Chromium
Chromium is an essential mineral that is involved primarily in the regulation of blood sugar metabolism. It is found in brewer’s yeast, calf liver, unrefined grains and cereals, and selected vegetables such as potatoes and green peppers. Blood levels of this mineral are very difficult to measure, and deficiencies correspondingly difficult to assess. Deficiencies are most commonly noted in impaired blood sugar tolerance and, in more severe cases, in hospitalized patients with unmanageable blood sugar levels that are unresponsive to insulin treatment. The most common result of massive doses of supplemental chromium appears to be kidney damage.
The Reference Daily Intake (RDI) for chromium currently used by the U.S. Food and Drug Administration is 120 mcg. The January 2001 report from the National Academy of Sciences
study on Dietary Reference Intakes did not establish an RDI for reasons of inadequate data, but has set an adequate intake (AI) of 35 mcg for adult men, and 25 mcg for adult women. A tolerable upper intake level (UL) for this mineral has not been established.
The most promising application of supplemental chromium appears to be in the management of mildly impaired blood sugar tolerance. Reports of use of this mineral in weight management and performance enhancement have been difficult to substantiate and require additional research.
CONTRAINDICATIONS:
- diabetics on oral or insulin medication should consult with their health care provider prior to using supplemental chromium
Copper
Copper is an essential mineral that functions primarily as a bound component of many enzymes required in numerous critical metabolic pathways. The best dietary sources of copper include oysters, various types of nuts, beans, whole grains and dark green vegetables. Copper deficiency is relatively uncommon, but has been associated with anemia, and depressed levels of high-density lipoproteins (HDL). Excess zinc supplementation has been known to interfere with copper absorption, as have large doses of vitamin C, though to a lesser extent. Reports of ill-effects of excess copper are also uncommon, but have been associated with nausea and vomiting in some individuals.
The Reference Daily Intake (RDI) for copper currently used by the U.S. Food and Drug Administration is 2000 mcg (2 mg). The January 2001 report from the National Academy of Sciences
study on Dietary Reference Intakes has set the Recommended Dietary Allowance (RDA) for copper at 900 mcg/day for adult men and women, and has established a tolerable upper intake level (UL) for this mineral of 10,000 mcg (10 mg)/day.
Although it has been suggested that supplemental copper may play a role in the prevention or maintenance of numerous disorders, such as certain types of arthritis, heart disease and high cholesterol, there is insufficient proof to substantiate these claims at this time.
CONTRAINDICATIONS:
- Pregnant or nursing women, or adults administering this mineral to a child should first consult with their health care provider
- Women using oral contraceptives should also first seek professional medical advice prior to taking supplemental copper
- Anyone with Wilson's disease (abnormal copper accumulation) should not take copper
- Antacids containing aluminum or magnesium hydroxide are known to interfere with the absorption of copper, the regular use of which may cause copper deficiency
- The effect of many nonsteroidal anti-inflammatory drugs (NSAIDS), and many over-the-counter remedies, including those containing ibuprofen, may be dangerously enhanced in the presence of excess copper supplementation
Iodine
Iodine is an essential mineral that functions primarily in the support of the thyroid gland, enabling it to produce thyroid hormone, which in turn regulates metabolism throughout the rest of the body. The greatest natural concentration of iodine is found in sea water, kelp and seafood. In the U.S., iodine has been added to table salt for many years. Although relatively uncommon, iodine deficiency is responsible for goiter (abnormal enlargement of the thyroid gland). The use of supplemental iodine is recommended only to correct a deficiency of this nutrient.
The Reference Daily Intake (RDI) for iodine currently used by the U.S. Food and Drug Administration is 150 mcg. The January 2001 report from the National Academy of Sciences
study on Dietary Reference Intakes has set the Recommended Dietary Allowance (RDA) for iodine also at 150 mcg/day for adult men and women, and has established a tolerable upper intake level (UL) for this mineral of 1100 mcg (1.1 mg)/day.
CONTRAINDICATIONS:
- There are no known drug or supplement interactions with iodine.
Iron
Iron is an essential mineral that forms a portion of both hemoglobin and myoglobin, which bind and transport oxygen to cells throughout the body via the blood and provide oxygen to muscle tissue, respectively. This mineral is also involved in energy and DNA production, among other critical functions in the body. Iron is found in greatest concentration in red meats, fish, poultry and oysters in its highly-absorbable organic, or
heme form, and in dried fruits, leafy green vegetables, beans, nuts, and seeds, among others, in its less absorbable inorganic, or
non-heme form. Dietary iron deficiency is relatively uncommon, but deficiencies resulting from blood loss, or diseases affecting the proper formation of hemaglobin are more common. Iron supplementation is recommended only to correct anemias resulting from such deficiencies. Supplemental iron is not recommended for any other reason and, in fact, can lead to gastrointestinal and liver toxicity, among other problems, if consumed in excess.
The Reference Daily Intake (RDI) for iron currently used by the U.S. Food and Drug Administration is 18 mg. The January 2001 report from the National Academy of Sciences
study on Dietary Reference Intakes has set the Recommended Dietary Allowance (RDA) for iron at 8 mg/day for adult men and women (18 mg/day for premenopausal women), and has established a tolerable upper intake level (UL) for this mineral of 45 mg/day.
There have been reports that iron supplementation can improve athletic performance. While this may be true to some degree, apparently it is most effective only when the subjects are already somewhat deficient in iron, and there remains the risk of over consumption and toxicity.
CONTRAINDICATIONS:
- Individuals using deferoxamine should not take supplemental iron
- High doses of vitamin C can cause excessive iron absorption
- Some over-the-counter antacids may decrease iron absorption
- Large amounts of caffeine can decrease iron absorption
- Calcium, zinc, copper and manganese supplementation can interfere with iron absorption
- Iron supplements can interfere with the absorption of several classes of drugs, the most common of which include antibiotics in the tetracycline or quinolone classes, angiotensin-converting enzyme (ACE) inhibitors, several adrenergic agents (carbidopa, levodopa, methyldopa), and penicillamine, among others