In a society which seems to have become increasingly "individualised", the risk of social isolation has almost certainly increased. That is particularly bad news if you are a man. There is a stack of evidence that being socially isolated damages men's health. But there are also clues as to how this damage might be counteracted.
In the latest US research, thousands of men and women were asked about their social contacts including spouses, relatives, friends and religious or other groups.
They then underwent blood tests to enable researchers to measure the concentration in their blood of markers indicating inflammation. Inflammation is thought to enable white blood cells to attach themselves to the sides of veins and arteries, leading to atherosclerosis with an elevated risk of heart trouble.
What the study found was that the most socially isolated men had the highest inflammation and the most socially connected men had the lowest. In women, social isolation or connection made no difference.
European researchers have also found that deaths from stroke and heart disease occur at a higher rate in unmarried men than in married men. Again, women being married or unmarried seems to make little difference.
One British study even found that over a particular seven-year period single men were at greater risk of dying than smokers. This led one researcher to suggest that single men who smoke should get married quickly to counteract the health dangers of smoking. By the way, this wouldn't work for very long because the lifetime risk from smoking is far higher than it is over a seven-year period.
So what's going on? Researchers in the US study suggested that socially isolated men probably have less healthy lifestyles than those who are socially connected. They also suggested that people who are isolated are more likely to be stressed or depressed than those who are not. Stress and depression also seem to play a role in ill health.
But why are the findings for women different? The researchers suggested that the quality of women's relationships could be the vital factor here. Even socially isolated women, in such contacts as they have, are more likely to confide in someone than are single men, they suggested.
Confiding in someone may make all the difference to their levels of stress or depression, they suggest, and this makes women healthier. Married men, researchers point out, can confide in their wives. Single men often confide in no one.
There is also an old Swedish study which found people with social networks were less likely to develop dementia in old age than people who were isolated.
Here, too, the quality of relationships seemed to be the vital factor. It wasn't necessary to see people every day to get this protective effect. The important thing was being in touch with people and feeling you were part of a network rather than being surrounded by people all the time.
These findings about the quality of relationships provide a clue as to how socially isolated men can protect their health: if there is someone you can confide in, even if you don't see them often, confide in them. Keeping in touch with relatives, friends and acquaintances can be crucial to the quality of your life. So can involvement with activities, organisations and so on.
There is something about us that needs contact with others even if we find other people a nuisance. Some people get around this by keeping in touch on the internet, people with whom they may never meet but to whom they can tell their hopes, fears, worries, views and memories. I have never seen a study of the mental health benefits of such electronic contact but I suspect it has a value. The key finding from this research, especially for men, is: keep in touch, it could save your life.
Padraig O'Morain is a journalist and counsellor accredited by the Irish Association for Counselling and Psychotherapy.