How Crying Can Make You Healthier

It makes nine out of 10 people feel better, reduces stress, and may help to keep the body healthy. It's also free, available to almost everyone, and has no known side effects, other than wet tissues, red eyes and runny makeup. Crying may not be a blockbuster drug, but the latest research suggests it's highly effective at healing, and that it improves the mood of 88.8 per cent of weepers, with only 8.4 per cent feeling worse. So beneficial is it that the researchers suggest there may be a case for inducing crying in those who find it difficult to let go.

But while almost all of us shed emotional tears at some time -- at least 47 times a year for women, and seven for men -- exactly why we cry, and much about what happens when we do, remains a mystery. For crying, a uniquely human form of emotional expression, to have survived evolution, it should have a practical purpose and give some kind of survival advantage. Laughter and anger are both well known to have advantages. Laughter, for example, has been shown to promote healing, increase blood flow, reduce levels of stress hormones, boost the immune system and produce more disease-fighting compounds.

But what of crying? Emotional tears come from the same tear glands that produce the fluid that forms a protective film over the eyeballs to keep them free of irritants, and which also releases extra fluid when the eye becomes irritated, or is invaded by a foreign body.

A clue to the purpose of crying may lie in the experimental finding that emotional tears contain different compounds from regular eye watering, such as that triggered by chopping onions.

The phenomenon supports the so-called recovery theory, that emotional tears, and their contents, may be a way of getting the body back in balance after a stressful event. "I have suggested that we may feel better after crying because we are literally crying it out. Chemicals that build up during emotional stress may be removed in our tears when we cry,'' says William Frey, professor of pharmaceutics at the University of Minnesota. "Because unalleviated stress can increase our risk for heart attack and damage certain areas of our brain, the human ability to cry has survival value.''

Other evidence backs up the theory. It's been shown that tears associated with emotion have higher levels of some proteins, and of manganese and potassium, and hormones, including prolactin than mere eye watering. Manganese is an essential nutrient, and too little can lead to slowed blood clotting, skin problems, and lowered cholesterol levels. Too much can also cause health problems. Potassium is involved in nerve working, muscle control and blood pressure.

Prolactin is a hormone involved in stress and plays a role in the immune system and other body functions. Its involvement in tears may help to explain why women cry more than men. Women have more prolactin than men, and levels rise during pregnancy, when the frequency of crying among women also increases.

There have also been some claims that crying can reduce pain, although there has been little research into this area. The phenomenon, if verified, may be an indirect effect -- in that crying may trigger physical contact with another individual and touch has been linked to improved wellbeing.

A counter theory is that crying doesn't so much help the body recover from whatever triggered the tears, but that it increases arousal to encourage behaviours to see off the threat. In support of this theory, some research shows that skin sensitivity increases during and after crying, and that breathing deepens. Some argue that crying could perform both these functions: "It is possible that crying is both an arousing distress signal and a means to restore psychological and physiological balance," say researchers at the University of South Florida. Others suggest that emotional tears signal distress and encourage group behaviour, as well as improve social support and inhibit aggression.