Background/Aims: Observational studies have linked tea drinking, a major source of dietary flavonoids, with higher bone density. The objective of this study was to examine the associations of black tea drinking and flavonoid intake with fracture risk in a prospective cohort of women aged over 75 years.
Methods: A total of 1,188 women were assessed for habitual dietary intake with a food frequency and beverage questionnaire. Incidence of osteoporotic fracture requiring hospitalization was determined through the Western Australian Hospital Morbidity Data system. Multivariable adjusted Cox regression was used to examine the hazard ratios (HR) for incident fracture.
Results: Over 10 years of follow up, osteoporotic fractures were identified in 288 (24.2%) women, of which 129 (10.9%) were a hip fracture. Compared to the lowest tea intake category (≤1 cup/week), consumption of ≥3 cups/day was associated with a 30% decrease in the risk of any osteoporotic fracture (HR: 0.70; 95%CI: 0.50, 0.96). Compared to women in the lowest tertile of total flavonoid intake women in the highest tertile had a lower risk of any osteoporotic fracture (HR: 0.65; 95%CI: 0.47, 0.88) or hip fracture (HR: 0.58; 95%CI: 0.36, 0.95). For specific classes of flavonoids, reductions in fracture risk were observed for higher intake of flavonols with any osteoporotic fracture, and flavones with hip fracture (P<0.05).
Conclusions: Higher intake of black tea and particular classes of flavonoids were associated with lower risk of fracture-related hospitalizations in elderly women at high risk of fracture.
Funding source(s): Healthway; NHMRC