Hip fracture risk is not associated with adherence to plant-based diets among postmenopausal women, according to a recent study published in JAMA Network Open.
Takeaways
- Contrary to concerns, adherence to plant-based diets among postmenopausal women does not appear to increase the risk of hip fractures, as revealed by a recent study.
- While nutrient intake, including vitamin D, vitamin K, and calcium, plays a crucial role in bone health, the study found no significant association between plant-based diet quality and hip fracture risk.
- The study involved a large cohort of postmenopausal women from the Nurses’ Health Study, providing robust data on diet, lifestyle, and health factors over time to assess the relationship between diet and hip fracture risk.
- Researchers developed two Plant-Based Diet Indexes to evaluate diet quality, distinguishing between healthful and unhealthful plant-based foods. However, neither index showed a clear link to hip fracture risk over the long term.
- These findings suggest that long-term adherence to plant-based diets does not increase the risk of hip fractures among postmenopausal women. Further studies are needed to explore the potential impact of dietary patterns and reverse causality on bone health outcomes.
Bone mass decreases with age, leading to increased bone fracture risk among older individuals. The risk is especially prominent among postmenopausal women, with a fragility fracture reported in 1/3 women aged over 50 years.
Bone mineralization is impacted by nutrient intake, with nutrients such as vitamin D, vitamin K, and calcium associated with decreased bone loss. Concerns have arisen that plant-based diets, in which individuals consume more plant foods and have a decreased intake of animal foods, may adversely impact bone health.
Investigators conducted a study to evaluate the impact of plant-based diet quality and hip fracture risk among postmenopausal women. Participants included women in the Nurses’ Health Study (NHS), a prospective cohort study including US female registered nurses aged 30 to 55 years.
Medical history and health-related information was collected from NHS participants every 2 years, while diet information was collected every 4 years using the food frequency questionnaire (FFQ). The FFQ asked women about previous 12-month diet intake. White women were included in the analysis upon reaching menopause.
Exclusion criteria included different races and ethnicity, cancer, prior hip fracture or osteoporosis, and missing diet information. Two Plant-Based Diet Indexes (PDIs) were developed: a healthful PDI (hPDI) and unhealthful PDI (uPDI).
Eighteen food groups were developed, comprising 3 larger categories: healthy plant foods, less healthy plant foods, and animal foods. Healthy plant foods received a positive score and other foods received a negative score in the hPDI, while less healthy plant foods received a positive score and other foods received a negative score in the uPDI.
Hip fractures were reported through biennial questionnaires. Data related to the fracture included month and year of occurrence, circumstances surrounding the fracture, and level of trauma. High-impact fracture traumas were excluded from the analysis.
Additional data obtained included body mass index (BMI), age, thiazide use, smoking status, anti-inflammatory steroid use, postmenopausal hormone treatment, and furosemide-like diuretic use. Multivitamin use was reported, as well as supplementation with vitamin D, retinol, and calcium.
There were 70,285 participants in the study, among whom 2038 hip fracture cases were reported to the NHS. Participants were aged a mean 54.92 years at baseline, and mean hPDI and uPDI scores were 54.33 and 54.38, respectively. A mean BMI of 25.69 and mean consumption of 1743.65 kcal were reported.
Patients with improved hPDI scores were more physically active, leaner, more often used vitamin and calcium supplements, smoked less, and had higher healthy plant foods and calcium intake and lower less healthy plant foods intake. Lower energy and vitamin D supplementation intake was reported among patients with greater adherence to the hPDI and uPDI.
An association was not reported between long-term hPDI or uPDI scores and hip fracture risk, with a hazard ratio of 0.97 when comparing the highest and lowest income quartiles for the hPDI and 1.02 for the uPDI. However, a 21% reduced risk of hip fracture was reported for the hPDI when examining recent intake.
These results indicated there is not an association between long-term plant-based diet and hip fracture risk. Investigators recommended future research determine whether dietary patterns, reverse casualty, or both are associated with recent dietary intake results.
Reference
Sotos-Prieto M, Rodriguez-Artalejo F, Fung TT, et al. Plant-based diets and risk of hip fracture in postmenopausal women. JAMA Netw Open. 2024;7(2):e241107. doi:10.1001/jamanetworkopen.2024.1107
