new study shows elderly women who drank tea had higher bone density in
their hips and less bone loss than women who didn't drink tea.
Researchers say the results confirm previous studies that have suggested
drinking tea may protect against bone loss and osteoporosis.
In the study, Australian researchers surveyed 275 women between the ages
of 70 and 85 who were participating in a larger five-year study of calcium
supplements and osteoporosis about how much black and green tea (but not
herbal teas) they drank. Bone density measurements of the hip were also
taken at the beginning and end of the five-year study.
The results, published in The American Journal of Clinical Nutrition,
showed that women who were regular tea drinkers had higher bone density
in two sites in the hip compared with non-tea drinkers.
The bone mineral density in tea drinkers was higher than in non-tea drinkers.
Tea drinkers also had less loss of bone density over a four-year period
compared with non-tea drinkers. These results took into account factors
such as smoking history and use of calcium supplements.
The researchers did not find a relationship between the number of cups
of tea consumed per day and bone mineral density.
"Other variables, such as dietary calcium and coffee intake, physical
activity, and smoking did not appear to be important confounders of the
relation between tea and [bone density]," write researcher Amanda
Devine, of the University of Western Australia in Perth, Australia, and
colleagues. "Thus, overall our data support the concept that tea
intake has beneficial effects on bone structure by reducing bone loss."
Researchers say more research is needed to determine how drinking tea
affects bone density. Previous studies have suggested that phytochemicals
in - tea, such as flavonoids, may be responsible for the protective effect
against bone loss due to their estrogen-like properties.
By Jennifer Warner
Reviewed by Louise Chang
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