Author: Glossary
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Minerals, ultra-trace
Those mineral salts present in the body, and required in the diet, in extremely small amounts (parts per thousand million or less); known to be dietary essentials, although rarely if ever a cause for concern since the amounts required are small and they are widely distributed in foods and water.
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Minerals, trace
Those mineral salts present in the body, and required in the diet, in small amounts (parts per million). An element present in minute quantities which is essential to the life of an organism.
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Mineral salts
The inorganic salts, including sodium, potassium, calcium, chloride, phosphate, sulphate, etc. So called because they are (or originally were) obtained by mining.
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Milli
Prefix for units of measurement, one thousandth part (i.e. 10¯³); symbol m. A tenth of a cent or one thousandth of a dollar. Used to assess the rate of property taxes.
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Mid-upper-arm-circumference (MUAC)
A rapid way of assessing nutritional status, especially applicable to children.
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Microbiological assay
Method of measuring compounds such as vitamins and amino acids, using microorganisms. The principle is that the organism is inoculated into a medium containing all the growth factors needed except the one under examination; the rate of growth is then proportional to the amount of this nutrient added in the test substance.
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Methylmalonic acid
An intermediate in the metabolic turnover of succinic acid, this substance typically accumulates in conditions of vitamin B12 deficiency, and can be measured in serum or urine, as a functional index of vitamin B12 status.
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3-methyl-histidine
Derivative of the amino acid, histidine, found mainly in the contractile proteins of muscle (myosin and actin).
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Methaemoglobin
Oxidised form of haemoglobin (unlike oxyhaemoglobin, which is a loose and reversible combination with oxygen) which cannot transport oxygen to the tissues. Present in small quantities in normal blood, increased after certain drugs and after smoking; found rarely as a congenital abnormality (methaemoglobinaemia). It can be formed in the blood of babies after consumption of…
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Metaphosphoric acid
A form of phosphoric acid which is used as a preservative for vitamin C (ascorbic acid) because its addition to biological fluids, such as serum or urine, lowers the pH and chelates (i.e. inactivates) the pro-oxidant metal ions such as ferrous and cupric ions.