Friendship keeps you healthy – more than any other relationship

Do I have the right nutrition? Do enough sport and get enough sleep? A fancy car or the latest fashion? What is it that makes humans healthy and happy? Deep down everyone probably suspects that it’s primarily the immaterial things that enrich us. The most famous research project on this topic comes from the renowned Harvard University. The Grant Study examined what’s perceived as joy, over an 80-year period. Over this time span, researchers looked at the participants’ health trajectories and their future lives, including their successes and failures in their careers and personal lives.

The finding: «Our social relationships and how happy we are in them have a strong influence on our health,» says study leader Robert Waldinger, a professor of psychiatry at Harvard Medical School. «It’s good to take care of your body, but taking care of relationships is also a vital way to take care of yourself.»

To celebrate this self-care, we took a closer look at the latest scientific findings from happiness and friendship research. The good news? After reading this, the next time you hang out with your mates will be extra special.

The lowdown: friends improve your health

Science journalist Lydia Denworth, who wrote a book on the science of friendship, is amazed at how much social isolation affects our immune systems. When you’re lonely, this can make your white blood cells change their behaviour, leading to more inflammation and a weakened immune response.

New research also shows that good friends and good physical health may be even more closely linked than previously assumed. This is according to a study recently published in the journal Society for Personality and Social Psychology. The study involved observing more than 4,000 people for three weeks who used smartphones/watches to note positive and negative experiences with their closest social relationships. At the same time, they rated their blood pressure, heart rate, stress factor and coping ability. The result? More positive experiences in social relationships were generally associated with better coping, lower stress and lower systolic blood pressure (i.e., blood pressure spikes during stress).

Socially integrated people also tend to live longer and healthier lives, have a lower risk of high blood pressure and better self-healing abilities.

Live longer and better

Researchers at Brigham Young University in Utah have documented the health of more than 300,000 people over eight years. They analysed data from 148 previously published longitudinal studies that measured the frequency of human interactions. The result: social relationships lead to a lower mortality rate and a longer life.

In contrast, the research team also noted how low social interaction overall compares to known risk factors. It appears to be equivalent to smoking about 15 cigarettes a day, alcoholism and is more harmful than physical inactivity or obesity. It was also striking that the positive influence of relatives, children and partners was significantly lower than that of friendships.

By the way, the healthy «Friends Effect» has nothing to do with age. According to the study leader, «Friendly relationships offer a certain protection for all age groups – from teens to pensioners.»

Become happier and mentally stable

Interestingly, happiness and positive mental health have a kind of network effect – they spread through relationships. You may have heard of the idea that all people around the world are six or fewer social connections away from each other. Happiness is similarly interconnected. A study conducted at Harvard with 5,000 people over 20 years found: a person’s sense of happiness tends to spread over three degrees. So if one person is happy it still affects a friend of a friend of a friend.

In contrast, sadness doesn’t seem to have this ripple effect. A study by the University of Warwick found that feelings of happiness and a positive mental state spread among people in groups, while depression did not. People who maintain many and good friendships also have a higher pain threshold and are more mentally resilient. This is according to a study conducted at Oxford University.

Those who have an extensive social network produce more endorphins, or happiness hormones. Study leader Katerina Johnson commented, «These findings are also interesting because recent research suggests that the endorphin system may be disrupted in mental health problems such as depression. This may be one of the reasons that depressed people often withdraw socially.»

Her verdict? «It’s not just our study that suggests that the quality of our social relationships affect our physical as well as mental health and life expectancy. Therefore, it’s important to understand which neurobiological mechanisms are involved. A lack of interactions is the most overlooked factor contributing to the deteriorating health of our modern society.»