(May 20, 2011) Over the last few years, I have been struck by the avalanche of studies indicating that coffee consumption promotes human health. Just last week came news from Swedish researchers in the peer-reviewed Breast Cancer Research that showed a significant decrease in breast cancers among post-menopausal women who were avid coffee drinkers. Last month came news from Harvard researchers in the peer-reviewed Journal of the National Cancer Institute that males who drink lots of coffee contract fewer prostate cancers, and especially fewer lethal prostate cancers, than those who don’t drink coffee.
So what does Health Canada, an agency that sees danger in just about everything, say about the startling benefits of coffee consumption? To find out, I searched for “Health Canada” and “coffee” and landed on its “Caffeine” fact sheet, part of a series called “It’s Your Health.”
The fact sheet purports to follow the “best scientific evidence available.” Yet it had not one reference to any study showing health benefits from coffee consumption, and didn’t even hint at potential benefits, apart from stating that “For healthy adults, a small amount of caffeine may have positive effects, such as increased alertness or ability to concentrate.” Even this grudging acknowledgement was immediately countered by warnings that “some people are more sensitive to caffeine. For them, a small amount could cause insomnia, headaches, irritability and nervousness.”
To the disservice of millions of Canadians who might want balanced and factual information from their government’s health website, Health Canada treats coffee and caffeine as unambiguously dangerous substances that need to be controlled. It cites numerous potential “adverse health effects” — everything from cardiovascular illnesses to general toxicity to cancer. And to reduce the presumed danger, it recommends limiting consumption to “no more than 400 mg of caffeine per day, the equivalent of about three eight-ounce (237 ml) cups of brewed coffee” for a healthy male. Unhealthy males, presumably, should drink less, as should women of child-rearing age, who are advised to limit themselves to “a little over two eight-ounce (237 ml) cups of coffee.” This despite studies that show drinking coffee stimulates milk production in lactating mothers without changing the composition of the milk. Health Canada claims to be monitoring the science to help it make informed recommendations as more is learned.
Here’s what Health Canada should learn from the latest scientific literature. For a male, healthy or not, to optimize his chance of avoiding prostate cancer — the most common cancer in men — he should drink at least six cups of coffee per day. Drink that much, says the Harvard School of Public Health study of 48,000 American males, and his chances of contracting prostate cancer drop by 18%. Better still, his chances of surviving prostate cancer increase by 60%. Put another way, men who don’t drink coffee are two-and-a-half times likelier to die from prostate cancer than men who drink six or more cups a day. Those who drink fewer cups will still reduce their risk of dying, just by a lesser amount — each cup of coffee per day reduces the prostate cancer death rate by about 6%.
Health Canada should also learn what coffee can do for women, particularly for those in the vulnerable 50-to-74-year range, which Sweden’s Karolinska Institute investigated. Because Swedes are among the world’s most voracious coffee drinkers — three cups per day on average — Karolinska researchers embarked on an exhaustive study involving some 6000 women. Those who drank six or more cups of coffee per day — the highest consumption category it examined — were less likely to contract breast cancer, the most common cancer in women, when compared to women in the lowest coffee consumption category (women who drank no coffee or one cup per day).
Among breast cancers, 30% are “ER-negative,” an especially dangerous type that is less amenable to therapy and more often leads to death. The six-or-more-cup-a-day women were 57% less likely to get ER-negative breast cancer than one or zero cup drinkers (the three-to-five cup drinkers were 40% less likely and the two-to three cuppers 23% less likely).
Other studies show coffee drinkers to live longer and to be less likely to suffer from colon cancer, strokes, Alzheimer’s, Type-2 diabetes, and Cirrhosis of the liver among major health concerns, as well as migraines, asthma and bronchitis among often less threatening conditions. In contrast to the overwhelming number of encouraging studies, vanishingly few point to dangers.
Where did Health Canada get its negative view of coffee and caffeine? By following links on its website, I found its source, a report entitled Effects of caffeine on human health. This 2003 document — a literature review — did find some reasons to have some suspicions, such as when rats consumed caffeine by the vat-full. In contrast, this literature review found no reason to recommend coffee to humans concerned about breast or prostate cancer, or the onset of Alzheimer’s. Who wrote this see-only-evil assessment of coffee and caffeine? Five researchers, who doubtless mean well but do harm, from Health Canada.
Lawrence Solomon is executive director of Urban Renaissance Institute and founder of Green Beanery, a non-profit coffee company.