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Chromium Herb Description - Drug Interactions, Dosage and Some of its Useful Properties
Common Trade Names
Beer Belly Busters, Body Lean, Chromaslim, Chroma Ultra Chromium Picolinate, Chromax, Chromax II, Chromium Picolinate High Potency, Chromium Picolinate Yeast Free, GTF Chromium Picolinate, Medislim, Perfect Chromium Picolinate, Protecol, The Chromium Picolinate Solution
Common Forms
Available in various strengths and dosage forms alone and in combination with vitamin and mineral preparations.
Source
Chromium is found in beer, brewer's yeast, mushrooms, oysters, and some meats (especially kidneys). Some sources recommend a daily chromium intake of 50 to 200 mcg. Only small percentages (0.5% to 2%) of dietary chromium are actually absorbed . Absorption does appear to be related to the salt form of chromium ingested, with the picolinate salt being the favored carrier of chromium. Average serum chromium levels in normal subjects range from 0.1 to 0.3 mcg/L .
Chemical Components
Chromium in the 3+ oxidation state is an essential trace mineral. It is synthesized endogenously by a pyridine-2-carboxylic acid metabolite of tryptophan. Picolinic acid is a natural ligand that is an isomer of nicotinic acid.
Actions
Studies in animals suggest that chromium is widely distributed in the body and tends to accumulate in tissues, with a mean terminal elimination half-life exceeding 80 days (independent of dose). Early evidence suggests that chromium is necessary in the body for certain biochemical reactions to take place. Most literature appears to link chromium with a role in maintaining adequate glucose homeostasis. Interestingly, patients receiving long-term total parenteral nutrition who eventually developed glucose intolerance, insulin resistance, weight loss, and other disturbances mimicking syndrome X were reversed with LV. administration of chromium chloride .
Reported Uses
Chromium has been claimed to possess anabolic properties. It has been suggested to be useful for many varied conditions and situations: improving glucose utilization, increasing lean body mass, reducing fat mass, increasing energy, enhancing mood, improving vision, conditioning gums, curing acne, preventing insomnia, curbing addiction, improving psoriasis, preventing osteoporosis, and increasing longevity.
Several studies have pursued a role for chromium in diabetes. It is believed that chromium increases the rate of internalization of insulin within cells by improving cell membrane fluidity. The majority of evidence does suggest that chromium can lower fasting blood glucose levels . However, the most recent randomized, controlled, double-blind trials refute the fact that chromium (220 mcg/day) has any effect on fasting blood glucose or Hgb-A1C levels .
Chromium has been evaluated several times for its purported effect on body composition. Several studies suggest that chromium supplementation (200 to 300 mcg/day) for 2 to 3 months produces beneficial changes in body composition. Although not all studies found positive benefits with the same parameters, such changes as increases in lean body mass and body composition index and decreases in body fat and body mass index have been reported . Again, some additional controlled, doubleblind trial evidence is in conflict with the former data (Walker et a!., 1998). Even the most recent data, a randomized, placebo-controlled, double-blind trial evaluating the effect of chromium supplementation on resistance training in 18 men, failed to find a benefit of chromium on parameters of muscle size, strength, power development, or lean body mass. Resistance training devoid of chromium supplementation had significant and independent effects on these measurements .
Some trials have reported beneficial changes in the lipid profile of patients. Doses in the range of 600 mcg/day appear to produce the most favorable results, although smaller doses also have been evaluated. Patients who are documented to be chromium deficient may be the best candidates for chromium supplementation to improve their lipid profiles.
Although conflicting data exist, a trial of 19 nonobese subjects receiving 1,000 mcg/day of chromium or placebo for 8 weeks failed to identify any significant difference between chromium and placebo in study parameters measuring serum lipid levels, body composition, and insulin sensitivity .
Dosage
Dosing recommendations vary considerably, depending on the source. No consensus exists. Typically, adults are recommended to receive 200 to 400 mcg/day. Patients who potentially dispose of more chromium, elderly patients, diabetics, bodybuilders, and patients with hyperlipidemia are suggested to receive as much as 600 mcg/day. Other references suggest no more than 300 mcg/day. Doses used most commonly in clinical trials range from 200 to 400 mcg/day.
Adverse Reactions
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CNS: cognitive impairment.
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GI: diarrhea, epigastric discomfort, flatulence, nausea.
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GU: renal failure (1,000 mcg/day;).
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Hematologic: anemia.
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Hepatic: hepatic failure (1,000 mcg/ day;).
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Musculoskeletal: rhabdomyolysis.
Interactions
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Antacids: May bind dietary chromium, impairing chromium absorption. Stagger doses of both agents to minimize potential interaction.
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Antibiotics known to bind cationic compounds (fluoroquinolones, tetracyclines): May bind chromium, decreasing absorption of the antibiotic. Space administration of both drugs or discontinue chromium supplementation during antibiotic therapy.
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Vitamin C: May enhance chromium absorption. Consider lower dose of chromium.
Contraindications And Precautions
Chromium is contraindicated in patients who are hypersensitive to chromium or the picolinate salt. Avoid consumption of chromium in excess of the RDA during pregnancy.
Special considerations
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Some evidence suggests that most Americans consume less than the RDA of chromium.
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Doses roughly equivalent to 600 mcg/day in humans produced chromosomal damage in Chinese hamster ovary cells .
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The American Dietetic Association could not support the use of chromium for diabetics in a position paper.
Commentary
Clinical trial data evaluating chromium supplementation in diabetes, manipulation of body composition, and cholesterol reduction are fraught with conflict. Many early studies suffer from a small number of subjects, lack of a control group, inadequate description of subjects, missing information, and the use of imprecise or subjective measurements. More recent, rigorously designed and carefully controlled trials have failed to find significant differences that favor chromium supplementation. Chromium's unique pharmacokinetic profile might predispose subjects to acute or chronic chromium intoxication if higher than normal quantities are ingested over a long period. Most studies have been of short duration (less than or equal to 3 months). Subsequently, doses in excess of the RDA (50 to 200 mcg/day) are not recommended.
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