Bone Abstracts

Increasing attention has focused on micronutrients such as vitamin K, magnesium, boron and isoflavones supplements for osteoporosis. This talk will look at the evidence, misconceptions and their clinical relevance. Vitamin K, phylloquinone (K1) and menaquinone (K2), may improve bone health through activation of osteocalcin involved in bone mineralisation. Observational studies have shown that low vitamin K intake or serum levels are associated with low bone mineral density (BMD) and increased fracture risk. However, these findings have not been substantiated in clinical trials investigating the effects of supplemental vitamin K1 or K2, mainly menaquinone-4 (MK4). Results are inconsistent across populations and benefits are marginal even in those with low vitamin K status. Current evidence does not support the broad use of vitamin K supplements beyond the recommended dietary intake, unless in patients with malabsorptive disorders. Magnesium plays a role in the synthesis of bone matrix and mineralisation. Some observational studies have shown a positive relationship between higher magnesium intake and hip and femoral neck BMD. Interventional trials are small and heterogeneous and difficult to interprete. Large randomised controlled trials, particularly in older people, are needed to establish its role in bone health. Nonetheless, ensuring adequate dietary magnesium intake is widely recommended, with supplementation reserved for individuals with documented deficiency. Boron is involved in mineral and steroid hormone metabolism. There is a lack of strong evidence supporting the effectiveness of boron supplements on bone health. The optimal daily dosage for bone health is unclear and there are potential risks of excessive boron intake. Isoflavones, primarily derived from soy, exhibit weak estrogenic activity. Meta-analyses indicate small improvements in BMD, particularly in the lumbar spine in post-menopausal women. However, the results remain inconclusive due to variability in study designs, treatment duration, the type and dose of isoflavone. Current clinical guidelines do not endorse routine use of these supplements for osteoporosis due to insufficient high-quality evidence. Their availability in natural food sources may provide sufficient amounts without supplementation. Their use may be considered in individuals at risk of deficiencies due to reduced absorption. Further studies are required to clarify their efficacy and safety profiles.