An overview on the correlation between blood zinc, zinc intake, zinc supplementation and bone mineral density in humans.

Introduction In case of zinc (Zn) deficiency, this mineral becomes a nutrient limiting muscle and bone synthesis. The study in humans on zinc and bone health are few and no reviews have been published on this topic. So, the aim of this narrative review was to consider the state of the art on the correlation between blood zinc, daily zinc intake, zinc supplementation and bone mineral density. Material and methods A narrative review was performed. Results This review included 16 eligible studies: eight studies concern Zn blood; three studies concern Zn intake and five studies concern Zn supplementation. Conclusion Blood zinc levels seem to be lower in subjects with pathology related to bone metabolism. Regarding daily zinc intake, a high proportion of the population, more than 20%, seems to be at risk of having inadequate zinc intake. The literature suggests that an insufficient zinc intake (less than 3 mg/day) could be a risk factor for fractures and for development of osteopenia and osteoporosis. Zinc supplementation (40-50 g/day) could have beneficial effects on bone health in terms of maintaining bone mineral density and faster healing in the event of fractures, with even better results in situations of reduced intake zinc through food.