There are plenty of reasons to adopt healthy habits in your own life, but here’s one you may not have thought of: It can help people you care about to be healthier, too. A large body of research suggests that healthy lifestyle behaviors are literally contagious. For example, in a survey of more than 15,000 people in 12 countries by the public relations agency Edelman, nearly half of respondents said their friends and family members had the biggest impact on their lifestyle as it relates to health.
Here are six ways to use your own health behavior to inspire change in others.
1. Eat healthfully.
If you eat well, chances are your loved ones will too. In the Edelman survey, more than one-third of respondents said their friends and family have the greatest impact on their nutrition. Indeed, a review of 69 studies published in March 2015 in the journal Appetite found that children mimic the healthy eating habits of their parents and peers, which can lead to a higher intake of vegetables and low-fat foods. Loved ones also influence the quantity of food we consume: A person who overeats can influence dining companions to do the same, while lighter eaters tend to inspire others to consume less.
2. Slim down.
If you’re trying to lose weight, research shows that you have the power to help a loved one do the same. In a study published in Obesity in 2011, researchers found that overweight and obese young adults who believe their overweight and obese friends, family, and partners are trying to lose weight are more likely to follow suit.
You may be able to help a friend shed pounds even if you don’t need to lose weight yourself. A 2012 study of high school students in the journal PLOS ONE found that those who were borderline overweight (body mass index, or BMI, of 25) were more likely to lose weight over the course of a year if their friends were mostly slim (average BMI of 20) vs. if their friends were obese. The findings suggest that body weight may be "contagious" within social groups.
3. Work out.
In a study published in Psychology of Sport and Exercise in 2011, researchers found that people were more likely to work out if their romantic partners did so as well. They also exercised if their best friends did, but only if they felt like those friends were encouraging and supportive of them. (Perceived social support was especially important for women, the authors found.) Aside from the health benefits, exercising with someone you’re close to can help strengthen your relationship, since it enables you to spend time together plus gives you shared experiences to talk about.
4. Quit smoking.
Smoking is largely a social behavior, so a person who quits can have a powerful influence on friends or relatives who smoke—in part by providing one fewer person for them to light up with. In one of the largest studies to date of the collective dynamics of smoking behavior, published in the New England Journal of Medicine in 2008, researchers found that if a spouse stopped smoking, his or her partner was 67 percent less likely to smoke. If a friend quit, a person’s chances of smoking dropped by 36 percent. If a sibling quit, the chances fell by 25 percent. The researchers also found that even coworkers at small companies (up to six employees) influence each other’s smoking habits: If one person quit, the likelihood that a coworker would light up decreased by 34 percent.
5. Limit alcohol.
A friend or relative who drinks more than a moderate amount of alcohol might be inspired to abstain if you become a teetotaler. In a study published in the Annals of Internal Medicine in 2010, a husband was 74 percent more likely to abstain from drinking if a wife did so; a wife was 56 percent more likely to stop drinking if her husband quit; and friends were around 40 percent more likely to abstain if their pals did the same. If a brother abstained, a sibling was 39 percent more likely to stop drinking; if a sister did so, there was a 28 percent chance a sibling would abstain. There was no effect, however, for other personal contacts, such as next-door neighbors and coworkers.
6. Get vaccinated.
You’ll reduce the chance that you’ll infect loved ones with a dangerous illness such as the flu, pneumonia, hepatitis, meningitis, or pertussis (whooping cough). Some people are especially vulnerable to certain illnesses and may be unable to get certain vaccines against them, including pregnant women, infants, and immunocompromised people. For example, newborns under two months old are too young to be vaccinated for whooping cough, which is particularly dangerous for babies. Eighty percent of babies who catch whooping cough get it from a parent, sibling, grandparent, or babysitter, according to the CDC. Read about vaccines all adults should have.