Also,

see this paper, it was the first result in a search on boron supplementation and osteoporosis:

https://pubmed.ncbi.nlm.nih.gov/32540741/

Pivotal role of boron supplementation on bone health: A narrative review Mariangela Rondanelli 1, Milena Anna Faliva 2, Gabriella Peroni 3, Vittoria Infantino 4, Clara Gasparri 5, Giancarlo Iannello 6, Simone Perna 7, Antonella Riva 8, Giovanna Petrangolini 9, Alice Tartara 10 Affiliations Expand PMID: 32540741 DOI: 10.1016/j.jtemb.2020.126577 Free article Abstract Background: Boron is a trace element that plays an important role in numerous biological functions, including calcium metabolism, growth and maintenance of bone tissue. However, there are still no precise indications regarding a possible role of boron supplementation, and its amount of supplementation, to maintain bone health. So the aim of this narrative review was to consider the state of the art on the effectiveness of boron supplementation (alone or with other micronutrients) on growth and maintenance of bone in humans through control of calcium, vitamin D and sex steroid hormone metabolism in order to suggest a daily dosage of boron supplementation.