Four Or More Cups Of Coffee A Day May Help Prevent Gout

Coffee is a habit for more than 50 percent of Americans, who drink, on average, two cups per day. This widely consumed beverage is regularly investigated and debated for its impact on health conditions from breast cancer to heart disease. Among its complex effects on the body, coffee or its components have been linked to lower insulin and uric acid levels on a short-term basis or cross-sectionally. These and other mechanisms suggest that coffee consumption may affect the risk of gout, the most prevalent inflammatory arthritis in adult males.

To examine how coffee consumption might aggravate or protect against this common and excruciatingly painful condition, researchers at the Arthritis Research Centre of Canada, University of British Columbia in Canada, Brigham and Women’s Hospital, Harvard Medical School, and Harvard School of Public Health in Boston conducted a prospective study on 45,869 men over age 40 with no history of gout at baseline. Over 12 years of follow-up, Hyon K. Choi, MD, DrPH, and his associates evaluated the relationship between the intake of coffee and the incidence of gout in this high risk population. Their findings, featured in the June 2007 issue of Arthritis & Rheumatism, provide compelling evidence that drinking four or more cups of coffee a day dramatically reduces the risk of gout for men.

Subjects were drawn from an ongoing study of some 50,000 male health professionals, 91 percent white, who were between 40 and 75 years of age in 1986 when the project was initiated. To assess coffee and total caffeine intake, Dr. Choi and his team used a food-frequency questionnaire, updated every four years. Participants chose from nine frequency responses - ranging from never to two to four cups per week to 6 or more per day - to record their average consumption of coffee, decaffeinated coffee, tea, and other caffeine-containing comestibles, such as cola and chocolate.

Through another questionnaire, the researchers documented 757 newly diagnosed cases meeting the American College of Rheumatology criteria for gout during the follow-up period. Then, they determined the relative risk of incident gout for long-term coffee drinkers divided into four groups - less than one cup per day, one to three cups per day, four to five cups per day, and 6 or more cups per day - as well as for regular drinkers of decaffeinated coffee, tea, and other caffeinated beverages. They also evaluated the impact of other risk factors for gout - body mass index, history of hypertension, alcohol use, and a diet high in red meat and high-fat dairy foods among them - on the association between coffee consumption and gout among the study participants.

Most significantly, the data revealed that the risk for developing gout decreased with increasing coffee consumption. The risk of gout was 40 percent lower for men who drank four to five cups a day and 59 percent lower for men who drank 6 or more cups a day than for men who never drank coffee. There was also a modest inverse association with decaffeinated coffee consumption. These findings were independent of all other risk factors for gout. Tea drinking and total caffeine intake were both shown to have no effect on the incidence of gout among the subjects. On the mechanism of these findings, Dr. Choi speculates that components of coffee other than caffeine may be responsible for the beverage’s gout-prevention benefits. Among the possibilities, coffee contains the phenol chlorogenic acid, a strong antioxidant.

While not prescribing four or more cups a day, this study can help individuals make an informed choice regarding coffee consumption. “Our findings are most directly generalizable to men age 40 years and older, the most gout-prevalent population, with no history of gout,” Dr. Choi notes. “Given the potential influence of female hormones on the risk of gout in women and an increased role of dietary impact on uric acid levels among patients with existing gout, prospective studies of these populations would be valuable.”

Higher Coffee Consumption Associated With Lower Liver Cancer Risk

A new large, prospective population-based study confirms an inverse relationship between coffee consumption and liver cancer risk. The study also found that higher levels of gamma-glutamyltransferase (GGT) in the blood were associated with an increased risk of developing the disease. These findings are published in the July issue of Hepatology, a journal published by John Wiley & Sons on behalf of the American Association for the Study of Liver Diseases (AASLD). The article and an accompanying editorial are also available online at Wiley Interscience.

Researchers led by Gang Hu at the University of Helsinki set out to examine the associations between coffee consumption and serum GGT with the risk of liver cancer in a large prospective cohort. Residents of Finland drink more coffee per capita than the Japanese, Americans, Italians, and other Europeans, so Hu and colleagues studied 60,323 Finnish participants ages 25 to 74 who were cancer-free at baseline. The Finns were included in seven independent cross-sectional population surveys conducted between 1972 and 2002 and followed up through June 2006.

The participants completed a mail-in questionnaire about their medical history, socioeconomic factors and dietary and lifestyle habits. For a subset of participants, clinical data was available, including serum levels of GGT. Data on subsequent cancer diagnoses was collected from the country-wide Finnish Cancer Registry.

Based on their answers to the question: "How many cups of coffee do you drink daily?" the participants were divided into five categories: 0-1 cup, 2-3 cups, 4-5 cups, 6-7 cups, and 8 or more cups per day. After a median follow-up period of 19.3 years, 128 participants were diagnosed with liver cancer.

The researchers noted a significant inverse association between coffee drinking and the risk of primary liver cancer. They found that the multivariable hazards ratio of liver cancer dropped for each group that drank more coffee. It fell from 1.00, to .66, to .44, to .38 to .32 respectively. "The biological mechanisms behind the association of coffee consumption with the risk of liver cancer are not known," the authors point out.

They also found that high levels of serum GGT were associated with an increased risk of liver cancer. The hazard ratio of liver cancer for the highest vs. lowest quartile of serum GGT was 3.13. "Nevertheless," they report, "the inverse association between coffee consumption and the risk of liver cancer was consistent in the subjects at any level of serum GGT."

An accompanying editorial by Carlo La Vecchia of Milan says that Hu’s new study solidly confirms the inverse relationship between coffee drinking and liver cancer risk, though we still don’t know if it is causal. "Furthermore, the study by Hu et al. provides original and important quantitative evidence that the levels of GGT are related to subsequent incidence of liver cancer, with an overall relative risk of 2.3," he says.

La Vecchia notes, however, that, "It remains difficult, however, to translate the inverse relation between coffee drinking and liver cancer risk observed in epidemiological studies into potential implications for prevention of liver cancer by increasing coffee consumption."