The people you spend the most time with can shape more than your interests, habits, and weekend plans. According to a growing body of research, your social circle may also have a meaningful influence on your physical and mental health.
From the foods you eat to how often you exercise, sleep, and even manage stress, researchers have found that healthy behaviours often spread through close relationships. While everyone’s choices are ultimately their own, studies suggest that friends can have a surprisingly powerful impact on the decisions we make every day.
One of the most influential studies on the topic, published in the New England Journal of Medicine, found that health-related behaviours can spread through social networks. Researchers observed that habits such as smoking, physical activity, and body weight were influenced not only by close friends but also by family members and other social connections. The findings suggest that our behaviours are shaped, at least in part, by the people we regularly interact with.
Health experts say this influence often happens subtly. If your friends enjoy cooking nutritious meals, going for walks, or signing up for fitness classes, you’re more likely to see those behaviours as normal and join in. On the other hand, social groups can also reinforce less healthy habits, whether that’s eating out frequently, drinking more alcohol, or leading a more sedentary lifestyle.
The effects extend beyond physical health. Research has consistently shown that strong social connections are associated with lower levels of stress, reduced feelings of loneliness, and better overall mental well-being. Having supportive friendships can provide emotional encouragement during difficult times while also helping people stay motivated to maintain healthy routines.
Of course, friendship isn’t about finding people with perfect habits. It’s about surrounding yourself with people who encourage positive choices and make it easier to stick with them. A friend who invites you on a hike instead of staying inside, checks in on your goals, or simply offers support during challenging moments can make a meaningful difference over time.
The good news is that positive influence works both ways. Just as your friends can affect your health, your own habits can inspire those around you. Choosing to prioritize movement, healthy eating, or stress management may encourage others in your circle to do the same.
While no friendship determines your future health, research suggests that the people you spend time with matter more than many of us realize. Building relationships that support both your happiness and your well-being may be one of the healthiest choices you can make.