they had obese friends their was only a 15% chance the would lose weight.
According to the researchers, their study shows that social influence "tends to operate more in detrimental directions, especially for BMI; a focus on weight loss is therefore less likely to be effective than a primary prevention strategy against weight gain. Effective interventions will be necessary to overcome these barriers, requiring that social networks be considered rather than ignored."
Limitations of the study included:
- The data was collected over 10 years ago - prior to Facebook and when childhood obesity rates were significantly lower
- The model makes assumptions about how friendships form, are maintained, and dissolve, which the researchers where not able to test directly
- Social network studies are observational rather than experimental, which limits researchers' ability to call the associations causal
Written by Grace Rattue
Copyright: Medical News Today
