Caffeinated beverages may benefit some people who are at high-risk for liver disease

May 19 2004

According to new research presented today at Digestive Disease Week, drinking caffeinated beverages may benefit some people who are at high-risk for liver disease. Conversely, a study by researchers from India found that soda drinkers, who represent a huge percentage of the American population, may actually have an increased risk of developing esophageal cancer. DDW is the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery.

“This research supports the widespread medical recommendations for healthy eating,” said Lee Kaplan, M.D., Ph.D., of Massachusetts General Hospital. “The relationships between diet and disease that these investigators have seen are intriguing and should stimulate further exploration in this important area. It is even more apparent that lifestyle and dietary choices made during youth can have a significant impact on health later in life.”

Coffee and Caffeine Consumption Protect Against Liver Injury in the United States Population Researchers from the National Institute of Diabetes and Digestive and Kidney Disease of the National Institutes of Health are reporting that among people who are at high risk for liver problems, coffee drinking and consumption of other caffeinated beverages may reduce risk of liver disease.

The national, population-based study was conducted among 5,944 adult participants of the third U.S. National Health and Nutrition Examination Survey (NHANES III) who were at high risk for liver injury (due to excessive alcohol consumption, hepatitis B or C, iron overload, obesity, or impaired glucose metabolism). Participants were asked about consumption of caffeine-containing coffee, tea and soft drinks. The study found an inverse correlation between coffee and caffeine consumption and liver injury, which was classified by abnormal serum alanine aminotransferase (ALT) activity and was seen in approximately 8.7 percent of this high-risk population.

In analyses both unadjusted and adjusted for age, sex, ethnicity and cigarette smoking, the prevalence of liver injury declined with increasing coffee drinking and caffeine consumption, though the protective effect was greater for caffeine intake. The correlation was consistent across subgroups when defined by individual risk factors for liver injury, as well as when applied to persons without impaired liver function. “There is surprisingly little evidence-based information on the influence of diet and nutrition on the course and severity of chronic liver disease,” said James Everhart, M.D., M.P.H., co- author of the study. “These results warrant further study.”

Rise of Esophageal Adenocarcinoma in USA is Temporally Associated with the Rise in Carbonated Soft Drink Consumption Researchers at Tata Memorial Hospital in India have found a strong correlation between the rise in per capita consumption of carbonated soft drinks (CSD) in the past 20 years and the increasing rates of esophageal cancer (ACE) in the United States.

Based on available data on diet changes in America from the U.S. Department of Agriculture, per capita consumption of CSD rose by more than 450 percent during the past half-century, from 10.8 gallons in 1946 to 49.2 gallons in 2000. At the same time, in the last 25 years, incidence rates of ACE have risen by more than 570 percent in American white males and continue to increase.

The rise in CSD consumption preceded the rise in cases of ACE by 20 years. A 40 percent increase for each five-year increase in date of birth – a birth cohort effect – was previously reported. Using linear regression to compare trends between CSD and ACE rates, the researchers found a highly significant correlation between the two (r=0.99, 95% CI 0.96-1.0).

Researchers found published data for a strong biological basis to explain the increased dose and duration of esophageal exposure to acid: CSD drinking causes gastric distension that triggers reflux. Consumption of 350 milliliters of CSD per day (approximately one can of soda) corresponds to 53.5 minutes of pH less than four and 53 gallons per year translates to 32,100 more minutes of acid exposure per year. Excess CSD consumption started in childhood and American teenagers drank two cans of CSD per day on average, which can explain the birth cohort effect.

White children drank significantly more CSD than black children. In general, identical time trends were seen worldwide, as countries with per capita CSD below 10 gallons (including Eastern Europe, Japan, China, Taiwan, Korea and India, among others) had little increase in the incidence of ACE.

Countries with per capita CSD of more than 20 gallons have seen a rising trend of ACE cases. “The surprisingly strong correlation demonstrates the impact of diet patterns on health trends,” said Mohandas Mallath, M.D., lead author on the study. “This study re-emphasizes a general life style dictum that ‘if little is good, a lot isn’t better.’ As the rates may continue to rise for another 20 years, we believe that more epidemiological studies are urgently required to establish the true association.”