To a meaningful degree, yes. Habits and behaviors spread through social circles. The people around you shape what feels normal, and what feels normal shapes what you do.

What the research says

In 2007, Nicholas Christakis and James Fowler published a study in the New England Journal of Medicine that followed more than 12,000 people over 32 years. A person's chance of becoming obese rose sharply when a close friend became obese. Later work by the same researchers found similar patterns for smoking, quitting smoking and happiness.

The effect wasn't just about people choosing similar friends. It followed the direction of the friendship over time, which suggests friends were influencing each other.

What the research can't say

These findings have been debated. Other researchers have pointed out that it's hard to fully separate influence from shared environment and similar people finding each other. The effect is real enough to matter, but you aren't simply a copy of your friends.

The habit: choose your influences on purpose

You can't control every influence in your life, but you can choose who you spend the most time with.

  • Notice which friends make you want to be better and which ones pull you toward habits you're trying to leave.
  • Spend more time with people already living the way you want to live.
  • Join groups built around the habits you want: a running club, a Bible study, an investing group, a gym.

The rule that makes it stick: put yourself in the right rooms

It's easier to change your surroundings than your willpower. If you want to exercise, spend time with people who exercise. If you want to save, spend time with people who don't spend for show. The habit comes easier when it's normal in the room.

This week

Find one group that meets regularly around a habit you want to build, and go once.

The keep

Choosing your influences costs some comfort and sometimes some distance. It puts you in rooms where the right choices feel normal.

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