the chemical breakdown of complex substances into simpler ones.


the speeding up of a chemical reaction by a substance, needed in only a small amount, that is not itself permanently changed in the reaction.


a protein that carries the majority of the copper in the blood.


the fluid secreted by the mammary gland for the first few days following parturition.

Continuance rate

in this report, the percentage of women who initiated breastfeeding who were still breastfeeding when their infants reached 6 months of age.


in this report, the distension of the breast with milk.


microorganisms that cause intestinal disease.


proteins that serve as organic catalysts.

Exclusive breastfeeding

consumption of human milk as the sole source of energy.

Femoral region

the thigh.


an adhesive glycoproprotein.

Glutathione peroxidase

a selenium-containing enzyme that reduces toxic hydrogen peroxide formed within the cell.

Hemorrhagic disease of the newborn

Syndrome in newborn period caused by vitamin K deficiency.


control of the immune response by mechanisms such as the immunoglobulin idiotype-antiidiotype network.


a substance that causes or stimulates the start of an activity.

Lactation performance

degree of success of breastfeeding, as determined by measurements such as milk volume, milk composition, duration of breastfeeding, and infant growth.

Lacteal cells

cells within the mammary gland that collect and produce the nutrients that make up milk.


an iron-binding protein found in secretions such as milk and in specific granules of neutrophils.


the onset of copious milk secretion shortly after parturition.

Lactogenic hormones

hormones that stimulate the development and growth of the mammary glands.

Lactose intolerance

a condition in which the intestinal enzyme lactase, which breaks down lactose to glucose plus galactose, is lacking; this may lead to cramps and diarrhea after consumption of certain lactose-containing foods (e.g., milk).

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