Coffee Reduces Depression & Suicide---But Why?
Fall 2011: Archives of Internal Medicine publishes a study, which in turn, is picked up by media outlets everywhere. The proclamation: Coffee reduces depression in women!
That’s old news.
What’s new, however, are the data---and the continuation of a longstanding study of women from the Nurses’ Health Study. Researchers found that over a 10-year period, women who drank coffee had less self-reported depression. That is 2 to 3 cups per day was associated with a 15% reduced risk of depression, compared with drinking 1 cup or less. Drinking 4 or more cups increased that benefit---and reduced the risk of depression by 20%.1
For the record, decaffeinated coffee did not have any impact on the risk of depression.
Fifteen years ago, the Archives of Internal Medicine published a similar study. They looked at 86,625 women between the ages of 34 and 59 over a 10-year period. The period of analysis was from 1980 to 1990---and the endpoint was suicide---a very severe outcome associated with depression. In this study, women who drank 2 to 3 cups of coffee a day were 66% less likely to commit suicide, compared with non-coffee drinkers.2
Looking at this data side by side, I was curious about why the researchers were more interested in suicide than depression during the earlier analysis. Depression in the recent study was defined as feeling self-reported depression or being on antidepressants. I suspect---and it’s just a hypothesis—that the widespread availability of antidepressants AND access to coffee in a community setting in places like Starbucks has allowed people to address their depression more effectively than in the past. Good pharmacology and a communal coffee culture has helped ease our pain, be it chemical, existential, or circumstantial.
The idea that coffee helps people be less depressed is intuitively understood by the hundreds of millions of people who enjoy it every day. We are more productive, alert, engaged, and energized for the task at hand. Yes, it is largely due to the caffeine---in fact, 80% of all caffeine consumed is consumed in coffee. But I believe that there’s more: There is the power of community. Drinking coffee together. Then going out for a walk---and enjoying the gifts of the season.
Happy fall, coffee drinkers…as the days get shorter and cooler, join me in drinking lots of hot coffee. Let’s stay happy!
1. Kawachi et al. A prospective study of coffee drinking and suicide in women. Arch Intern Med. 1996;156:521-5.
2. Lucas M et al. Coffee, caffeine, and risk of depression among women. Arch Intern Med. 2011;171:1571-78.