Women who like their daily coffee fix are in luck.
In a new study, women who drank two to three cups of caffeinated coffee a day were 15 percent less likely to experience depression; those who drank four cups or more, 20 percent less likely.
Published online September 26 in the journal Archives of Internal Medicine, the Harvard Medical School study looked at the coffee habits and moods of more than 50,000 female nurses over a period of 24 years.
The researchers aren't clear why coffee has this effect but they believe that caffeine may alter the brain's chemistry. Decaffeinated coffee had no mood-boosting effect in the study.
In May, another Harvard study found that drinking coffee, either decaf or regular, can ward off the risk of prostate cancer. In March, another study published in the US's Journal of the American Heart Association found that drinking at least one cup of coffee a day could keep stroke at bay.
Still the researchers say it is too soon to start recommending too much coffee. The US-based Mayo Clinic recommends no more than two to four cups a day, since more than that can cause insomnia, upset stomach and anxiety.