It brings better mental and physical health, reducing the chance of premature death by 15 per cent, according to major studies in seven European countries.
And the longer a marriage lasts the more the rewards accumulate – the only catch being that the relationship has to be loving and supportive.
John Gallacher, a Cardiff University academic who reviewed the European studies, said the happily married were more likely to eat healthily, have more friends and take better care of each other.
‘Marriage and other forms of partnership can be placed along a sliding scale of commitment, with greater commitment conferring greater benefit,’ he added.
‘That marriage generally indicates a deeper commitment might explain why marriage is associated with better mental health outcomes than cohabiting. Cohabiting relationships tend to be less enduring. The most widely accepted explanation is that being in a committed relationship means better social support is available.
‘Commitment seems to provide networks of supportive and helpful relationships, beginning with the spouse or partner, leading to more healthy lifestyles and better emotional and physical health.’
The research findings were reviewed by Dr Gallacher and his doctor son David in an editorial for the British Medical Journal.
Many married couples are often unaware of the advantages, they said, but a study of one billion ‘person years’ in seven countries found husbands and wives were 10-15 per cent less likely to die prematurely than the population as a whole.
Analysis of 148 studies of social relationships found their legal status and the amount of emotional support involved were linked to death rates, with marriage coming out on top. There is no evidence available to judge the health of people in civil partnerships, said Dr Gallacher.
Evidence shows the optimal time for men to marry seems to be after the age of 25, whereas for women it is between 19 and 25 years, he said, adding: ‘In terms of physical health, men benefit more from being in a relationship than women, but in terms of mental health women benefit more than men.
‘The physical health premium for men is likely to be caused by their partner’s positive influence on lifestyle.
‘The mental health bonus for women may be due to a greater emphasis on the importance of the relationship in women.’
The advantages keep growing over time, with studies followed up for 30 years showing longer relationships are linked to better mental health.
'The difference in mortality rates in favour of marriage also increases with age', said Dr Gallacher.
But he warned that difficult and strained relationships were bad for mental health, and being single was better than being in a strained relationship.
‘The take home message is simple. Exclusive and supportive relationships confer substantial mental and physical health benefits that grow over time,’ he added.
Although failure of a relationship can harm health, that is an argument for avoiding a bad relationship rather than not getting into a relationship at all.
‘On balance, it is probably worth making the effort,’ he said.
Last year, a World Health Organisation study revealed marriage could reduce the risk of anxiety and depression and those who tied the knot were much less likely to suffer the blues than those who stayed single.
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