Numerous studies have looked at life expectancy and marital status. Even after social and economic factors (such as poverty and education) are factored in, it seems that married people (particularly men) live longer than their unmarried peers.
Marriage (and to some extent long term defacto relationships) have been routinely linked to lower rates of heart disease, reduced risk of accident and suicide and even (in some instances) a decreased likelihood of cancer and stroke.
People who never marry generally seem to be the least healthy. Those who are widowed or divorced also show increased mortality rates, particularly in the couple of years directly after losing their spouse. This is particularly true for those in their 20s and 30s.
What could cause this?
Perhaps researchers could be confusing cause and effect. Maybe the old adage “all the good ones are taken” is true? Research has certainly shown that those people who don’t marry have comparatively low levels of education and are more likely to be out of work. Perhaps healthier and more successful people make more attractive spouses?
This could explain the difference between the health of married and never-married people, but it doesn’t explain why people who used to be married are less healthy.
So it probably comes down to stress.
One possibility for stress reduction in marriage comes with a division of labour – in a couple, there are two people to share the work of gaining income, two people to divide costs and to share household chores etc.
Another reduction may come from the psychological benefits of having a spouse – someone to listen to your problems and provide regular sex. Perhaps marriage even strengthens the desire to look after yourself – encouraging you to keep in shape and work out to remain attractive.
A partner may also help to nurse you through minor illnesses, reducing long term health effects.
One of the strongest factors appears to be the presence of a social network. This extends beyond the spouse, and takes in friends, relatives and the entire community. Where people have strong networks, research has shown a reduction in cardiovascular disease and accidental/suicidal death. Marriage may help to provide such a network.
Certainly, as the proportion of people in one marital status group rise, the health benefits increase also. If you never marry, it is better to live in a community with a large number of other singles, than in one where everyone you know is coupled up.
The social stigma of being different to the norm seems to cause the problem. This even extends to children born out of wedlock. Again, people born to unmarried parents, particularly those who never marry have poorer health than their counterparts.
A note of warning though. An unhappy marriage may cause increased stress, so probably isn’t going to help.Thus any potential benefits can only come from marrying the right (type of) person.
Note: There is a huge amount of literature available on this topic, from all around the world. This is but a small subsection.
Ben-Shlomo Y, Smith GD, Shipley M, Marmot MG. (1993) Magnitude and causes of mortality differences between married and unmarried men. J Epidemiol Community Health. 47(3):200-5.
Ebrahim S,Wannamethee G, McCallum A, Walker M,Shaper AG. (1995) Marital status, change in marital status, and mortality in middle-aged British men. Am J Epidemiol.;142(8):834-42.
Hu YR, Goldman N. (1990) Mortality differentials by marital status: an international comparison. Demography. 27(2):233-50.
Janlert U, Asplund K, Weinehall L, Orth-Gomer K, Unden AL.(1992) Men who never married. A socio-medical study in northern Sweden. Arctic Med Res.;51(2):72-80.
Kaplan RM, Kronick RG.(2006) Marital status and longevity in the United States population. J Epidemiol Community Health.;60(9):760-5.
Kawachi I, Colditz GA, Ascherio A, Rimm EB, Giovannucci E, Stampfer MJ, Willett WC. (1996) A prospective study of social networks in relation to total mortality and cardiovascular disease in men in the USA. J Epidemiol Community Health.;50(3):245-51.
Mendes de Leon CF, Appels AW, Otten FW, Schouten EG. (1992) Risk of mortality and coronary heart disease by marital status in middle-aged men in The Netherlands. Int J Epidemiol.;21(3):460-6.
Modin B. (2003) Born out of wedlock and never married–it breaks a man’s heart. Soc Sci Med.;57(3):487-501.
Nilsson PM, Nilsson JA, Ostergren PO, Berglund G. (2005) Social mobility, marital status, and mortality risk in an adult life course perspective: the Malmo Preventive Project. Scand J Public Health. 33(6):412-23.