vitamin

(noun)

any of a specific group of organic compounds essential in small quantities for healthy human growth, metabolism, development, and body function

Related Terms

Examples of vitamin in the following topics:

  • Food Requirements and Essential Nutrients

    • Vitamins and minerals are substances found in the food we eat.
    • Each vitamin has its own special role to play.
    • Some fat-soluble vitamins include vitamin A, vitamin K, vitamin D, and vitamin E.
    • Unlike fat-soluble vitamins, they can be destroyed by heat.
    • Some water-soluble vitamins include vitamin B6, vitamin B12, vitamin C, biotin, folic acid, niacin, and riboflavin.

  • Digestion and Absorption

    • Intestinal bacteria also play a role in synthesizing vitamin B and vitamin K as well as metabolizing bile acids, sterols and xenobiotics.
    • Vitamins can be either water-soluble or lipid-soluble.
    • Fat-soluble vitamins are absorbed in the same manner as lipids.
    • It is important to consume some amount of dietary lipid to aid the absorption of lipid-soluble vitamins.
    • Water-soluble vitamins can be directly absorbed into the bloodstream from the intestine.

  • Control of Metabolism Through Enzyme Regulation

    • The most common coenzymes are dietary vitamins.
    • Vitamin C is a coenzyme for multiple enzymes that take part in building collagen, an important component of connective tissue.
    • Vitamins are important coenzymes or precursors of coenzymes and are required for enzymes to function properly.
    • Multivitamin capsules usually contain mixtures of all the vitamins at different percentages.

  • Intracellular Hormone Receptors

    • Other lipid-soluble hormones that are not steroid hormones, such as vitamin D and thyroxine, have receptors located in the nucleus.
    • For example, the active vitamin D metabolite, calcitriol, mediates its biological effects by binding to the vitamin D receptor (VDR), which is principally located in the nuclei of target cells.

  • Electrons and Energy

    • The principal electron carriers we will consider are derived from the vitamin B group, which are derivatives of nucleotides.
    • Nicotinamide adenine dinucleotide (NAD) is derived from vitamin B3, niacin.
    • Similarly, flavin adenine dinucleotide (FAD+) is derived from vitamin B2, also called riboflavin.

  • Platelets and Coagulation Factors

    • Many of the clotting factors require vitamin K to function.
    • Vitamin K deficiency can lead to problems with blood clotting.

  • Digestive System: Small and Large Intestines

    • It is here that bile salts and vitamins are absorbed into blood stream.
    • The large intestine reabsorbs water from undigested food material and processes waste material; although it is also capable of absorbing vitamins that are synthesized by the normal microflora housed herein.
    • The liver also processes the vitamins and fats along with synthesizing many plasma proteins.

  • Steroids

    • Cholesterol is the most common steroid and is mainly synthesized in the liver; it is the precursor to vitamin D.

  • Bone Remodeling and Repair

    • Normal bone growth requires vitamins D, C, and A, plus minerals such as calcium, phosphorous, and magnesium.

  • Digestive Systems

    • Both of these are an important source of vitamins and minerals, as well as carbohydrates, which are broken down through digestion for energy.