Tea Linked to Stronger Bones in Older Women, Heavy Coffee Use to Weaker Ones, Study Finds

Researchers at Flinders University have found that coffee and tea appear to have different relationships with bone health in older women. Published in the journal Nutrients, the study tracked nearly 10,000 women aged 65 and older for 10 years, examining links between coffee and tea consumption and bone mineral density (BMD), a measurement used to gauge osteoporosis risk — weakened, fracture-prone bones. Osteoporosis affects roughly one in three women over 50 and causes millions of fractures each year.

The team used data from the Study of Osteoporotic Fractures, repeatedly recording coffee and tea habits and measuring BMD at the hip and femoral neck, two sites closely linked to fracture risk.

Women who drank tea had slightly higher total hip BMD than non-tea drinkers — a small but statistically significant difference. "Even small improvements in bone density can translate into fewer fractures across large groups," said Adjunct Associate Professor Enwu Liu of Flinders University. Co-author Ryan Liu said catechins, compounds abundant in tea, may promote bone formation and slow bone breakdown.

Coffee's picture was more mixed. A moderate amount — about two to three cups a day — was not associated with harm to bone health, but women who drank more than five cups a day had lower BMD. The negative link was stronger among women with higher lifetime alcohol consumption, while tea's benefit was more pronounced in women with obesity. Ryan Liu said laboratory studies show caffeine can interfere with calcium absorption and bone metabolism, though the effect is small and can be offset by adding milk.

The researchers noted the differences observed were modest — statistically significant, but not large enough to justify major changes to daily habits. The paper was published in Nutrients by Ryan Yan Liu and Enwu Liu.