Chromium (Cr) - General Discussion

Chromium activates phosphoglucosonetase and other enzymes and is tightly associated with GTF (glucose tolerance factor - a combination of Chromium III, dinicotinic acid and glutithione). The reported plasma levels of chromium in humans over the past 20 years has ranged from 0.075 to 13 ng/ml. Concentrations of chromium in human hair is ten times greater than in blood making hair analysis a much more accurate view of chromium stores and function in the human (there is 1.5mg in the human body).

Very little inorganic chromium is stored in the body, once inorganic chromium is absorbed, it is almost entirely excreted in the urine (therefore urine chromium levels can be used to estimate dietary chromium status). Dietary sugar loads (i.e.- colas, apple juice, grape juice, honey, candy, sugar, fructose, etc.) increase the natural rate of urinary Chromium loss by 300 % for 12 hours.

Diseases and Symptoms of Chromium Deficiency.

- Low blood sugar
- Pre-diabetes
- Diabetes (ulcers/gangrene) (Fig.
- Hyperinsulinemia
- Hyperactivity
- Learning disabilities
- ADD/ADHD
- Hyperirritability
- Depression
- Manic depression
- "Bi-polar" disease
- Dr. Jykell/Mr. Hyde rages ("Bad Seeds")
- Impaired growth
- Peripheral neuropathy
- Negative nitrogen balance (protein loss)
- Elevated blood triglycerides
- Elevated blood cholesterol
- Coronary blood vessel disease
- Aortic cholesterol plaque
- Infertility and decreased sperm count
- Shortened life span

The average intake of 50 to 100 ug of inorganic chromium from food and water supplies only 0.25 to 0.5 ug of usable chromium, by contrast 25 % of chelated chromium is absorbed. The chromium RDA for humans is a range of 50 to 200 ug per day for adults.

The concentration of chromium is higher in newborn animals and humans than it is in later life. In fact, the chromium levels of unsupplemented human tissue steadily decreases throughout life -- of even more concern has been the steady decline in the average American serum chromium since 1948: from 28-1000 mcg/l in 1948 to 0.73-1.6 mcg/l in 1973 to 0.13 mcg/l in 1985.

The fasting chromium plasma level of pregnant women is lower than that of nonpregnant women. Increasing impairment of glucose tolerance in "normal" pregnancy is well documented and reflects a chromium deficiency oftentimes resulting in pregnancy onset diabetes. One study demonstrated abnormal glucose tolerance in 77 percent of clinically "normal" adults over the age of 70. According to Richard Anderson, USDA, "90 percent of Americans are deficient in chromium."
Gary Evans, Bemidji State University, Minnesota, very clearly showed an increased life span in laboratory animals by 33.3 per cent when they were supplemented with chromium. Prior to this study gerontologists felt a severe restriction of calories was the only way to extend life past the expected average.

Deficiencies of chromium in humans are characterized by a wide variety of clinical diseases as well as a shortened life expectancy. The clinical diseases of chromium deficiency are aggravated by vanadium deficiency.

Chromium is a trace mineral nutrient, needed only in minute amounts to help increase the body's sensitivity to the hormone insulin for efficient utilization of surplus GLUCOSE. Chromium represents one of the most recently identified nutrients, and its role in metabolism was discovered in 1969. Chromium is converted in yeast and in tissues to GLUCOSE TOLERANCE FACTOR, in which chromium is complexed with nutrients like amino acids and niacin. In this form chromium can assist insulin. As a supplement, chromium may be effective in alleviating elevated blood sugar (hyperglycemia) in some elderly patients, and in some diabetics, as well as in healthy, non-diabetic people. It may protect against a form of non-insulin-dependent diabetes. However, clinical studies of this aspect have yielded mixed results. Chromium may protect against cardiovascular disease by helping to regulate fat and cholesterol synthesis in the liver and by raising HDL ("desirable" cholesterol) and by lowering LDL ('"undesirable") in the blood. Chromium also seems to help reduce high blood pressure (hypertension) in some cases.

Only the less oxidized form of chromium (Cr³⁺) is biologically active and can be used by cells. The more oxidized form (Cr⁺⁶) is a toxic industrial waste product, which is not formed in the body. The human body contains only very low levels of chromium (an estimated 6 mg or less). Chromium in food is poorly assimilated and only 1% to 5% of dietary chromium is absorbed. It is estimated that 90% of Americans consume less than 40 mcg of chromium daily, and many people may be chromium deficient, especially elderly persons, pregnant or lactating women, athletes, and healthy people who rely on processed food. Chromium loss increases with injury, stress, aging and strenuous exercise. Consuming excessive sugar increases chromium losses from the body and lost chromium is slow to be replaced. Consequently chromium levels decline with age.

Chromium deficient animals exhibit weight loss, lowered male fertility, elevated blood sugar, atherosclerosis and nerve degeneration. Deficiency symptoms in humans include intolerance of alcohol and a decreased ability to use insulin to help metabolize blood sugar, a pre-diabetic condition. Chromium supplementation, either as chromium chloride or as chromium picolinate, did not increase strength or improve body composition (in terms of increased muscle mass or decreased body fat) in male volunteers participating in an eight-week weight-training program. Possibly the beneficial effects of chromium can occur when people are deficient in chromium. Chromium supplementation can lower iron transport and distribution in the body, possibly placing the individual at risk for iron deficiency.

Optimum chromium intake

The chromium intake for optimum health isn't known. A safe and adequate dose is thought to be 50mcg to 200 mcg daily. Brewers yeast is the best food source. Other sources are liver, oysters, whole potatoes, egg yolks, prunes, mushrooms, wine, beer, meat and beets. Fruits are low in chromium; so are polished rice and bleached flour. Chromium levels in grains and vegetables depend upon the amount of chromium in the soil in which they were grown; however, chromium in vegetables isn't well absorbed. Surprisingly, Calcium-fortified breakfast cereals are often good sources of the mineral because added calcium contains chromium as a contaminant. Supplemental chromium is available as chromium chloride. When taken together with niacin, its effect on lowering blood lipids is significantly improved, and the combination is as effective as taking yeast glucose tolerance factor. Several organically complexed forms of chromium such as chromium picolinate may be more readily absorbed than chromium chloride as supplements.