Drinking coffee lowers suicide risk by as much as 50 percent in both men and women, according to a new study from Harvard School of Public Health.
Coffee doesn't stimulate the brain, but acts like an antidepressant by accelerating the production of neurotransmitters such as serotonin, dopamine, and noradrenaline, according to the researchers.
The study was based on three large reports conducted in the U.S. on the subject. Scientists specifically looked at beverages that had caffeine.
"Unlike previous investigations, we were able to assess association of consumption of caffeinated and non-caffeinated beverages, and we identify caffeine as the most likely candidate of any putative protective effect of coffee," said Michel Lucas from Harvard School of Public Health and lead author of the study in a news release.
There are many conflicting reports on the effects of coffee. A study published in the New England Journal of Medicine says that coffee consumption can't be linked to risk of heart attacks or stroke while another study says that coffee is positively related to increased risk of heart attacks.
Another study claims that coffee consumption is related to a significantly lower incidence of Parkinson's disease (PD). Coffee intake has also been linked to reduced risk of common type of skin cancer and increased odds of living for a long time.
The current study looked into caffeine consumption of over 200,000 men and women between 1988 and 2008. All the study participants were enrolled in either one of the three large epidemiological studies.
Researchers looked for all sources of caffeine from the participants' diet such as soft drinks and chocolates. During the study period, there were about 277 suicide deaths in the study cohort.
The study found a link between coffee consumption and lower suicide risk. Researchers, however, don't recommend changes in coffee consumption based on this study.
"Overall, our results suggest that there is little further benefit for consumption above 2-3 cups/day or 400 mg of caffeine/day," the authors wrote.
Previous research from HSPH had shown that drinking more than four cups of coffee doesn't affect health adversely.
As mentioned earlier, do not increase coffee consumption based on this study findings. There are many products that contain high levels of caffeine and you might already be getting all the caffeine that you need to maintain a healthy diet.