The safety and efficacy of high-dose chromium - High-Dose Chromium

Alternative Medicine Review, June, 2002 by Davis W. Lamson, Steven M. Plaza

Absorption of chromium is low, as it is for other polyvalent minerals, ranging from less than one percent for Cr III chloride to above one percent for Cr III nicotinate to 1-3 percent for Cr III picolinate in rat studies. Human absorption from food is estimated at about 2-3 percent and 510 percent from brewer's yeast. Absorption of inorganic Cr is increased by starch or ascorbic acid. Concurrent supplementation with zinc, iron, manganese, or calcium retards Cr absorption. Concurrent mixed amino acids increased Cr absorption. High-dose Cr in rats increased iron content in liver and spleen, while decreasing the level in heart.

In humans, dietary Cr III absorption is inversely related to dietary intake, varying from 0.5-2 percent. Several drugs increase Cr absorption, while several antacids decrease it, supposedly due to competitive inhibition by the minerals in the antacids. In animal studies, the retention of Cr from supplementation occurred chiefly in the kidneys, followed by liver and heart muscle. The order of retention was Cr III picolinate > Cr III nicotinate > Cr III chloride, which varies from the order of absorption. No disturbances in the organ systems showing high concentration of Cr have yet been detected

The overall chromium picture causes the authors to question whether there is enough chromium in the national diet or if we are absorbing it appropriately. The authors believe higher doses of Cr than are generally prescribed by nutritionally oriented physicians may be appropriate for type 1 and 2 diabetes. At this time, there is no demonstration of general chromium toxicity in animals at a dose that would extrapolate to humans as 1050 mg daily, recalling that the RfD for humans is 70 mg daily.

One of the authors has employed high dose chromium as nicotinate for the treatment of type 2 diabetes patients at the level of 3000-4000 mcg twice daily (based on previously unpublished research by Jonathan Wright, MD), with outstanding reductions of glucose and lipid levels in many. None of the patients, followed for months to years, have shown increases in BUN or liver enzymes or other laboratory abnormalities. Further studies on safety and efficacy of this high-dose range are being conducted.

Table 1. Absorption and Retention of Various Chromium Compounds

Type of Chromium        % Blood Absorption

Chloride                0.9 [  or -] 0.2 (4 hrs.) (81)
                        0.69 (mean range 0.3-1.3) (82)
                        0.5 (83)

Nicotinate              1.3 [  or -] 0.3 (81)

Picolinate              1.1 [  or -] 0.3 (81)
                        2.8 [  or -] 1.14 SD (84)

Dinicotinic acid        0.6 [  or -] 0.1 (81)
diglycine cysteine
glutamic acid complex

Chromium from food.     1.8 (36.8 mcg Cr/day) (79)
                        2-3 (85)

Chromium from brewers   5-10 (82)
yeast

Type of Chromium        Test Subject

Chloride                Rat
                        Human
                        Rat

Nicotinate              Rat

Picolinate              Rat
                        Human

Dinicotinic acid        Rat
diglycine cysteine
glutamic acid complex

Chromium from food.     Human
                        Human

Chromium from brewers   Human
yeast
Table 2. Chromium Concentration in Rat Organs
Following Supplementation

Form of Cr
(ng/g, dry wt.)   Kidney   Liver   Heart   Gastrocnemius

Picolinate        374      49      28      25

Nicotinate        170      14      12      11

Chloride          78       10      4.6     14

Control           20       4.7     12      16

Chromium concentrations in rat organs after chromium supplemented
diet (5000 ng Cr/g diet) for three weeks vs. low-chromium diet.
Adapted from Anderson et all (81) by analysis of published graphs.