Your friends on Facebook and your friends down the street — or even friends that live hundreds of miles away — may hold a lot of power when it comes to your health. Whether online or offline, your friends are part of your social network, and these connections may be the key to making lasting, positive changes in your life.
That’s the topic of a new book called The Social Network Diet, by Miriam Nelson and Jennifer Ackerman, and it’s the focus of several new studies. Co-author Miriam Nelson wrote about the social network influence for the Huffington Post, and it was the topic of my recent post for WebMD.
This social network effect was first observed several years ago when Harvard researchers released a study that tracked more than 12,000 people for three decades and found that the risk of becoming obese spread almost like a virus from person to person. Friends are more powerful than our genes when it comes to weight gain, the researchers concluded. A person’s chance of becoming obese climbed by 57 percent if a friend of the same sex became obese. This effect was even stronger among close friends. Among close mutual friends, if one friend became obese, the other friend’s chances increased by 171 percent.
So what’s going on? Miriam Nelson, a nutrition researcher at Tufts University, believes that when someone becomes obese, it becomes more socially acceptable for people close to that person to gain weight. The change in social norm of acceptable body size can spread quickly, rippling through social networks, even among people who live hundreds of miles away from one another. She believes that these changing norms are one reason for the rapid spread of obesity.
On the positive side, there’s growing evidence that losing weight may be similarly “contagious.” Read more about the power of social networks at Real Life Nutrition on WebMD.