Six macrominerals are required by people in gram amounts.
Four cations: Sodium, potassium, calcium, and magnesium
Two accompanying anions: Chloride and phosphorus
Daily requirements range from 0.3 to 2.0 g. Bone, muscle, heart, and brain function depend on these macrominerals.
(See also Water and Sodium Balance.)
Nine trace minerals (microminerals) are required by people in minute amounts:
Chromium
Copper
Fluorine
Iodine
Iron
Manganese
Molybdenum
Selenium
Zinc
Dietary guidelines for trace minerals have been determined (see table Guidelines for Daily Intake of Trace Minerals). All trace minerals are toxic at high levels; some minerals (chromium) may be carcinogens. It is not clear whether chromium should be considered an essential (required) trace element (1).
Trace mineral deficiencies (except for iodine, iron, and zinc) do not often develop spontaneously in adults on ordinary diets; infants are more vulnerable because their growth is rapid and intake varies.
Trace mineral imbalances can result from hereditary disorders (eg, hemochromatosis, Wilson disease), kidney dialysis, parenteral nutrition, restrictive diets prescribed for people with inborn errors of metabolism, or various popular diet plans.
Мікроелементи
Nutrient | Principal Sources | Functions | Some Effects of Deficiency and Toxicity |
|---|---|---|---|
Chromium | Liver, processed meats, whole-grain cereals, nuts | Promotion of glucose tolerance | Deficiency: Possibly impaired glucose tolerance Toxicity: Skin, lung, and gastrointestinal tract irritation after exposure to hexavalent chromium (CrO3) in the workplace; may cause perforation of the nasal septum and lung carcinoma |
Copper | Organ meats, shellfish, nuts, dried legumes, dried fruits, whole-grain cereals, peas, cocoa, mushrooms, tomato products | Enzyme component, hematopoiesis, bone formation | Deficiency: Anemia in undernourished children; can be present in Menkes (kinky-hair) syndrome Toxicity: Copper poisoning; can be present in Wilson disease |
Fluorine | Seafood, tea, fluoridated water (sodium fluoride 1.0–2.0 parts per million) | Bone and tooth formation | Deficiency: Predisposition to dental caries, possibly osteoporosis Toxicity: Fluorosis, mottling and pitting of permanent teeth, exostoses of spine |
Iodine | Seafood, iodized salt, eggs, cheese, drinking water (content varies) | Thyroxine (T4) and triiodothyronine (T3) synthesis, development of fetus | Deficiency: Simple (colloid, endemic) goiter, congenital hypothyroidism with deaf-mutism, impaired fetal growth and brain development (cretinism) Toxicity: Hyperthyroidism or hypothyroidism |
Iron | Many foods (except dairy products)—soybean flour, beef, kidney, liver, fish, poultry, beans, clams, molasses, enriched grains and cereals (bioavailability variable in plant sources) | Hemoglobin and myoglobin formation, cytochrome enzymes, iron-sulfur proteins | Deficiency: Anemia, pica, glossitis, angular cheilosis Toxicity: Cirrhosis, diabetes mellitus, skin pigmentation; can be present in hemochromatosis |
Manganese | Whole-grain cereals, pineapple, nuts, tea, beans, tomatoes | Healthy bone structure Component of manganese-specific enzymes: glycosyltransferases, phosphoenolpyruvate carboxykinase, manganese-superoxide dismutase | Deficiency: Questionable Toxicity: Neurologic symptoms resembling those of parkinsonism or Wilson disease |
Molybdenum | Milk, legumes, whole-grain breads and cereals, dark green vegetables | Component of coenzyme for sulfite oxidase, xanthine dehydrogenase, and aldehyde oxidase | Deficiency: Tachycardia, headache, nausea, obtundation (sulfite toxicity) |
Selenium | Meats, seafood, nuts, plant-based foods (selenium content varying with soil concentration) | Component of glutathione peroxidase and thyroid hormone iodinase | Deficiency: Keshan disease (viral cardiomyopathy), muscle weakness Toxicity: Hair loss, abnormal nails, nausea, dermatitis, peripheral neuropathy |
Zinc | Meat, liver, oysters, seafood, fortified cereals, peanuts, whole grains (bioavailability variable in plant sources) | Enzyme component, skin integrity, wound healing, growth | Deficiency: Impaired growth and delayed sexual maturation, hypogonadism, hypogeusia Toxicity: Red blood cell microcytosis, neutropenia, impaired immunity |
Керівництва зі щоденного споживання мікроелементів
Category | Age (year*) or Time Frame | Chromium (mcg) | Copper (mcg) | Fluoride (mg) | Iodine (mcg) | Iron (mg) | Manganese (mg) | Molybdenum (mcg) | Selenium (mcg) | Zinc (mg) |
|---|---|---|---|---|---|---|---|---|---|---|
Recommended daily intake | ||||||||||
Infants | 0.0–6 mo | 0.2 | 200 | 0.01 | 110 | 0.27 | 0.003 | 2 | 15 | 2 |
7 mo–1 yr | 5.5 | 220 | 0.5 | 130 | 11 | 0.6 | 3 | 20 | 3 | |
Children | 1–3 | 11 | 340 | 0.7 | 90 | 7 | 1.2 | 17 | 20 | 3 |
4–8 | 15 | 440 | 1 | 90 | 10 | 1.5 | 22 | 30 | 5 | |
Males | 9–13 | 25 | 700 | 2 | 120 | 8 | 1.9 | 34 | 40 | 8 |
14–18 | 35 | 890 | 3 | 150 | 11 | 2.2 | 43 | 55 | 11 | |
19–30 | 35 | 900 | 4 | 150 | 8 | 2.3 | 45 | 55 | 11 | |
31–50 | 35 | 900 | 4 | 150 | 8 | 2.3 | 45 | 55 | 11 | |
51+ | 30 | 900 | 4 | 150 | 8 | 2.3 | 45 | 55 | 11 | |
Females | 9–13 | 21 | 700 | 2 | 120 | 8 | 1.6 | 34 | 40 | 8 |
14–18 | 24 | 890 | 3 | 150 | 15 | 1.6 | 43 | 55 | 9 | |
19–30 | 25 | 900 | 3 | 150 | 18 | 1.8 | 45 | 55 | 8 | |
31–50 | 25 | 900 | 3 | 150 | 18 | 1.8 | 45 | 55 | 8 | |
51+ | 20 | 900 | 3 | 150 | 8 | 1.8 | 45 | 55 | 8 | |
Pregnant 14–18 | 29 | 1000 | 3 | 220 | 27 | 2.0 | 50 | 60 | 12 | |
Pregnant 19–30 | 30 | 1000 | 3 | 220 | 27 | 2.0 | 50 | 60 | 11 | |
Pregnant 31–50 | 30 | 1000 | 3 | 220 | 27 | 2.0 | 50 | 60 | 11 | |
Breastfeeding 14–18 | 44 | 1300 | 3 | 290 | 109 | 2.6 | 50 | 70 | 13 | |
Breastfeeding 19–30 | 45 | 1300 | 3 | 290 | 9 | 2.6 | 50 | 70 | 12 | |
Breastfeeding 31–50 | 45 | 1300 | 3 | 290 | 9 | 2.6 | 50 | 70 | 12 | |
* * Except where noted differently. | ||||||||||
NOTE: Recommended dietary allowances (RDAs) are shown in regular type. RDAs are set to meet the needs of 97 to 98% of people in a group. Adequate intakes (AIs) are shown in bold type. For healthy breastfed infants, AIs are the mean intake. For other groups, AIs are amounts believed to meet the needs of all people in the group, but because of lack of data, the percentage of people covered cannot be specified with confidence. | ||||||||||
NR = not recommended; ND = not determinable because of lack of data, so sources of intake should be limited to foods. | ||||||||||
Довідковий матеріал
1. Vincent JB: New evidence against chromium as an essential trace element. J Nutr 147(12):2212–2219, 2017. doi:10.3945/jn.117.255901
Додаткова інформація
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
U.S. Department of Agriculture: General resources on vitamins and minerals provided by the National Agricultural Library.
