For many women, the mood-elevating effects of a cup of coffee may be more than fleeting.
A new study shows that women who regularly drink coffee — the fully caffeinated kind — have a 20 percent lower risk of depression than nondrinkers. Decaf, soft drinks, chocolate, tea and other sources of caffeine did not offer the same protection against depression, possibly because of their lower levels of caffeine, the authors say.
More research is needed, he said, and “a very high level of caffeine can increase anxiety” and insomnia, potentially reversing any mood-lifting effects.
A link between caffeine intake and depression had been suspected for years. Previous research reported that the risk of suicide decreases with increasing coffee consumption. Between 1996 and 2006, the women provided detailed information every two years on their caffeine intake, depression risk factors and overall health, including their weight, their use of hormones and their levels of exercise and smoking. Over all, women who regularly drank coffee had a lower risk of depression — about 20 percent — than the women who abstained, and the risk was dose-dependent. The researchers aren’t sure why caffeine might keep depression at bay. In an editor’s note that accompanied the study, Dr. Seth A. Berkowitz called the research “an important contribution because it is, to my knowledge, the first large-scale study of coffee consumption to evaluate a mental health outcome in women.” The latest study looked only at women drinking as much as four to six cups of coffee a day, and not women drinking greater amounts.