Medicine: Coffee Nerves

Is there cancer in the cup?

More than half the population over age ten gulps down coffee at an average rate of two cups a day. To coffee lovers the black brew is an elixir that soothes frazzled nerves, gives the mind a lift at exam time, spells drop-in hospitality to the housewife. Yet in recent years coffee has been tentatively tied to various afflictions, including diabetes, heart attack, and cancer of the colon, urinary tract and stomach. Last week Harvard University researchers announced a statistical link between coffee and cancer of the pancreas. The pancreas produces enzymes vital to digestion and the hormone insulin for sugar metabolism. Pancreatic cancer claims 22,000 lives a year. It is the fifth largest cause of cancer death in the U.S., behind cancer of the lungs, colon, breast and prostate. It is also virtually incurable; fewer than 2% of patients survive five years after diagnosis.

Epidemiologist Brian MacMahon and his team stumbled upon the association while studying the effects of smoking and alcohol in 369 patients with pancreatic cancer who had been admitted to eleven New England hospitals between 1974 and 1979. The patients were questioned in detail about their use of tobacco and alcohol and incidentally about their drinking of tea and coffee. Their answers were then compared with those obtained from a control group of 644 patients hospitalized for different forms of cancer and for some nonmalignant diseases as well.

The study, reported in the New England Journal of Medicine, found no link between pancreatic cancer and use of cigars, pipe tobacco, alcohol or tea. However, it did show that the chances of having the disease were slightly increased in the case of cigarette smokers. But researchers were surprised to find a notable rise in pancreatic cancer among coffee drinkers. Compared with its occurrence in patients who did not drink coffee at all, the disease was two times as frequent among people who drank one or two cups a day and three times as frequent among those drinking three or more cups. What ingredient of coffee might account for the higher risk is a mystery. Caffeine itself seems to be exonerated because heavy tea drinkers showed no higher incidence of cancer.

There have been hints of a link between coffee and pancreatic cancer before. The Harvard team points to a study ten years ago that indicated pancreatic cancer occurred more frequently in countries where coffee consumption was high. Mormons and Seventh-day Adventists, who generally do not use coffee (or cigarettes), have low rates of the disease. There has also been a case of simultaneous cancers in a husband and wife—a rare occurrence. Perhaps significantly, both added extra coffee syrup to their ground coffee before percolating it. The researchers speculate that half the 24,000 new cases of pancreatic cancer each year might be the result of coffee drinking.