Lawrence Solomon
National Post
September 4, 2004

When coffee first came to Europe from Constantinople in 1615, Viennese priests warned it was "the drink of infidels." The warnings in recent times have come from scientists, pseudo-scientists, and governments.

For most of the last half century, coffee was a health pariah, suspected of causing everything from breast, colon and pancreatic cancer to heart disease, infertility and birth defects. To get to the bottom of often wild speculation based on the flimsiest of evidence, the medical world swung into action in the 1980s and 1990s, with many of the world’s leading scientists and research bodies investigating coffee’s effects on health.

Today, some 19,000 studies later, it is clear that most past concerns didn’t amount to a hill of beans. The great preponderance of evidence has lain to rest virtually all coffee-related health concerns.

One of the first major studies to implicate coffee consumption with heart disease was the Western Electric Study into the diet of almost 2,000 men in the late 1950s. The study found that those who drank three cups or less of decaffeinated coffee per day has less heart disease than those who drank regular coffee. Then a 1970s study, the Boston Collaborative Drug Surveillance Program, reinforced coffee-related fears when it found that patients who had been hospitalized for heart attacks were likelier to have been coffee drinkers.

Early studies also linked coffee to cancers. In 1971, U.S. scientists writing in the British medical journal, The Lancet, speculated that "Coffee drinking may cause cancer of the bladder." In 1981, Harvard researchers published in The New England Journal of Medicine an "unexpected" finding that coffee could account for most pancreatic cancers, with two cups of coffee a day doubling and five cups tripling the risk.

One by one, the early studies have been discredited. To the credit of the Harvard researchers, they themselves disproved their own findings five years after they issued their first alarm, by failing to confirm their own findings in a repeat study.

Interpretations of the early heart studies also came to be known as deficient: They failed to notice, for example, that coffee drinkers tended to be smokers. The well designed heart studies that followed, such as the Scottish Heart Health Study that looked at 11,000 men and women between age 40 and 59 who drank up to 21 cups of coffee per day, told an altogether different story: The higher the coffee consumption, the lower the chances of heart disease or death, this seven-year study reported in the late 1990s in the Journal of Epidemiology and Community Health.

In 2000, the Archives of Internal Medicine published an even larger study, taking place over almost three decades, of 200,000 Finnish men and women. Among the women, the more coffee they drank, the less likely they were to die from any cause. Among the men, the study found that those who consumed "moderate" amounts of coffee, defined as four to seven cups per day, faced the lowest risk of death from heart disease. Men who consumed no coffee, or more than seven cups a day, were at the greatest risk. Among high-risk populations – those who also smoked, had high cholesterol, elevated blood pressure, or previous heart attacks – coffee drinkers remained less likely to die of heart disease than coffee abstainers.

Other large and extensive studies also dismissed the early link found between coffee consumption and heart trouble. A 1996 study of more than 121,000 female nurses found that, after researchers adjusted for cigarette smoking, even high levels of coffee drinking didn’t increase heart attack risk. An article in The Archives of Internal Medicine of a study that followed a group of male medical school graduates for 33 years found that drinking one cup of coffee a day led to no significant increase in the risk of developing high blood pressure. A 10-year study of more than 85,000 women found that those who drank six or more cups of coffee a day were no more likely to have a heart attack than women who drank one or two cups. Even among arrhythmias, or patients with irregular heartbeats, drinking as much as five cups of coffee a day mattered not at all. In five arrhythmia studies, there were no increases in the frequency or likelihood of skipped beats.

Coffee has also received a clean bill of health in women’s health, which became a concern after a study in the late 1970s by surgeon John Minton suggested a link between Fibrocystic Breast Disease (FBD) and caffeine. Because most women experience FBD symptoms such as pain and tenderness, many women became alarmed. Their alarm heightened as other researchers, citing the FBD study, soon speculated that caffeine consumption could lead to breast cancer.

Subsequent studies, including a 1986 study of more than 3,400 women conducted at the National Cancer Institute, found no relationship between FBD and caffeine intake. By 1992, leading researchers concluded that "contrary to the suggestion of Minton, we found no [breast cancer] risk associated with drinking coffee or any other caffeine-containing beverage. To our knowledge, no large-scale epidemiological study has ever done so."

Birth defects? After a 1980 study force-fed caffeine to rats via stomach tubes, the U.S. Food and Drug Administration issued an advisory warning pregnant women to avoid caffeine. Follow-up studies in the 1980s and 1990s failed to confirm the early birth defect scare.

Osteoporosis? A 1997 study in the American Journal of Clinical Nutrition found no association between lifetime caffeine consumption and bone changes or osteoporosis risk in postmenopausal women, whether they were low, moderate or high caffeine consumers.

Ovarian cancer? Bladder cancer? No and no. No, too, to numerous other hunches based on what amounted to the following observation: People who developed ailments had been drinking coffee, the most consumed beverage in the world.

At the same time that study after study dismissed health concerns related to coffee consumption, numerous studies, to the surprise of medical researchers, indicated health benefits in drinking coffee. Earlier this year, a study at the Harvard School of Public Health of more than 126,000 people found that men who drank more than six eight-ounce cups of caffeinated coffee per day lowered their risk of type 2 diabetes by about half, and women by nearly 30%, relative to coffee abstainers. Decaf drinkers enjoyed half the benefits of regular coffee drinkers, with men showing a 25% risk reduction and women 15%. Tea drinking, meanwhile, showed no effect on diabetes.

The Harvard results are consistent with a 2004 study of 13,000 Finns that found that the risk of type 2 diabetes decreases in proportion to coffee consumption, and with a 2000 study of 17,000 Dutch adults that found that drinking seven cups of coffee or more a day cut the risk of developing type 2 diabetes while drinking two cups or less did not.

The coffee data distilled by researchers also points to health benefits in Parkinson’s, a disease that especially strikes men. In a 2000 study of 8,000 Japanese men, the Journal of the American Medical Association reported that non-drinkers had five times the risk of contracting Parkinson’s as those who drank four to five cups of coffee a day. Eight other studies likewise found that coffee protected against Parkinson’s.

Coffee may thwart other diseases, too. Studies in the United States, Japan and Italy showed that drinking three to four cups of coffee a day was associated with an 80% reduction in risk for cirrhosis of the liver, compared with drinking no coffee at all. A 10-year study of 45,000 men found that two to three cups of coffee a day reduced the risk of developing gallstones by 40%., and four or more cups reduced the risk by 45%. U.S. and Italian studies found that three or more cups of coffee a day led to decreased prevalence of asthma. Psychological Science, the journal of the American Psychological Society, reported that caffeine boosted memory in elderly people who drank one or two cups of coffee in the morning by raising calcium levels in their brain cells. Coffee has also been found to improve long-term memory as well as psychomotor skills.

Also promising, coffee may hold widespread benefits as a cancer fighter, according to a 2003 study from the Institute for Food Chemistry at the University of Munster in Germany. For the first time, researchers identified a specific, highly active anti-cancer compound in coffee, methylpyridinium, not found in significant amounts in other foods and beverages, whose anti-cancer activity had been unknown, according to Dr. Thomas Hofmann, professor and head of the Institute.

More generally, researchers have been jolted by coffee’s anti-oxidant properties, as seen in a study conducted by the Faculty of Medicine at the University of Oslo. The study examined 61 adults, and relied upon a nationwide survey of 2672 Norwegian adults, to determine which food groups provide the body with its Vitamin C, carotene, and other anti-oxidants, substances believed to reduce the risk of major chronic degenerative diseases. To the authors’ surprise, they discovered that coffee provided two-thirds of the total of all dietary anti-oxidants, followed by fruits, tea, wine, cereals and vegetables.

The stage is now set for coffee to become repositioned as a health food, or even a health elixir, particularly after a 2001 study by the Cancer Epidemiology Training Program at the University of California at Los Angeles School of Public Health indicated that coffee could lower the risk of prostate cancer, and a more a recent Brazilian study of 750 patients awaiting vasectomy, presented to the American Society for Reproductive Medicine conference in Texas, indicated that coffee drinkers have better sperm motility. Scientists are now investigating the use of coffee in solving fertility problems. Other medical doctors, at the periphery of medicine, prescribe coffee enemas to treat pancreatic cancer, an incurable disease. Their apparent success in keeping patients alive has prompted America’s National Cancer Institute to give US$1.4 million over five years to researchers at Columbia University’s College of Physicians and Surgeons to test the regimen.

Coffee, a drink once held in great suspicion, still believed by some to stunt one’s growth, may soon be touted to be a general tonic, as the pendulum swings from considering it to be a drink of the devil to the other extreme, as a brew that can cure whatever ails you.

Until more evidence comes in, the agnostic view of Vanderbilt University’s Institute for Coffee Studies seems easiest to swallow: "Overall, the research shows that coffee is far more healthful than it is harmful," says the Institute’s Tomas DePaulis. "For most people, very little bad comes from drinking it, but a lot of good."

Lawrence Solomon is executive director of Urban Renaissance Institute and Consumer Policy Institute, divisions of Energy Probe Research Foundation. He is also a director of GreenBeanery.ca, a non-profit merchant of green coffee beans.