Several cups of coffee per dayor 400 mg of caffeine reduces suicide risk by 50 percent

Drinking several cups of coffee daily appears to reduce the risk of suicide in men and women by about 50 percent, according to a new study by researchers at the Harvard School of Public Health (HSPH).

The authors reviewed data from three large U.S. studies and found that the risk of suicide for adults who drank two to four cups of caffeinated coffee per day was about half that of those who drank decaffeinated coffee or very little or no coffee.

Caffeine not only stimulates the central nervous system but may act as a mild antidepressant by boosting production of certain neurotransmitters in the brain, including serotonin, dopamine, and noradrenaline. This could explain the lower risk of depression among coffee drinkers that had been found in past epidemiological studies, the researchers reported.

In spite of the findings, the authors do not recommend that depressed adults increase caffeine consumption, because most individuals adjust their caffeine intake to an optimal level for them and an increase could result in unpleasant side effects. “Overall, our results suggest that there is little further benefit for consu – mption above two to three cups/day or 400 mg of caffeine/day,” the authors wrote.

The World Journal of Biological Psychiatry – Coffee, caffeine, and risk of completed suicide: Results from three prospective cohorts of American adults

Objective.To evaluate the association between coffee and caffeine consumption and suicide risk in three large-scale cohorts of US men and women. Methods. We accessed data of 43,599 men enrolled in the Health Professionals Follow-up Study (HPFS, 1988–2008), 73,820 women in the Nurses’ Health Study (NHS, 1992–2008), and 91,005 women in the NHS II (1993–2007). Consumption of caffeine, coffee, and decaffeinated coffee, was assessed every 4 years by validated food-frequency questionnaires. Deaths from suicide were determined by physician review of death certificates. Multivariate adjusted relative risks (RRs) were estimated with Cox proportional hazard models. Cohort specific RRs were pooled using random-effect models. Results. We documented 277 deaths from suicide. Compared to those consuming ≤ 1 cup/week of caffeinated coffee (If you liked this article, please give it a quick review on ycombinator or StumbleUpon. Thanks