Boron is a mineral. Because a biochemical function has not been established for boron, no nutritional guidelines have been set. However boron has beneficial, if not essential effects, according to the USDA.

Boron plays a role in cell-membrane functions that influence hormones as well as the transport of calcium. Studies show that boron has a beneficial role in energy and metabolism, it enhances the response to estrogen therapy, improves motor skills and cognitive processes including attention and memory.

References

Nielsen FH The justification for providing dietary guidance for the nutritional intake of boron Biol Trace Elem Res 1998 Winter;66(1-3):319-30, Sutherland B, Strong P, King JC Determining human dietary requirements for boron. Biol Trace Elem Res 1998 Winter;66(1-3):193-204. Hunt CD. Biochemical effects of physiological amounts of dietary boron. J Trace Elem Exp Med. 1999; 9:185-213.