Good news for coffee drinkers: A recent study from the NIH-AARP Diet and Health Study finds that coffee drinkers live longer. Credit: Wikipedia.
Recently, I told you about research indicating that tipsy people might get more benefit from the caffeine than sober imbibers will. This is useful after-hours information, but of limited day-to-day value.
For coffee drinkers, there is little that is more delightful than starting the day with a cup of freshly brewed coffee. Starbucks knows this and has brilliantly converted that morning pleasure into a megabusiness. We ignore those studies that come out now and then with their irritating findings that coffee can increase risk of heart disease by raising LDL (bad cholesterol) levels and increasing blood pressure, or that some of the substances in the complex brew are linked to cancer. But now, there is a study that will be welcomed by baristas and their customers everywhere.
A study published in this week’s New England Journal of Medicine gets right to the bottom line: Coffee drinkers tend to live longer.
Neal Freedman of the National Cancer Institute led the study of 400,000 people, making it the largest study done on the issue and is part of the National Institutes of Health and AARP Diet and Health Study.
As the data were analyzed, initial indicators were that coffee drinkers were likely to die at any time. However, when researchers accounted for other diet and lifestyle habits that are known to shorten lifespans—smoking, alcohol and red meat consumption, lack of exercise, etc.—a clear pattern of living longer emerged.
According to a news story, the NIH-AARP study began in 1995 and involved AARP members between 50-71 years old in select states and cities. The study eliminated people with heart disease, stroke or cancer and those whose diets were either too high or too low in calories. Of the 400,000+ participants, about 10 percent did not drink coffee. About 15,000 drank six or more cups per day, but most people reported drinking two or three. About two-thirds of the coffee drinkers preferred caffeinated coffee; the rest drank decaf.
Here is the bottom line: Men who drank two to three cups of coffee per day were 10 percent less likely to die at any age, and women were 13 percent less likely. Even a single cup of coffee per day made a difference for six percent for men and 5 percent for women. The largest effect was for women who drank four or five cups per day. Their risk of death was reduced by 16 percent. People who were healthy to begin with benefited the most.
The story reports that coffee drinkers are “less likely to die from heart or respiratory disease, stroke, diabetes, injuries, accidents or infections. No effect was seen on cancer death risk, though.”
It’s important to note that the study does not prove causality, only correlation. It does not provide the link between coffee and lifespan, but shows that there is a statistically meaningful relationship. However, the story points out that the large number of subjects, more than a decade of follow-up and a statistically significant number of deaths to compare, means this is probably pretty good evidence. There are other studies looking at things like the effect of coffee on inflammation and insulin resistance.
Freedman declines to guess at how much extra life drinking coffee could buy, partly because of the effects of smoking, which affects longevity at all ages. Also, the story points out that adding sugar, cream, etc. can mitigate coffee’s benefits.
I’m ok with that. I’m happy to know that I may be able to enjoy a good cup of coffee for a good long time.