Does staying single lead to an early grave?(2)

Solitude sickness

Another reason for single people's greater risk of mortality, said Du, was the attendant mental stresses that came with being alone.

Du said that those who remained single past the socially-defined norm for the ages of marriage were at greater risk of depression and anxiety.

"Although emotional problems are quite common among young people, being single for a prolonged period of time, and constantly trying to suppress the emotions that come from being lonely, can lead problems such as depression, anxiety, and insomnia," said Du. "Perhaps most worrying is the fact that many single people who have been alone for a long time say that they've lost the ability to love and forgotten how to deal with another person in a relationship."

Du said that many of his patients have told him that the source of their mental anguish is their solitude, which has led them to feel as if they are unable to love.

"I think this inability to love is a mental problem, which manifests itself in the fear of intimacy," said Du. "Even for those who voluntarily choose to be single, the pressures exerted by society to be in a relationship can be difficult to deal with."

In addition to psychological problems that can arise from remaining single, some doctors said that the lack of sexual intercourse could lead to physical health problems.

Guo Jun, director of the andrology (male reproductive health) department at Xiyuan Hospital under China Academy of Traditional Chinese Medicine, said that long-term abstinence as a result of being single could have a detrimental effect on health.

"Living without sex for a long time can lead to prostate problems," said Guo.

For women, it is a similar story. In a report published in the Nandu Daily in 2010, Guan Ting, a gynecologist and obstetrician at Guangzhou Military Hospital, said women who do not give birth are at higher risk of breast cancer and cervical cancer.

A question of lifestyle

A number of people have spoken out against the sweeping generalizations being made as a result of the study. While the study may point to a correlation between being single and living an unhealthy lifestyle, the inference that being single necessarily leads to an unhealthy lifestyle is incorrect, critics say.

Such objections are supported by David Roelfs, assistant professor of sociology at the University of Louisville and the study's lead author.

In an interview with NBC News in 2011, Roelfs took pains to point out that the study was about "probabilities, not certainties," and that it didn't look into the underlying reasons for the higher mortality risk for singles.

"The last thing we want is for some single person to say 'Oh my God, I'm going to die young," said Roelfs in the report.

"I think the claim [that being single results in an earlier death] is completely absurd," said Liu Longhui, a 29-year-old financial worker who has been single for more than three years.

"I lead a very healthy lifestyle, far healthier than many married couples I know."

Liu said that single people frequently have more free time and flexibility, giving them the opportunity to look after themselves properly and to improve themselves.

"Instead of accompanying a girl on a shopping trip, I can spend that time exercising and getting fit," said Liu.

"Of course, it comes down to what you do with that free time. If you spend all your free time at home playing computer games and eating junk food, then probably you will die younger."

Liu also made mention of the fact that not all married couples were happy. He said that two of his married friends quarreled every day, leading to stress and diminishing their quality of life.

A 2011 study published in the Journal of Health and Social Behavior indicated that the mortality gap between singles and people in married couples is closing.

"I think the view that single people are less healthy is not always true," said Wang Gudao, a professor at Anhui University of Chinese Medicine.

Wang said that whether single or not, as long as people adhered to the four cornerstones for a healthy heart advocated by World Health Organization - diet, regular physical activity, no tobacco, and a supportive psycho-social environment, they would most likely have long life expectancy.

"If you choose to be single because you find it makes you happier, then it makes sense to remain single," said Wang. "If you're forced to be single and you have to endure it for a long time, then it's possible that this might lead to health problems."