3 to 4 Cups of Coffee Daily Provide Most Health Benefits

Here's news of a study that's worth reading. And you might want to pour yourself a hot cup of coffee while doing so.

Working off data collected from more than 200 meta-analyses, researchers found that moderate coffee drinking provided many health benefits and that any shortcomings from consumption were outweighed by the positive effects. The findings were published recently in the journal The BMJ, stating the optimal amount of coffee consumption being roughly three to four cups per day.

"The researchers found that drinking three cups of coffee a day was associated with the greatest benefit in terms of cardiovascular disease, coronary heart disease, and stroke, when compared with not drinking coffee," according to a BMJ article on the study. "Consumption at this level was associated with a 19% lower risk of mortality from cardiovascular disease ... a 16% lower risk of mortality from coronary heart disease ... and a 30% lower risk of stroke mortality." 

The exception to those who would benefit are pregnant women; they are advised to limit their caffeine intake to 200 milligrams per day, as to avoid any increased risk of miscarriage.

The study, conducted by researchers from the University of Southampton, incorporated the work of 201 meta-analyses of observational studies as well as 17 more of "interventional research." And while drinking "more than three cups a day was not associated with harm," states the article, "the beneficial effects were less pronounced, the researchers found."

"We don’t know entirely why it has these benefits, but the evidence suggests there is a synergy between caffeine and the antioxidants in the coffee,” said Robin Poole, public health specialist at the University of Southampton and the paper’s lead author. “People who are already drinking moderate amounts of coffee aren’t likely to be harmed by coffee drinking," he added, "apart from in pregnancy and the small increased risk of fractures among women. The bottom line is that we suggest it can be a good part of a healthy diet.”

In addition, consumption of large amounts of coffee appeared to confer protections regarding some cancers as compared to those who drank much less. Java drinkers demonstrated a "lower risk of prostate cancer, endometrial cancer, melanoma, oral cancer, leukemia, non-melanoma skin cancer, and liver cancer." Researchers also cited "a beneficial effect on liver and gastrointestinal outcomes."

While women benefitted less than men when it came to stroke mortality, they benefitted more in terms of cardiovascular disease mortality and reduced risk of coronary heart disease.

A couple of notable points: Researchers did not define the exact amount of coffee that constituted one cup, or whether the coffee consumed was instant, espresso or whether the beans producing the beverage were roasted. 

They also restricted their focus to coffee's effects on health, while ignoring how caffeine affects consumers. They also chose to disregard consumption of sugar, milk and creamers, since only a segment of consumers drink black coffee. Therefore, how these sugars and fats contribute to the subjects' overall health is also not known.