A large study involving nearly 51,000 women found that drinking four or more cups of coffee a day appears to lower the long-term risk of depression. Researchers from the Harvard School of Public Health followed participants in the long-running Nurses’ Health Study to see what effect coffee would have on the risk of depression.
At the study’s outset, none of the women reported being depressed, and none were taking antidepressants. As the study progressed, results indicated that women who drank four or more cups of coffee daily had a 20 percent lower risk of depression than those who drank one cup or less daily. Those who consumed two to three cups had a 15 percent lower risk of depression.
Too much caffeine can jangle the nerves, boost anxiety levels, and contribute to other health risks, but caffeine does have well-known short-term positive effects on mood – it can provide an energy boost and increase alertness. Until now, however, little has been known about its possible long-term effects on mood.
The study was published in the September 26 issue of the Archives of Internal Medicine.