A study of twelve post-menopausal women aged between 48 and 72 found that supplementing a low-boron, low-magnesium diet with three grams of boron a day for 48 days both (i) increased 17 beta-estradiol* and testosterone levels and (ii) reduced calcium and magnesium levels in the urine.

This suggested that the boron supplement had reduced both calcium loss and bone demineralisation, thus reducing bone erosion and protecting against osteoporosis

* the most powerful form of natural oestrogen

View boron-based Osteo-trace supplement

Ed. However, another similar study found no evidence that boron supplementation had reduced urine calcium loss.[1]