Summary:
Bone strength is influenced by bone size and bone mineral density, with peak bone mass reached in early adulthood. The amount of bone gained during childhood plays an important role in lifelong health, meaning that poor bone development early in life may increase the risk of osteoporosis and fractures in later years. While genetics contribute to bone development, environmental and lifestyle factors including physical activity and nutrition also influence bone mass. Research has shown that access to green space during childhood is associated with a range of health benefits, including improved mental wellbeing, healthier body weight, lower blood pressure and increased physical activity. However, little research has examined whether living near green spaces also supports bone health. This study was a prospective cohort study that investigated whether exposure to green space during early childhood was associated with increased bone mineral density in children. The study followed 327 mother-child pairs from birth until the children were 4-6 years old. Researchers measured the amount of green space surrounding each child’s home and then assessed bone mineral density. This study found that greater exposure to residential green space was associated with better bone health in young children. Children living in areas with more total vegetation had higher bone mineral density and were less likely to have bone density in the lowest 10% for their sex. The strongest associations were observed for green space located within 500-1000 metres of the home. Overall, this study suggests that living near green space during early childhood may support healthy bone development during a critical stage of growth. The findings indicate that access to residential green space could contribute to improved bone health and potentially reduce the risk of osteoporosis and fractures later in life.
Read the Complete Article >
Abstract:
Importance: Bone mass accrual is influenced by environmental and lifestyle factors. Targeted interventions at the early stages of life might decrease fracture and/or osteoporosis risk later in life. Objective: To investigate whether early-life exposure to residential surrounding green space is associated with a change in bone mineral density in young children. Design, Setting, and Participants: In this prospective birth cohort study (ENVIRONAGE [Environmental Influence on Aging in Early Life]), mother-child pairs from Flanders, Belgium, were recruited at birth and followed up for 4 to 6 years, between October 1, 2014, and July 31, 2021. Data analysis was conducted between January and February 2022. Exposures: Green space was estimated for high green (>3 m vegetation height), low green (≤3 m vegetation height ), and total green (sum of high and low) within several radii (100-3000 m) around the residence after geocoding of the addresses. Main Outcomes and Measures: Radial bone mineral density was assessed using quantitative ultrasound measurement at follow-up, measured as the mean of the axially transmitted speed of sound in meters per second. Multiple linear and logistic regression models were used while accounting for relevant covariates and potential confounders. Results: The study population comprised 327 children (180 [55.0%] female; mean [SD] age, 4.6 [0.4] years at the follow-up evaluation). Early-life exposure to residential green space was associated with increased childhood bone health. An IQR increment in total green (21.2%) and high green (19.9%) space within 500 m was associated with an increase of 27.38 m/s (95% CI, 9.63-45.13 m/s) and 25.30 m/s (95% CI, 7.93-42.68 m/s) in bone mineral density, respectively. Additionally, an IQR increase in total (25.2%) and high (23.2%) green space within 1000 m was associated with a 67% (odds ratio, 0.33; 95% CI, 0.17-0.61) and 61% (odds ratio, 0.39; 95% CI, 0.18-0.75) lower risk of having a bone density lower than the sex-specific 10th percentile (3567.6 m/s for girls and 3522.8 m/s for boys). Conclusions and Relevance: In this study of children aged 4 to 6 years, higher bone mineral density and a lower risk of having low bone density were associated with higher residential green space exposure during childhood. These findings highlight the importance of early-life exposure to residential green space on bone health during critical periods of growth and development, with long-term implications.
Article Publication Date: 04/01/2024
DOI: 10.1001/jamanetworkopen.2023.50214
