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The many health benefits of having friends

The lasting importance of friendship. (Photo: Getty Images)

Mary and Joyce met while in nursing school, just a few months after their high school graduation. The year was 1957, when gas cost 23 cents a gallon and the Frisbee was invented. Mary and Joyce quickly became best friends, like peas and carrots, as Forrest Gump might say. They double-dated, were in each other’s weddings, and had children only months apart. Even after Mary and her husband moved away, the friends maintained their close relationship. When they reconnected in the same zip code during the 1980s, it blossomed all over again.

Mary believes their 60-year friendship has had a positive impact on her well-being. “We subtly encourage each other or give each other hell,” Mary tells Yahoo Lifestyle. “We enjoy a lot of same things, as well as admire each other’s accomplishments.” Science agrees that friendship does have its benefits.

growing body of research has shown that having friends can improve your physical and mental health and even reduce your risk of mortality. In a study, published earlier this year in the journal Child Development, a team of researchers found that close childhood friendships can play a significant role in a person’s mental health well into adulthood.

Timothy Smith, a fellow of the American Psychological Association and a professor of psychology at Brigham Young University, says the findings are significant, as they show long-term data that our social relationships influence our mental health. More specifically, he tells Yahoo Lifestyle, “the research shows that teens who have a close friend, rather than needing to seek approval from many people, are happier as young adults.”

The study tracked 169 racially, ethnically, and socioeconomically diverse adolescent participants over 10 years, starting with when they were 15 years old and ending when they were 25. Each year, the participants were asked about their closest friendships and participated in assessments that explored their anxiety, depression, self-worth, and social acceptance. Their closest friends were also interviewed.

The findings showed that those with higher-quality best friendships tended to improve in several aspects of mental health over time, including lower social anxiety, an increased sense of self-worth, and fewer symptoms of depression by the time they reached age 25. Higher-quality friendships were those with some degree of attachment, support, and the trust needed for intimate exchange.

“It seems like close friendship at age 15 sort of ‘set in motion’ these long-term gains,” says Rachel Narr, the lead author of the study and a doctoral student in psychology at the University of Virginia. “That could be true for a variety of reasons, potentially including the fact that the teenage years are when the first major non-family relationships and attachments are formed.”

Alexis Conason, a clinical psychologist based in New York City isn’t surprised by the findings. “Meaningful friendships early in life build the foundation for mental well-being down the road,” she tells Yahoo Lifestyle.

Friendship might also help you live longer. For example, a 2010 study published in the journal PLOS, showed that people with strong social relationships increased their odds of survival over a certain time period by 50 percent. Researchers analyzed 148 individual studies that examined the link between friendship and mortality, with more than 308,000 participants in total. They found that the stronger the social relationships, the better the odds of survival, regardless of age, gender, health status, and cause of death.

In similar research, one study published in the journal of the American Heart Association suggests that people with fewer friends tend to die sooner after having a heart attack than people with strong social relationships. The study, which examined 3,400 heart attack survivors ages 18 to 55, found that participants lacking strong social support were more likely to smoke, abuse alcohol, and have high blood pressure, diabetes, and depression — which are all heart attack risk factors.

In another study, people with ovarian cancer who had lots of social support had much lower levels of a protein linked to more aggressive cancers. This made their chemotherapy treatments more effective and increased their odds of survival.

And, again, with respect to mental health, a study that examined flood victims and the onset of post-traumatic stress disorder (PTSD) showed that recovery from PTSD was significantly associated with social support. The study assessed PTSD in 321 flood victims 13 to 14 years after they were first diagnosed to measure the prevalence rate of PTSD among them and identify the association between social support and their recovery from PTSD. On the follow-up, only 51 were diagnosed as still having PTSD, which correlated with those without the presence of close social bonds.

Researchers cannot say for sure what the exact mechanism is between better health and close social relationships, but they have some ideas. In the study that looked at adolescent friendships and mental health, Narr says that having someone during that important, formative time period who you can trust, and who trusts you, really alters your expectations for yourself and other people, in a positive way. “Many studies have shown that having more positive expectations for the world tends to make you happier — and there are definitely links between a positive social environment and depression and anxiety,” she says.

People more often engage in exercise and eat nutritious diets when they live with others than when they live alone, according to Smith. Additionally, people in strong social networks receive greater support when they show signs of illness or experience health conditions.

“Giving and receiving love in close relationships, buffers against stress and improves neuroendocrine functioning,” Smith adds. People with strong relationships enjoy improved cardiovascular health, immune functioning, and many other health benefits.

Shasta Nelson, a friendship expert and author of Frientimacy: How to Deepen Friendships for Lifelong Health and Happiness defines a friendship as: a mutual relationship between two people that is satisfying, safe, and where both people feel seen. “If you don’t have all three, then you don’t have a healthy friendship,” she explains.

If you’re lacking in the friend department, experts warn, don’t be shy. It’s never too late to make one. “If you’re waiting around for a potential friend to say hello first, you might be waiting a while,” says Theo Orozco, a life coach who specializes in helping introverts step out of their comfort zones. Making the first move doesn’t have to be complicated. She says a simple smile, “hi,” or friendly question could be the start of an interesting conversation.

“Human beings are social creatures,” says Conason. “We yearn for connection with others, and when we are able to achieve this connection, to feel seen and understood by another, it fulfills the psyche.”

In other words, embrace your friends. Your health will thank you.

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