Chapter 10

Iodine deficiency disrupts thyroid function and can cause goiter

goiter, an enlargement of the thyroid gland.

trace minerals similar to minerals but trace minerals ar less required in body

trace minerals -

Circulate freely in the blood, Found in both plant and animal foods, Absorbed mostly in the small intestine

Trace minerals are found in both animal and plant foods, but the bioavailability varies

Bioavailability is influenced by: Form of the food Nutrition status Age Pregnancy

Iodine is an essential component of thyroid hormone

thyroid gland, thyroid stimulating hormone, thyroid hormones

Hypothyroidism

  • Slow metabolic rate
  • Goiter

Cretinism

  • Mental retardation, deafness, stunted growth, and other abnormalities
  • Mild forms of iodine deficiency in pregnancy can affect neurological development

The RDA for iodine for adults is 150 micrograms

to much iodine: causes goiter, hypothyroidism

Iron

Required for chemical processes

  • Energy metabolism
  • Immune response
  • DNA synthesis

Present in:

  • Heme iron

Ā Ā Ā Ā Ā Ā Ā -Hemoglobin

Ā Ā Ā Ā Ā Ā Ā -Myoglobin

  • Nonheme iron

Heme iron is a critical part of the ==hemoglobin (found in red blood cells)== protein

The iron-containing protein in muscle is ==myoglobin (found in muscle cells)==

Oxygen is carried by hemoglobin in blood and supplied by myoglobin in muscle

Food sources

  • Heme in red meats, poultry, and fish
  • Nonheme in plant foods: beans, dried and grain products

Absorption

  • Increased by vitamin C, acid, and meat
  • Decreased by soy protein, phytates, and polyphenols, as well as by calcium intake

Iron-deficiency anemia

  • Caused by blood loss
  • Insufficient iron intake
  • High-risk groups

Excess iron intake causes adverse effects in adults and can be lethal in children

Zinc (Zn) is required for the function of more proteins in the body than any other mineral

Required for almost every essential process in the body

  • Regulation of protein synthesis
  • Reproduction
  • Cell division
  • Growth and development
  • Immune responses
  • Neurological functions

Zinc (Zn) supplementation in at-risk children may help improve immunity, growth, and development

Copper

Functions

  • Cofactor in oxygen-dependent enzymes
  • Energy metabolism
  • Formation of connective tissues
  • Regulation of iron storage and transport
  • Antioxidant functions
  • May slow progression of age-related macular degeneration

factors:

Malabsorption from other conditions Gastric bypass surgery Excessive zinc intake

About two dozen selenium-containing human proteins have been identified

Essential for normal growth, development, and metabolism

deficiency increases risk of vitamin E

Low selenium status

  • Increases risk for a particular form of heart disease
  • May increase risk of some cancers
  • Decreases immune function

Fluoride has a well-established role in preventing cavities through hardening and maintaining tooth enamel

Excess intake can cause fluorosis of teeth and bone

Manganese

  • Cofactor for enzymes in antioxidant function, energy metabolism, bone development, and neurotransmitter production

Molybdenum

  • Cofactor for four enzymes in metabolism

Chromium (Cr)

  • Evidence is lacking for claims, including that it enhances the action of insulin in blood glucose control

ultratrace minerals

Animal data suggest these may be important: Arsenic (As) Boron (B) Nickel (N) Silicon (Si) Vanadium (V)

Ā