Daily Archives: July 9, 2019

Vitamin A

Vitamin AJacquie Eubanks RN BSN

Vitamin A is a collective name for a group of fat soluble biomolecules known as retinol, retinal, and retinoic acid. Vitamin A participates in a variety of cellular activities and is considered an essential micronutrient required throughout life. Yet, vitamin A is not synthesized by the body and must be obtained through the diet or supplementation. Dietary sources of retinol or preformed vitamin A include eggs, fish oils and dairy products. As well, provitamin A carotenoids found in leafy greens, yellow vegetables and orange fruits must be converted by the body to retinol. Retinoic acid is the primary mediator of the biological actions of vitamin A, which is involved in vision, tissue maintenance, lipid metabolism, reproduction, embryonic development and growth. It is also involved in cellular differentiation, the process by which a cell becomes specialized in order to perform a specific function.

  • Retinol and its derivatives are required for the maintenance of the body’s biological barriers against infection, including the skin, eyes and the mucosal cells of the respiratory, digestive and genitourinary tracts. Retinols are necessary for the development of white blood cells and natural killer cells that play a major role in mounting an immune response. A deficiency in vitamin A leads to immunodeficiency and increased risks of infections and chronic disease. Deficiency is often associated with excess alcohol intake and dietary restrictions.
  • Retinal is a light absorbing metabolite necessary for both color and night vision. Because vitamin A helps to protect the cornea, it is essential for proper eyesight. In combination with other antioxidant vitamins, vitamin A appears to play a role in decreasing vision loss due to macular degeneration. Along with lutein, vitamin A may prolong vision in those suffering from retinitis pigmentosa. Poor night vision, vision loss and corneal ulcers may occur when there is a deficiency of vitamin A.
  • Retinoic acid is the active form of vitamin A, which functions as a hormone-like growth factor for epithelial cells, which line the outer surfaces of skin, organs and blood vessels and the inner surfaces of hollow organs, as well as many other cells and tissues. This form also maintains normal skin health, switching on genes that aid cell maturity.
  • ß-carotene provides a major plant source of optimal naturally occurring provitamin A, a precursor that is converted to retinol, contributing greatly to the body’s total vitamin A level. Like all carotenoids, beta-carotene performs as an effective antioxidant, protecting against free radicals and inhibiting the oxidation of other molecules. As oxidative stress is considered a key factor in cognitive decline, antioxidants may help reduce the risk of cognitive degeneration. Additionally, ß-carotene may help to reduce inflammation believed to be at the root of neurodegenerative and other chronic diseases, as well as inflammatory conditions such as rheumatoid arthritis and Crohn’s disease.

To recap, vitamin A promotes good vision health, supports immunity and white blood cell production, relieves inflammation, promotes and maintains skeletal and soft tissues, supports skin cell health and repair and is essential for reproduction, growth and development.  One fundamental fact about vitamin A is that it is required for both innate and adaptive immunity and is essential for normal immune function and antibody response. As vitamin A performs as an important fat-soluble vitamin as well as a potent antioxidant, sufficient vitamin A intake is crucial to the maintenance of overall health and function.

Professional Supplement Center carries these and other high quality supplements in support of overall health and function:

Natural Beta...Natural Beta Carotene Mulsion by Professional Complementary Health Formulas: Based on clinical and research information, this product is formulated with selectively sourced, concentrated beta-carotene. ß-carotene is provided in an easy to swallow perle format to maximize absorption and nutrient utilization. Gluten and soy free vegetarian formulation.

 

Vitamin A 10,000 I.U...

Vitamin A 10,000 IU by Douglas Laboratories®: Each softgel provides 10,000 IU of vitamin A (as vitamin A palmitate) in cod liver oil in support of vision, cellular and immune health.

 

Beta Carotene (with...Beta Carotene (with mixed carotenoids) by Pure Encapsulations®: This hypoallergenic supplement is formulated with provitamin A as beta carotene blended with alpha-carotene, zeaxanthin and lutein in support of antioxidant defenses. Gluten free, Non-GMO formulation.

 

A-Potene 25,000 IUA-Potene™ 25,000 IU by Douglas Laboratories®: Each softgel provides 25,000 IU of provitamin A as beta-carotene. Free of gluten, wheat, soy, dairy, corn, sodium, starch, sugar and artificial coloring, preservatives and flavoring.

 

Vitamin A Dry 5,000...Vitamin A Dry 5,000 IU by Solgar®: This convenient dry tablet provides 5,000 IU of vitamin A (as retinyl palmitate) per serving in support of eye, vision, skin and immune health. Free of gluten, wheat, dairy, soy, yeast, sugar, sodium and artificial flavors, sweeteners, preservatives and colorings.

References:
Immunity in Depth. https://lpi.oregonstate.edu/mic/health-disease/immunity
The biological significance of vitamin A in humans: A review of nutritional aspects and clinical considerations. https://www.researchgate.net/publication/225187885_The_biological_significance_of_vitamin_A_in_humans_A_review_of_nutritional_aspects_and_clinical_considerations
ß-Carotene Is an Important Vitamin A Source for Humans. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3139236/
Carotenoids—Antioxidant Properties. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5836018/