Even though it is listed in the periodic table,1 the metallic element boron is not a naturally occurring element. It is found in small amounts in the earth’s surface, and it is thought to be produced solely by the collection of particulate matter of meteorites; in this form, it is water-soluble. The largest known deposit of this mineral is in Turkey, which produces more than 47% of the world’s supply.2
Borax (the common name for the mineral salt of boron) was used in China as long ago as 300 AD and Persian alchemists used it in their process of glazing pottery. Other records discuss its use as a flux in metal work. Then, in 1777, the soluble boric acid was found in hot springs near Florence, Italy. This is the first mention of boron’s medicinal use.
Boron was not classified as an element until 1809. Many Americans are familiar with the product ‘Twenty-Mule Team Borax,’ a brand name of a soap called ‘Boraxo.’ Borax was first found in the United States in the arid desert Southwest in the late 1800s. It became popular as a soap during this mining era when it was found to emulsify heavy dirt and oil on wet hands.
In humans, the role of boron was discovered only recently, and the information continues to accumulate. One of the best-studied functions of boron is in the metabolism of human bone. Laboratory research discovered boron to be an essential trace element in the survival, proliferation, and mineralization of osteoblasts and required for messenger RNA production of the proteins associated with this process.2 Further studies have demonstrated the osteogenic effects of boron on bone marrow stromal cells.3 Researchers found that treatment of laboratory cell cultures with supplemental boron led to increased calcium depositions when compared to untreated cells.3 These findings suggest a significant step in the prevention of osteoporosis and its related sequelae.
Boron also appears to play a significant role in wound healing. Wound healing involves the epithelial cell type known as keratinocyte. The actual process requires both migration and proliferation of new cells.4 One in-vitro study of human keratinocyte cultures studied the effect of varied strengths of boron solution on culture media on which an intentional 2-mm gap had been formed. After 24 hours, the cell culture treated with boron showed ‘gap closure’ to be 20% greater than the control culture.4 Boron has also been found to be essential for the production of vascular endothelial growth factor (VEGF).5
There is also a high level of interest in boron’s potential role in cancer prevention and treatment. To date, the best studied cancers are prostate and cervical. One study followed more than 1,000 women to monitor for abnormal cervical cytology.6 The women were categorized as having a high- or low-intake of dietary boron; there was an approximate difference of nearly 7 mg/d of dietary intake between the two groups. Women in the high-intake group had no abnormal cytological findings, whereas 15 women in the low intake group were found to have abnormal findings.