The Phenomenal Impact Your Friends Have on Your Willpower (For Better or Worse)

The town was Framingham, Massachusetts – a simple place in the Northeastern United States with a population of approximately 68,000. It is a lovely town with a mix of old colonial ties and new developments. It is a town so nice that in 2012, Framingham was listed by CNN Money Magazine as the 36th best place to live in the United States. 

But the town has a dark side that many people do not know about.

Since 1948, the town has endured an epidemic of a very specific disease. This particular disease is as deadly as there is in America. It has taken countless lives and it seems like the more we try to control the problem, the larger it gets. This epidemic is not HIV, cancer, or even drug use. This epidemic is obesity. [1]


In 1948, researchers began tracking residents of Framingham to discover what causes an obesity epidemic. They started with 5,200 residents and added new generations in 1971 and 2002.

What they found over 50+ years of research is shocking. Obesity is indeed infectious. Just like a disease, it spreads within families. It spreads within work environments and it spreads within friend groups.

If someone’s friend in Framingham became obese, their own likelihood of becoming obese increased by 171%!

Regardless of the person's lifestyle, health, or self-discipline, if their friend started eating fast-food too often, chances are they were soon to follow. Similar results remained constant throughout the duration of the study. As obesity became a greater national problem, it became a greater Framingham problem.

However, despite the fact that the researchers were just interested in obesity, they began to notice other patterns emerging as well. It seemed that obesity was not the only thing that spread like an epidemic in Framingham.

Researchers also found that if one person started smoking, all of her friends were now also at risk of getting on a pack of cigarettes-a-day. Similarly, if someone began to hit the bar after work, it would not be too long before his coworkers were also waking up with hangovers the next morning.

It seemed like no matter what the vice was, if one person started, his social network was soon to follow.

Things seemed bleak. But then the researchers came across some good news – vices were not the only things that were contagious!

They also found that if your friends started going to the gym, you were likely to join them. If your family began shopping at the farmer’s market, you would begin eating locally as well. Whether it is a virtue or a vice, we follow the habits of our social networks.


This behavior can be traced back to our ancestors and our desire to remain in the tribe. We want to act like the people around us. If we act like them, they are more likely to like us. If they like us, we are more likely to stay in the tribe and therefore stay safe. [2]

Because of this importance, we developed something in the brain known as “mirror neurons”. These mirror neurons cause us to look at the behavior of others and begin to act in the same manner. [3]

If we see people smoking, then we have a natural desire to do the same – no matter how many warning labels we see. If we see others indulging in cheesecake, we have a natural desire to indulge as well – regardless of those weight loss goals we set a month ago. And if we see others starting to exercise, we get a sudden motivation to not be seen as "lazy".

So if we want to achieve something great, we don't just need to look in the mirror, we also need to look at our social networks.

Allies or accomplices?

Building upon the research done in Framingham, behavioral psychologist, Al Switzler, and his colleagues sought to measure the impact of people's social networks while working toward specific behavior change.

To do this, they took a sample of 5,000 participants who were all seeking to lose a significant amount of weight. They then tracked these participants over 3 years to determine who was successful in their weight loss and why. [4]

The researchers found that those who were successful in their weight loss all used their social networks for support. They all spoke openly and honestly with them about why they wanted to change their behavior and how their friends and family could aid them in their efforts.

By opening up and sharing their goals, these people turned their friends into allies. They became a means of support for helping them get through the many hours of struggle and temptation that they had to deal with. Then, just like in Framingham, many of these allies began their own diet and exercise plans! Leading to a chain reaction of positive lifestyle changes for the whole social network.

The ones who were unsuccessful in their behavior change, however, did not open up to their friends and family about their goals. This led to many friends - even with the best of intentions - to not become allies, but accomplices. 

Rather than helping to motivate and support their friends through the hours of struggle and temptation, these social networks sought to ease their pain. They saw their friends struggling to make it to the gym and offered the advice that they "start taking it easy" or "give themselves a break". 

These friends may have meant well, but rather than supporting their goals, they provided justification for taking the easy way out. And in the end, while those with allies created a chain reaction of positive behavior, those with accomplices dug themselves into an even deeper hole.


There was one key difference between those who turned their friends into allies and those who turned them into accomplices - vulnerability.

Those who were open, honest, and willing to ask for help, showed how committed they were to their goal. They communicated exactly what they needed from their friendships in order to change their behavior and achieve the happiness they sought. Because the message was clear, these friends knew their duty and provided genuine help.

Those who weren't vulnerable, and willing to admit that they needed support, didn't send this clear message to their social networks. Therefore their friends couldn't provide great support because they didn't know how. They didn't know that the participants needed them to provide that extra push. So rather than helping them in their time of need, they sought to ease their pain by suggesting the easy way out.

Your friends have a powerful influence on your behavior. Genuine friends will always want the best for you, but they need to know what they can do to help. If you do not communicate your goals to them and let them know how they can support you, they cannot help you - and may just end up hurting you. 

So open yourself up to them, share your struggles, and ask for support. This may just create a chain reaction that leads to a happier, healthier, life for your entire social network!


Since we first started living in tribes, we have sought the approval of others. We crave it. Even to a point where one person's lifestyle change can spread like an epidemic across an entire community.

This phenomenon can be either good or bad. We can use the influence of others for motivation to achieve more, or justification for giving up. In the end, it all comes down to whether we are brave enough to be vulnerable, admit that we need support, and allow our friends and family to be allies, not accomplices.


  1. Wong, N., Levy, D., & Narula, J. (1948). Framingham Heart Study: An Enduring Legacy. Global Heart, 1-2.
  2. Dunbar, R.i.m. "TSB: Mind, Language, and Society in Evolutionary Perspective." Annual Review of Anthropology 32.1 (2003): 163-81.
  3. Humphrey, Nicholas. The Inner Eye: Social Intelligence in Evolution. Oxford: Oxford UP, 2002. Print.
  4. Patterson, Kerry, Joseph Grenny, David Maxfield, Ron McMillan, and Al Switzler. Change Anything: The New Science of Personal Success.