By Richard Lenti
It’s one of the most widely consumed beverages in the world. And for many, the day can’t begin without it. But that cup of coffee may be doing more than giving you a caffeine boost to jump start the day — it may also help you live a longer, according to the author of a 2012 study published in The New England Journal of Medicine.
“We asked participants at the start of the study, “How do you feel?,”asking them to rate their health. It turns out that self-reported health is quite a good predictor of subsequent mortality,” Dr. Neal Freedman of the National Cancer Institute said in an interview with the Journal of Caffeine Research.
“We found that the people who were reporting excellent health status—the people who said they had very good or excellent health—they were the ones where coffee was having the strongest association.”
Using data from the National Institutes of Health–AARP Diet and Health Study, researchers followed over 400,000 men and women between the ages of 50 and 71 for about 12 years.
Contrary to studies that have shown an association between coffee consumption and heart disease, what Freedman and his team found was a clear correlation between coffee and longevity,
They also observed that people who drank the most coffee tended to have the greatest health benefits; that people who drank two or three cups of coffee a day were 10 percent to 15 percent less likely to die an early death.
“What we found was that over the course of follow-up, there was an inverse association between coffee drinking and the risk of death overall,” said Freedman.
“The association was similar for men and women, and tended to get stronger as participants drank more coffee, though the result was very similar for those who drank two or three cups per day and those who drank more than that. The top category we had was six or more cups per day.”
Researchers noted an inverse association between coffee drinking and most major causes of death, with the exception of cancer. And that people in the study who said they had very good or excellent health were the ones where coffee was having the strongest positive association.
But there was a down side to all that coffee consumption: poor health behaviors.
Coffee drinkers were found more likely to smoke cigarettes and consume more than three alcoholic drinks per day. They consumed more red meat, tended to have a lower level of education, were less likely to engage in vigorous physical activity, and reported lower levels of consumption of fruits, vegetables and white meat.
“In our study, the effect of smoking actually got a little worse after adjustment for coffee drinking.” said Freedman. “Now, it was a very modest effect, and smoking is a very strong risk factor for death. But this result suggests that, among the smokers, maybe their risk of death would have been a little higher if many of them had not also been drinking coffee.”
“However, it is very important to stress that the negative health effects of smoking have a far greater magnitude than any possible benefit of coffee,” he added.
Freedman noted that there were inherent limitations to the study including the fact that coffee consumption was assessed by self-report at a single time point and did not reflect long-term patterns of consumption.
Another problem was that distinction between persons who drank caffeinated coffee and those who drank decaffeinated coffee was subject to misclassification.
“My concern is that our study does not really inform very well on caffeine itself,” said Freedman. “Our study really is on coffee, and we have quite poor assessment of the different components and compounds in coffee. Thus, from our data, we cannot really say which aspect of coffee might be important for the association.”
With that in mind, Freedman points out that coffee contains more than 1000 compounds that might affect the risk of death. He adds that it is also a rich source of antioxidants and other bioactive compounds, and that studies have shown inverse associations between coffee consumption and serum biomarkers of inflammation and insulin resistance.
“This large prospective cohort study showed significant inverse associations of coffee consumption with deaths from all causes and specifically with deaths due to heart disease, respiratory disease, stroke, injuries and accidents, diabetes, and infections.”
“Our results provide reassurance with respect to the concern that coffee drinking might adversely affect health.”