The study, published Tuesday, analyzed data from roughly 51,000 older women who participated in the Nurses’ Health Study from 1996 until 2006.
The women had an average age of 63, and none were depressed when they enrolled in the study.
During that period, 2,607 cases of depression were diagnosed; women who drank two or more cups of coffee a day, however, reported 20 percent fewer cases of depression — and the risk of depression fell with each additional cup of coffee she drank.
This is one of the first major studies to look to this relationship, lead author Michel Lucas, PhD, RD, epidemiologist/nutritionist at Harvard School of Public Health in Boston, Massachusetts, told Medscape Medical News.
In the 10-year study of more than 50,000 women, investigators found that compared with those who drank one cup or less of caffeinated coffee per week, with those who drank two to three cups per day, which had a 15 percent decreased risk for depression.
Participants who drank four cups or more had a 20 percent decreased risk.