The obesity paradox and osteoporosis risk: A gender-specific finding in older adults
A new study published in BMC Geriatrics has shed light on the "obesity paradox" in osteoporosis risk, revealing significant gender differences among older adults.
The study explores how obesity affects the risk of osteoporosis, particularly in women, using data from over 177,000 participants in the UK Biobank.
The obesity paradox suggests that, contrary to common belief, higher levels of body fat may be associated with a reduced risk of certain diseases, including osteoporosis. However, the evidence surrounding this relationship has been inconsistent. This study aimed to clarify the connection between obesity and osteoporosis risk in an older population.
The researchers analysed body mass index (BMI), waist circumference (WC), and body fat percentage (BFP) and their association with bone mineral density (BMD), a key indicator of osteoporosis. The results highlighted in women, higher BMI, WC, and BFP were strongly linked to better BMD, whereas the same associations were weak or absent in men.
Over a median follow-up period of 13.7 years, 8,998 participants were diagnosed with osteoporosis. Cox regression analysis revealed that in women, higher obesity metrics, such as BMI, WC, and BFP, were associated with a 23 per cent to 33 per cent reduced risk of osteoporosis. However, no such association was observed in men.
The study also demonstrated an inverse J-shaped relationship between obesity and osteoporosis risk in women, with the lowest osteoporosis risk observed in women with higher BMI and body fat.
The study’s findings highlight a significant gender discrepancy, while lower BMI is an independent risk factor for osteoporosis in older adults, the obesity paradox exists only in women. In other words, higher BMI and body fat may offer protective benefits against osteoporosis for women, but not for men.
These results emphasise the need to tailor osteoporosis risk management strategies based on gender, considering the differing impacts of body weight and composition on bone health.