One of life's simple pleasures just got a little sweeter. After years of waffling research on coffee and health, even some fear that java might raise the risk of heart disease, a big study finds the opposite: Coffee drinkers are a little more likely to live longer. Regular or decaf doesn't matter.
The study of 400,000 people is the largest ever done on the issue, and the results should reassure any coffee lovers who think it's a guilty pleasure that may do harm.
``Our study suggests that's really not the case,'' said lead researcher Neal Freedman of the National Cancer Institute. ``There may actually be a modest benefit of coffee drinking.''
No one knows why. Coffee contains a thousand things that can affect health, from helpful antioxidants to tiny amounts of substances linked to cancer. The most widely studied ingredient _ caffeine _ didn't play a role in the new study's results.
It's not that earlier studies were wrong. There is evidence that coffee can raise LDL, or bad cholesterol, and blood pressure at least short-term, and those in turn can raise the risk of heart disease.
Even in the new study, it first seemed that coffee drinkers were more likely to die at any given time. But they also tended to smoke, drink more alcohol, eat more red meat and exercise less than non-coffee-drinkers. Once researchers took those things into account, a clear pattern emerged: Each cup of coffee per day nudged up the chances of living longer.
The study was done by the National Institutes of Health and AARP, an organization that advocates for people 50 years and older.
The results are published in Thursday's New England Journal of Medicine.
Careful, though _ this doesn't prove that coffee makes people live longer, only that the two seem related. Like most studies on diet and health, this one was based strictly on observing people's habits and resulting health. So it can't prove cause and effect.
But with so many people, more than a decade of follow-up and enough deaths to compare, ``this is probably the best evidence we have'' and are likely to get, said Dr. Frank Hu of the Harvard School of Public Health. He had no role in this study but helped lead a previous one that also found coffee beneficial.
The new one began in 1995 and involved AARP members ages 50 to 71 in California, Florida, Louisiana, New Jersey, North Carolina, Pennsylvania and Atlanta and Detroit. People who already had heart disease, a stroke or cancer weren't included. Neither were folks at diet extremes _ too many or too few calories per day.
The rest gave information on coffee drinking once, at the start of the study. ``People are fairly consistent in their coffee drinking over their lifetime,'' so the single measure shouldn't be a big limitation, Freedman said.
Of the 402,260 participants, about 42,000 drank no coffee. About 15,000 drank six cups or more a day. Most people had two or three.
By 2008, about 52,000 of them had died. Compared to those who drank no coffee, men who had two or three cups a day were 10 percent less likely to die at any age. For women, it was 13 percent.
Even a single cup a day seemed to lower risk a little: 6 percent in men and 5 percent in women. The strongest effect was in women who had four or five cups a day _ a 16 percent lower risk of death.
None of these are big numbers, though, and Freedman can't say how much extra life coffee might buy.
``I really can't calculate that,'' especially because smoking is a key factor that affects longevity at every age, he said.
Coffee drinkers were less likely to die from heart or respiratory disease, stroke, diabetes, injuries, accidents or infections. No effect was seen on cancer death risk, though.
Other research ties coffee drinking to lower levels of markers for inflammation and insulin resistance. Researchers also considered that people in poor health might refrain from drinking coffee and whether their abstention could bias the results. But the study excluded people with cancer and heart disease _ the most common health problems _ to minimize this chance. Also, the strongest benefits of coffee drinking were seen in people who were healthiest when the study began.
About two-thirds of study participants drank regular coffee, and the rest, decaf. The type of coffee made no difference in the results. (AP)
<한글 기사>
하루에 커피 한잔! 당신의 수명은?
커피를 매일 마시는 것이 노인들에게 사망위험을 다소 줄 여주는 효과가 있다는 연구결과가 나왔다.
미국 국립암연구소(NCI)의 닐 프리드먼(Neal Freedman) 박사는 커피를 하루 한 잔 이상 마시는 노인은 커피를 마시지 않는 노인에 비해 사망위험이 5-16% 낮은 것으로 조사되었다고 밝혔다.
프리드먼 박사는 50-71세의 남녀 40만2천260명을 대상으로 13년에 걸쳐 실시한 조사분석 결과, 커피를 하루 2-3잔 마시는 사람은 마시지 않는 사람에 비해 사망위험이 남성은 10%, 여성은 13% 낮은 것으로 나타났다고 밝혔다.
커피를 매일 한 잔만 마셔도 사망위험이 남성은 6%, 여성은 5% 낮아지는 것으로 나타났다.
커피를 하루 4-5잔 마시는 여성은 사망위험 감소효과가 16%로 가장 높았다.
커피를 마시는 사람은 심장병, 호흡기질환, 뇌졸중, 당뇨병, 부상, 사고, 감염에 의한 사망률이 낮았다. 그러나 암으로 인한 사망위험은 낮아지지 않았다.
다만 커피를 마시는 사람은 마시지 않는 사람에 비해 담배를 피우거나 음주량이 많거나 적색육을 많이 먹고 운동을 적게 할 가능성이 높은 것으로 나타났는데 이 결 과는 이러한 요인들을 모두 고려한 것이라고 프리드먼 박사는 설명했다.
조사 시작 때 심장병, 뇌졸중, 암 병력이 있는 사람과 하루 칼로리 섭취량이 너 무 많거나 적은 사람은 제외됐다.
커피가 사망위험 감소와 연관이 있는 이유는 제시되지 않았다.
커피에는 건강에 도움이 되는 항산화물질에서 극소량이지만 암과 연관이 있는 물질에 이르기까지 1천여 가지의 성분이 들어있다.
다만 주성분인 카페인은 연관이 없는 것으로 보인다. 카페인 커피를 마시는 사람이나 디카페인 커피를 즐기는 사람이나 이러한 효과에는 차이가 없었기 때문이다.
이 연구결과는 의학전문지 '뉴 잉글랜드 저널 오브 메디신(New England Journal of Medicine)' 최신호(5월16일자)에 실렸다.
