Results of a study conducted in China indicate that
drinking tea reduces the risk of bile stones and cancer,
especially among women.
Bile stones, which are often seen in women and have
been linked to obesity, occur in the ducts that transfer
bile from the liver to the small intestine. If the
stones block the opening of the gallbladder, they
can cause discomfort and pain, typically located just
below the rib cage on the right side of the abdomen.
At this stage, gallbladder removal, or "cholecystectomy,"
is often required. Serious complications from bile
stones are uncommon.
By contrast, "biliary tract cancers...are rare but
highly fatal," Dr. Ann W. Hsing, of the
National Cancer Institute, Bethesda, Maryland,
and colleagues write in the International Journal
of Cancer.
"Apart from gallstones, (causative) factors for biliary
tract cancer are not clearly defined," they note.
Several studies "have suggested that consumption of
tea, especially green tea, is protective against a
variety of cancers."
In the new study, the researchers examined the effects
of tea consumption on the risk of biliary tract cancers
and biliary stones. Included in the study were 627
patients with biliary tract cancer, 1,037 with biliary
stones, and 959 comparison subjects.
The team obtained data on demographics, medical and
dietary factors, and tea consumption. Tea drinkers
were defined as those who drank at least one cup of
tea per day for at least 6 months. Of the 959 control
subjects, 394 (41 percent) were ever tea drinkers.
In women, drinking at least one cup of tea per day
for at least 6 months seemed to cut the risks of bile
stones by 27 percent, gallbladder cancer by 44 percent,
and bile duct cancer by 35 percent. In men, tea drinking
had a similar effect, but not of the magnitude seen
in women.
Certain chemicals in tea may prevent cells from growing
abnormally and may have antiinflammatory effects that
reduce the risk of these bile tract diseases, Hsing's
team explains. Further studies are needed to see if
these findings can be duplicated.
SOURCE: International Journal of Cancer, June 2006.
