Chromium as an essential nutrient: a review

Abstract

Chromium (Cr) has been studied since the end of the 19 th century, when carcinogenic effects of hexavalent Cr were discovered. Essentiality of trivalent Cr was demonstrated in 1959; Cr 3+ has been studied in humans and laboratory animals since the 1970s and it is only since the 1990s that Cr has been studied as an essential element in livestock animals with the same intensity. Trivalent chromium is essential to normal carbohydrate, lipid and protein metabolism. Chromium is biologically active as part of an oligopeptide -chromodulin -potentiating the effect of insulin by facilitating insulin binding to receptors at the cell surface. With chromium acting as a cofactor of insulin, Cr activity in the organism is parallel to insulin functions. Cr absorption is low, ranging between 0.4 and 2.0% for inorganic compounds while the availability of organic Cr is more than 10 times higher. Absorbed Cr circulates in blood bound to the β-globulin plasma fraction and is transported to tissues bound to transferrin. Absorbed Cr is excreted primarily in urine, by glomerular filtration; a small amount is excreted through perspiration, bile and in milk. The demand for Cr has been growing as a result of factors commonly referred to as stressors, especially during different forms of nutritional, metabolic and physical strain. This review describes Cr metabolism, the different biological functions of Cr and symptoms of Cr deficiency.

Chromium chloride increases insulin‐stimulated glucose uptake in the perfused rat hindlimb

“…It has been shown that chromium does not act alone but only in the presence of insulin (22,51). This has been confirmed in the present study.…”

“…Many studies have shown that chromium supplementation increases glucose metabolism in insulin resistant populations (16,38,51). However, when healthy subjects have been examined, it has been shown that chromium has no effect on glucose metabolism (14,70).…”

“…However, when chromium is supplemented orally, there is little difference in the valence activity of the element. Some researchers suggest that chromium (VI) is reduced to chromium (III) when ingested orally (26,51). In humans Earlier animal work has shown that when chromium (VI) is given intravenously or intratracheally, the plasma concentration levels drop at an accelerated rate compared to the red blood cell chromium concentrations (28,32,69).…”

Trivalent chromium (CrIII) as a trace element essential for animals and humans

“…XX w. potwierdziły niezbędność chromu dla różnych gatunków zwierząt (bydło, owce, konie, świnie i drób) (82). Chrom wpływa na metabolizm glukozy i tłuszczów u kotów, małp, świnek morskich, królików, wiewiórek, drobiu, indyków, świń, cieląt oraz człowieka (85).…”

“…Chrom trójwartościowy był używany jako wskaźnik badań strawności paszy i barwy (41,82). Absorpcja Cr(III) zależy od jego zawartości w diecie, chemicznej formy i innych składników żywieniowych (19,20).…”