Nutritional requirements for boron, silicon, vanadium, nickel, and arsenic: current knowledge and speculation.

Title	Nutritional requirements for boron, silicon, vanadium, nickel, and arsenic: current knowledge and speculation.
Authors	Forrest H. Nielsen
Magazine	The FASEB Journal
Date	09/01/1991
DOI	10.1096/fasebj.5.12.1916090
Introduction	The precise biochemical roles of ultratrace elements such as boron, silicon, vanadium, nickel, and arsenic in higher organisms remain undefined, despite their recognition as essential nutrients. Recent advancements in molecular biology, novel organism studies, and enzyme research have suggested potential critical functions for these elements. For instance, boron may influence cell membrane properties, whilst silicon might play a role in cell-macromolecule interactions, impacting cartilage formation. Vanadium could be crucial in halide ion oxidation and receptor protein phosphorylation, whereas nickel is necessary for CO2 fixation in metabolic processes. Arsenic possibly aids in the conversion of methionine to key metabolites. Should these theories prove accurate, the nutritional significance of these elements would be confirmed, although the required dietary amounts are likely minimal, measured in micrograms daily.
Quote	Forrest H. Nielsen. Nutritional requirements for boron, silicon, vanadium, nickel, and arsenic: current knowledge and speculation. FASEB J. 1991. Vol. 5(12):2661-2667. DOI: 10.1096/fasebj.5.12.1916090
Element	Boron (B) , Silicon (Si) , Vanadium (V) , Nickel (Ni) , Arsenic (As)