Adherence
Obesity spreads through social networks via interpersonal induction, where a person's risk of becoming obese increases significantly if their friends, siblings, or spouses become obese, independent of geographic proximity.
Your social circle matters for your weight. If your close friends or family members gain weight, your own risk of gaining weight increases, likely due to shifting norms and shared behaviors. To maintain a healthy weight, consider how your social network influences your habits and seek supportive relationships that align with your health goals.
A person’s chances of becoming obese increased by 57% (95% confidence interval [CI], 6 to 123) if he or she had a friend who became obese in a given interval... These effects were not seen among neighbors in the immediate geographic location.
Why this rating
Large longitudinal dataset (Framingham, 32 years, 12,000+ subjects) with rigorous statistical controls for homophily and genetics, though observational design limits causal certainty.
Source
The Spread of Obesity in a Large Social Network over 32 Years
Nicholas A. Christakis et al. · New England Journal of Medicine · 2007
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