What is the use and function of CHROMIUM ?
Chromium (Cr) is an essential nutrient required for normal sugar and fat metabolism.
It potentiates the action of insulin. This mineral occurs throughout the body
with highest concentrations in the liver, kidney, spleen and bone.
Works with insulin in the metabolism of sugar and stabilizes blood sugar
levels; cleans the arteries by reducing Cholesterol & Triglyceride levels; helps
transport amino acids to where the body needs them; helps control the appetite;
medical research has shown that persons with low levels of Chromium in their
bodies are more susceptible to having cancer and heart problems and becoming
Signs of deficiency include impaired glucose tolerance and elevated circulating
insulin. In some studies, chromium supplementation has reduced total serum cholesterol,
triglycerides and apolipoprotein B and increased HDL-cholesterol. May result
in glucose intolerance in diabetics; atherosclerosis, heart disease, depressed
growth, obesity, tiredness.
Diet recommendations: The Estimated Safe and Adequate Daily Dietary
Intake (ESADDI) for adults is 50 to 200 µg. Usual dietary intakes in
the U.S. are about 25 µg/day for women and 33 µg/day for men.
Breast-fed infants consume less than 1 µg Cr/day and the ESADDI for infants
is 10 to 40 µg/day. The current ESADDI for chromium needs to be reevaluated,
especially for infants.
Food sources/bioavailability: Meat, poultry, fish and dairy products
are generally low in chromium. Fruits, vegetables whole grains and seeds are
better sources but have variable concentrations. Processing foods with stainless
steel equipment may increase their chromium concentration, especially if the
foods are acidic. In addition, there are differences in bioavailability and
biological activity of the different complexes found in foods.
Toxicity: Both solubility and oxidation state affect the potential
for toxicity; furthermore, the type of complex may impact toxicity. Toxic effects
are limited primarily to industrial exposure to hexavalent chromium, which is
much more toxic than the trivalent form. The hexavalent chromium compounds may
be carcinogenic. The acidity of the stomach promotes reduction of hexavalent
chromium to the trivalent form. Most of the chromium absorbed from the gastrointestinal
tract is trivalent. The Reference Dose (RfD) for trivalent chromium is 1
µg/kg/day. This level is more than 300-fold the upper limit of the ESADDI,
making trivalent chromium one of the least toxic minerals.
Recent research: In humans undergoing resistive training, chromium
does not consistently promote a significant increase in strength and lean body
mass. In pigs chromium improves lean body mass and litter size. Immune function
in stressed farm animals is improved by chromium. Sugar-induced increases in
blood pressure of spontaneously hypertensive rats are prevented by chromium.
Chromium may compete with iron for binding to transferrin.
For further information:
Mertz, W. (1993) Chromium in human nutrition: a review. J. Nutr. 123: 626-633
Anderson, R.A. (1995) Chromium, glucose tolerance, diabetes and lipid metabolism.
J. Advancement Med. 8: 37-48
Stoecker, B.J. (1996) Chromium. In: Present Knowledge in Nutrition (Ziegler,
E.E. & Filer, L.J., Jr., eds.), 7th ed. ILSI Press, Washington, DC.