Scientific study suggests drinking tea strengthens bones

By Stephen Beech

Drinking tea strengthens the bones of older women, a new study suggests.

A daily cuppa could be a simple way to boost bone health as we age, say scientists.

But they warned that coffee has the opposite effect - with drinking more than five cups a day raising the risk of fractures.

The study, by researchers at Flinders University in Adelaide, South Australia, offers new insight into how two of the world’s most popular hot drinks may influence bone health in older women.

The research team followed nearly 10,000 women aged 65 and older over a decade to explore whether their daily habits of drinking coffee or tea were linked to changes in bone mineral density (BMD), a key indicator of osteoporosis risk.

Osteoporosis is a major global health concern, affecting one in three women over 50 and contributing to millions of broken bones each year.

Evidence of the relative benefits or not of drinking tea or coffee has been mixed until now, with few studies having tracked the relationships over such an extended period.

The Flinders University team analyzed data from the Study of Osteoporotic Fractures, using repeated measures of both tea and coffee intake and BMD at the hip and femoral neck, areas strongly associated with fracture risk.

Over 10 years, participants reported their coffee and tea consumption, while researchers measured bone density using advanced imaging techniques.

The findings, published in the journal Nutrients, showed that tea drinkers had a slightly higher total hip BMD compared to non-tea drinkers.

While the difference was modest, the research team said it was "statistically significant" and could have meaningful implications at a population level.

Study co-author Dr. Enwu Liu, of Flinders University's College of Medicine and Public Health, said: “Even small improvements in bone density can translate into fewer fractures across large groups."

But he said coffee told a more "complex story."

Dr. Liu said: "Overall, moderate coffee consumption, about two to three cups per day, did not appear to harm bone health.

"However, drinking more than five cups daily was linked to lower BMD, suggesting that excessive intake may be detrimental.

"Interestingly, women with higher lifetime alcohol consumption experienced more negative effects from coffee, while tea seemed particularly beneficial for women with obesity."

Study co-author Ryan Liu says that compounds called catechins, abundant in tea, may promote bone formation and slow bone breakdown.

Flinders researcher Liu said: “Coffee’s caffeine content, by contrast, has been shown in laboratory studies to interfere with calcium absorption and bone metabolism, though these effects are small and can be offset by adding milk."

Dr. Liu says that the findings suggest that enjoying a cup of tea every day could be a simple way to support bone health as we age.

He added: “While moderate coffee drinking appears safe, very high consumption may not be ideal, especially for women who drink alcohol."

The research team cautioned that the observed differences, while statistically significant, are not large enough to warrant people making dramatic changes.

Dr. Liu said: “Our results don’t mean you need to give up coffee or start drinking tea by the gallon.

“But they do suggest that moderate tea consumption could be one simple way to support bone health, and that very high coffee intake might not be ideal, especially for women who drink alcohol.

“While calcium and vitamin D remain cornerstones of bone health, what’s in your cup could play a role too."

He added: "For older women, enjoying a daily cup of tea may be more than a comforting ritual, it could be a small step toward stronger bones."