Vitamin D Council Glossary

# A B C D E F G H I J–K L M N O P R S T U V
Induced inadvertently by a physician, surgeon, medical treatment, or diagnostic procedure.
Of unknown cause or origin.
Neuroendocrine-immune system axis that is crucial for protective immunity to mycobacterium in humans and mice.
Immune system
Collection of mechanisms within an organism that protects against infection by identifying and killing pathogens and tumor cells. The immune system has two main components:
  • Innate immune system: Cells and mechanisms found in all classes of plant and animal life which provide immediate defense against infection in a non-specific manner.
  • Adaptive immune system: System, found only in jawed vertebrates, which provides a pathogen- and antigen-specific response. The cells of the adaptive immune system are called lymphocytes, of which T cells and B cells are the major types.
Having the ability to alter or regulate one or more immune functions.
Inhibits or prevents activity of the immune system. Immunosuppressive substances are used in the treatment of autoimmune diseases, some inflammatory diseases, and for preventing transplant organ rejection.
Hormone that is secreted by groups of cells within the pancreas (called islet cells) in response to a detected increase in blood sugar.
International Unit (IU)
A unit of measurement for the amount of a substance, based on measured biological activity. For vitamin D, 1.000 IU is equal to 0.025 µg (micrograms) cholecalciferol or ergocalciferol.
Institute of Medicine (IOM)
Component of the United States' National Academy of Sciences whose mission is to "serve as adviser to the nation to improve health."
Introns are DNA regions in a gene that are not translated into proteins.
Ischemia (also spelled ischaemia)
Restriction in blood supply that results in damage to, or dysfunction of, tissue.
Different form of a protein that may be produced from different genes, or from the same gene by alternative splicing.
Molecule with the same chemical formula of another, but different arrangement of atoms.

*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.