The percolating coffee debate

We see coffee shops everywhere. And getting a cup of coffee is almost like paying for one regular meal in a food court. Is coffee good or bad for one’s health? The debate is still percolating and health experts can’t give any straightforward or categorical answer to this question. Arguments can swing extremely to one side or the other like a pendulum.

Prof. Ana Baylin and her colleagues from Harvard’s School of Public Health, in a study published in Epidemiology several years ago, found an association between coffee consumption and a higher incidence of first, nonfatal heart attacks. Most people in the study reported drinking two to three cups of coffee per day.

However, in another study published in the Journal of the American Medical Association, Prof. Wolfgang Winkelmayer and his colleagues from the Brigham and Women’s Hospital in Boston, Massachusetts, found no direct association between caffeine consumption and the development of high blood pressure or heart disease. This was a robust study in 155,594 women who had participated in the Nurses’ Health Studies (NHS) I and II.

Turning point

A Harvard study in 2008 became a turning point regarding the ffect of caffeine on health, which involved an impressively long 20-year follow-up of over 130,000 participants from the NHS and the Health Professionals Follow-up Study.

Evaluating the long-term outcome of those who consumed up to six cups of coffee per day (containing around 100 mg caffeine per 8 oz cup), the researchers found no link with increased deaths in either men or women from any cause, including deaths from cancer, or from cardiovascular diseases (CVDs).

According to Prof. Rob van Dam of the Department of Nutrition, Harvard School of Public Health, who was one of the study authors, their findings validated the results of other smaller studies published previously. “For the general population, the evidence suggests that coffee drinking doesn’t have any serious detrimental health effects,” he said.

Lifestyle change

He added that rather than think of coffee drinking as the culprit for any health problem, people should focus on other forms of lifestyle change such as smoking and physical inactivity or sedentary living, which tended to be more common among heavy coffee drinkers.

So the previous link between coffee drinking and CVDs was simply due to the association of coffee drinking with other unhealthy lifestyle practices, but not due to caffeine ingestion itself.

A further boost to a potential health benefit of caffeine was the Kaiser Permanente study presented at the American Heart Association convention in March 2010, which showed that coffee drinkers were less likely to be hospitalized for cardiac arrhythmia or heart rhythm disturbances. This was based on findings from more than 100,000 health plan holders who drank one to three cups of coffee and had a lower risk than nondrinkers, regardless of other risk factors.

Moderate thinking

Another American study reported in 2012 showed that drinking coffee in moderation appeared to reduce the risk of heart failure.

How about for women? A study monitoring over 30,000 women for 10 years, reported in March 2011 by the Karolinska Institutet in Stockholm, Sweden, found that those who drank more than one cup of coffee per day appeared to have a 22- to 25-percent lower risk of stroke, as compared to nondrinkers. The researchers wrote that “low or no coffee consumption was associated with an increased risk of stroke in women.” This finding was consistent even after considering other possible risk factors like smoking, alcohol, body mass index, diabetes and high blood pressure.

This finding was similar to that of an earlier US study, published in 2009, which followed up on the outcome in around 80,000 women from the NHS. The researchers reported a 20-percent lower risk of stroke among coffee drinkers. According to these researchers, the relative risk of stroke went down as coffee consumption went up.

However, this finding has to be tempered by a health advisory from the Harvard Health newsletter which warned that while moderate coffee consumption (three to four cups a day) may be linked to a lower risk for stroke among regular coffee drinkers, infrequent coffee consumers may have an increased risk of a stroke just after drinking a cup of coffee.

Daily coffee intake of 200 mg

What is the bottom line about coffee and what advice can we give almost every other Filipino who’s seduced by the aromatic scent of a freshly brewed coffee? I think it’s best to limit one’s coffee intake to one cup, at most two, a day, which would mean a caffeine consumption of less than 200 mg per day. This level has not been associated with increased cardiovascular risk even in slow caffeine metabolizers.

How about decaffeinated coffee? It’s another controversy with some reports suggesting some adverse effects. I don’t think shifting to decaf would really solve the problem.

Just enjoy your cup or two of regular coffee daily.

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