Coffee's mood-boosting effect that many people swear by is apparently `more longer lasting' than they realize --- with US researchers having found that four cups of coffee a day can reduce the risk of depression in women by 20 percent!

According to the findings of a study led by Alberto Ascherio of Boston's Harvard School of Public Health, caffeine is the world's most frequently-used stimulant for the central nervous system, and regular intake of coffee boosts a person's energy and enhances overall well-being, both in the short term as well as in the long run.

On the basis of a study of 50,000 women - averagely aged 63 years - who participated in a health-related observation of nurses in 1976, the researchers found that there is a 20 percent lower chance of depression among women who consumed four or more cups of coffee per day; and a 15 percent lower risk in those who drank 2-3 cups.

Despite the fact that the researchers compared the `coffee consumption' and `depression risk' in women alone, the results seemingly translate to men too; with some other studies having found a similar effect of coffee on men.

Highlighting that the findings of the new study "support a possible protective effect of caffeine, mainly from coffee consumption, on risk of depression," one of the researchers, Dr Michel Lucas, stressed on the need of further investigations "to determine whether usual caffeinated coffee consumption may contribute to prevention or treatment of depression"!