Being lonely takes years off of your life and is as dangerous as smoking or being fat, according to scientists.
But accepting the fact you may end up in a care home when you get into your 70s and 80s could ward off loneliness.
Researchers claimed having wise expectations about the normality of getting older would help people adapt to it.
Their study, which quizzed 30 people living in sheltered housing in San Diego, revealed the various coping mechanisms the residents used, which also included being proactive about finding companions or turning to religion or spirituality.
Eighty-five per cent of the people who were questioned, aged between 67 and 92, admitted they felt moderate to severe loneliness.
Lead author Dr Dilip Jeste, of the University of California, San Diego, said: ‘Loneliness rivals smoking and obesity in its impact on shortening longevity.
‘It is paramount we address the well-being of our seniors. They are friends, parents and grandparents of the younger generations.’
Approximately 42.6million adults over 45 in the US say they are lonely. One quarter of the population also lives alone.
And around 5 per cent of adults living in the UK feel lonely ‘often’ or ‘always, data from the Office for National Statistics shows.
Loneliness is thought of mainly as a mental problem but, if someone feels alone for a long time, it can cause knock-on damage to physical health as well.
It drives up levels of the stress hormone, cortisol, which can lead to unhealthy swelling inside the body, weight gain and insulin resistance which may cause diabetes.
Possible health problems include high blood pressure, difficulty sleeping, depression, and a higher risk of dementia as the brain withers if it isn’t stimulated.
In the study, Dr Jeste and his team analysed the physical and mental health of the participants using the UCLA Loneliness Scale.
The 20-item questionnaire is a frequently referenced and acknowledged academic measure used to gauge loneliness.
A score of 28 or less equals no or low feelings of loneliness. Forty-three or higher indicates high levels of loneliness.
The researchers found that 63 per cent of volunteers felt moderately lonely and 22 per cent felt highly alone.
Fifteen per cent felt only slightly lonely or did not feel lonely at all, according to the results published in the journal Aging and Mental Health.
One elderly person quoted in the study said: ‘I’m very silent, and I would be away from everybody and everything.
‘I can think of periods where I felt lonely, and it was a sense of not being attached, not having very much meaning, and not feeling very hopeful.’
Some common themes for why people felt alone were found, with the greatest factor being age-related loss of loved ones and friends.
Another factor was that many felt disoriented living in housing for retired people and felt their lives had become hopeless or purposeless.
However, the scientists found a number of coping strategies which elderly people used to fight feelings of being lonely.
One was to accept the ageing process and recognise that there were some positive changes to getting older and adapting to the ‘new normal’.
Others felt that helping others made them feel less lonely.
One woman said: ‘Another technique that I had for years, if you’re feeling lonely then go out and do something for somebody else… That’s proactive.’
A third way of coping was to seek the company of others, with some saying that feeling lonely was a choice which could be rejected.
A final common theme was that there were features of their sheltered housing which helped to reduce isolation.
These included a putting green, pool tables and use of a library and computers.
Some also said they enjoyed being alone and did not feel the need of other peoples’ company.
And others said their faith and spirituality helped them to cope with losses of loved ones and prevent loneliness.
Two-thirds of those who took part in the research were women but the researchers did not say that thee lack of men taking part influenced their results.
But of the limitations they did identify, the researchers said that those who took part were mostly well-educated and and were of middle or high income.
They also accepted that the results may not generalise to people living in other parts of the country or those living in their own or rented homes.
They added that a more in-depth investigation into people’s personal history might have given a greater understanding of their perspective of loneliness.