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Overview |
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Chromium is an essential trace element for humans. Chromium in tissue is
highest during infancy and decreases steadily with age. The average adult body
contains about 600 mcg of chromium. Absorption occurs primarily in the jejunum
and is affected by interactions with other metals, such as zinc, iron, and
vanadium, and chelating agents, such as oxalate and phytate. After absorption,
transferrin binds trivalent chromium and transports it to body tissues. Absorbed
chromium is excreted primarily in the urine, with small amounts lost in hair,
perspiration, and bile. Unabsorbed chromium (>99%) is lost in the feces.
Chromium must be converted to a biologically active form for physiological
function. Glucose tolerance factor (GTF), a biologically active form isolated
from brewer's yeast, contains chromium (III), nicotinic acid, and the amino
acids glycine, glutamic acid, and cysteine. GTF potentiates insulin's actions
and therefore influences carbohydrate, lipid, and protein metabolism. It works
with insulin to facilitate glucose uptake, regulate blood sugar levels, and
stimulate protein synthesis. The exact nature of the chromium-insulin
interaction is unknown. Chromium may potentiate insulin action through direct
action on insulin or its receptor, or it may regulate the synthesis of a
molecule that potentiates insulin action. In clinical studies, GTF chromium has
been shown to potentiate the effects of insulin and decrease serum cholesterol
and triglycerides.
It is estimated that as many as 90% of all American diets are low in
chromium. Individuals often consume less than the suggested minimum intake for
chromium. The trend toward consuming highly processed foods may be a major
contributing factor to this problem; appreciable losses of chromium occur in the
refining of foods. Children with protein-calorie malnutrition, diabetics, and
older individuals may be especially susceptible to chromium deficiency.
Stressors such as elevated simple sugars, strenuous physical exercise or work,
infection, and physical trauma may increase the loss of chromium, thereby
increasing the need for chromium. Symptoms of chromium deficiency include
glucose intolerance, elevated circulating insulin, glycosuria, fasting
hyperglycemia, impaired growth, decreased longevity, elevated serum cholesterol
and triglycerides, increased incidence of aortic plaques, peripheral neuropathy,
brain disorders, decreased fertility and sperm count, negative nitrogen balance,
and decreased respiratory quotient. |

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Dietary Sources |
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- Brewer's yeast (best dietary source when grown on chromium-rich
medium)
- Lean meats (especially processed meats)
- Cheeses
- Pork kidney
- Whole-grain breads and cereals
- Molasses
- Spices
- Some bran cereals
Vegetables, fruits, and most refined and processed foods (except for some
processed meats, which contain high amounts of chromium) contain low amounts of
chromium. Hard tap water can supply 1% to 70% of one's daily intake. Cooking in
stainless steel cookware increases the chromium content of
food. |

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Constituents/Composition |
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Chromium is a white, hard, brittle metal that occurs in any oxidation state
from –2 to +6. Trivalent chromium is the most stable
and biologically active oxidation state and forms compounds with other organic
compounds. |

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Commercial
Preparations |
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Chromium is available commercially in several forms, including chromium
polynicotinate, chromium picolinate, chromium-enriched yeast, and chromium
chloride. Chromium is available in multivitamins and alone in tablet and capsule
forms. Daily preparation doses are typically between 15 and 200 mcg chromium in
multivitamins. |

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Therapeutic Uses |
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Diabetes. Chromium supplementation may improve glucose tolerance in healthy
individuals and Type II diabetics with low chromium levels, and older
individuals with abnormal glucose tolerance. Not all healthy individuals show a
response to chromium supplementation. Individuals with low chromium levels
appear to benefit the most from supplementation.
Poor dietary intake of chromium results in impaired glucose tolerance and
symptoms similar to those of Type II diabetes mellitus. Individuals with
marginally elevated blood glucose concentrations may benefit from chromium
supplementation. One study assessed the effects of chromium supplementation (200
mcg chromium chloride per day) on 20 normal subjects with marginally impaired
glucose tolerance. By the end of the three-month trial, 18 of the 20 subjects
exhibited significant improvement in glucose tolerance.
Supplementation with chromium has also been shown to improve glucose
tolerance in some diabetic patients. There is some indication that Type II
diabetics may have an increased requirement for chromium. In one study, diabetic
patients with severe complications, such as retinopathy and nephropathy, showed
lower blood concentrations of chromium.
Older individuals are more susceptible to low tissue chromium levels,
abnormal glucose tolerance, and increased incidence of diabetes and
cardiovascular disease. Several studies have examined the correlation between
low chromium levels and impaired glucose tolerance. In one clinical study,
chromium supplementation improved glucose tolerance in 50% of older subjects
(over age 70). Older individuals with mild abnormalities in glucose metabolism
appear to benefit more from supplementation than those with extreme
diabetic-like abnormalities in glucose intolerance.
Chromium is also used to treat the following conditions:
- Hypoglycemia. Chromium deficiency may be an underlying contributing
factor of hypoglycemia in some individuals. Supplementation with 200 mcg of
chromium improves the symptoms of hypoglycemia in some individuals.
- Cardiovascular disease. A low amount of chromium in the diet is
associated with increased blood cholesterol and increased risk of developing
cardiovascular disease. Supplementation with chromium has been shown to increase
HDL cholesterol and lower triglyceride and total cholesterol levels in diabetics
and in individuals with impaired glucose tolerance.
- Glaucoma. Chromium affects insulin receptors in the eye. There is a
strong association between chromium deficiency and increased risk of
glaucoma.
- Obesity. Preliminary evidence suggests that chromium supplementation
may help reduce body fat and increase lean body mass in some individuals.
Chromium's ability to increase insulin sensitivity may explain these effects.
- Osteoporosis. Chromium picolinate has been shown to decrease urinary
excretion of calcium and hydroxy-proline in women, and may help preserve bone
density in postmenopausal women.
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Dosage Ranges and Duration of
Administration |
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There are no RDAs established for chromium. The estimated safe and adequate
daily dietary intakes of chromium are as follows:
- Infants birth to 6 months: 10 to 40 mcg
- Infants 6 to 12 months: 20 to 60 mcg
- Children 1 to 3 years: 20 to 80 mcg
- Children 4 to 6 years: 30 to 120 mcg
- Children 7 to 10 years: 50 to 200 mcg
- 11+ years: 50 to 200 mcg
Dosage for disease prevention and treatment is typically 200 mcg chromium one
to three times a day. |

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Side
Effects/Toxicology |
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Excess intake or tissue accumulation of chromium can inhibit the
effectiveness of insulin. |

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Warnings/Contraindications/Precautions |
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Hexavalent chromium is more toxic than trivalent. Industrial exposure to high
amounts of chromium, usually airborne, can result in toxicity symptoms,
including allergic dermatitis, skin ulcers, and bronchogenic carcinoma.
Trivalent chromium, the form found in foods, is poorly absorbed; thus, extremely
high amounts are necessary to attain toxic levels. Gastric irritation can occur
at extremely high doses. |

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Interactions |
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Biguanide
Antidiabetic Agents;
Insulin
Preparations;
Sulfonylureas
A total of 115 patients with either Type I or Type II diabetes who were
treated with chromium (200 mcg/day) required lower doses of insulin,
sulfonylurea drugs, and metformin (Ravina and Slezack 1993). The glycemic
response to chromium treatment was greater for patients with Type II diabetes
(57.2%). Chromium picolinate may benefit patients with Type II diabetes by
increasing insulin sensitivity and stimulating insulin receptor sites (McCarty
1998). Calcium
Carbonate
Administration of 1 mL antacid suspension of calcium carbonate (150 mg) prior
to treatment with 20 uCi 51chromium chloride minimized accumulation
of chromium in the kidneys, testes, and spleen in male rats (Seaborn and
Stoecker 1990). These findings are supported by another study with female rats
given antacid (40 mg) by gastric intubation (0.5 mL) followed orally by 55 uCi
51chromium chloride; chromium absorption was hindered by pretreatment
with antacid (Davis et al. 1995). |

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References |
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Anderson RA, Cheng N, Bryden NA, et al. Elevated intakes of supplemental
chromium improve glucose and insulin variables in individuals with type 2
diabetes. Diabetes. 1997;46:1786-1791.
Anderson RA, Polansky MM, Bryden NA, Bhathena SJ, Canary JJ. Effects of
supplemental chromium on patients with symptoms of reactive hypoglycemia.
Metabolism. 1987;36:351-355.
Bahadori B, Wallner S, Schneider H, Wascher TC, Toplak H. Effect of chromium
yeast and chromium picolinate on body composition of obese, non-diabetic
patients during and after a formula diet. Acta Med Austriaca.
1997;24:185-187.
Davis ML, Seaborn CD, Stoecker BJ. Effects of over-the counter drugs on
51chromium retention and urinary excretion in rats. Nutr Res.
1995;15:201-210.
Friedman E, ed. Biochemistry of the Essential Ultratrace Elements. New
York, NY: Plenum Press; 1984.
Fujimoto S. Studies on the relationships between blood trace metal
concentrations and the clinical status of patients with cerebrovascular disease,
gastric cancer, and diabetes mellitus. Hokkaido Igaku Zasshi.
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Krause MV, Mahan LK. Food, Nutrition, and Diet Therapy. 7th ed.
Philadelphia, Pa: WB Saunders Co; 1984.
McCarty MF. Complementary measures for promoting insulin sensitivity in
skeletal muscle. Med Hypotheses. 1998;51(6):451-464.
McCarty MF. Anabolic effects of insulin on bone suggests a role for chromium
picolinate in preservation of bone density. Med Hypotheses.
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Murray MT, Pizzorno JE. Encyclopedia of Natural Medicine. 2nd ed.
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Ravina A, Slezack L. Chromium in the treatment of clinical diabetes mellitus.
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Seaborn CD, Stoecker BJ. Effects of antacid or ascorbic acid on tissue
accumulation and urinary excretion of chromium-51. Nutr Res.
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Shils ME, Olsen JA, Shike M, eds. Modern Nutrition in Health and
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Somer E. The Essential Guide to Vitamins & Minerals. New York, NY:
HarperCollins Publishers; 1992.
Urberg M, Zemel MB. Evidence for synergism between chromium and nicotinic
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Wilson BE, Gondy A. Effects of chromium supplementation on fasting insulin
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Copyright © 2000 Integrative Medicine
Communications This publication contains
information relating to general principles
of medical care that should not in any event be construed as specific
instructions for individual patients. The publisher does not accept any
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The reader is advised to check product information (including package inserts)
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interactions, and contraindications before administering any drug, herb, or
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