Vitamin A is an essential micronutrient required to maintain vision, the immune response, barrier function, growth and differentiation, male and female reproduction, and fetal development. It is acquired from the diet either as preformed vitamin A from animal foods or as provitamin A carotenoids ...
Low vitamin A levels may occur in people who eat certain traditional diets that contain few foods with vitamin A. People in developing countries may also have difficulties accessing foods with vitamin A or provitamin A carotenoids. Low vitamin A is also more likely with certain groups of people ...
H. 2012. Mechanisms involved in the intestinal absorption of dietary vitamin A and provitamin A carotenoids. Biochim. Biophys. Acta 1821: 70-77.Harrison EH. Mechanisms involved in the intestinal ab- sorption of dietary vitamin A and provitamin A carote- noids. Biochim Biophys Acta. 2012;1821:...
Learn more about VITAMIN A uses, effectiveness, possible side effects, interactions, dosage, user ratings and products that contain VITAMIN A.
Adequate intake of vitamin A usually can be accomplished through consumption of foodstuffs that contain preformed vitamin A (e.g., liver, dairy products, fish) and provitamin A carotenoids (e.g., darkly colored fruits and vegetables).Adequate intake (AI) established for infants ≤6 months of ...
FROM DIETARY VITAMIN A TO CIRCULATING SERUM RETINOL The precursors of atRA have to be obtained from the diet, either as retinyl esters from animal sources or provitamin A carotenoids from plants, mainly as β-carotene (reviewed in Refs. 15 and 16, and in this thematic series by Harrison and...
Vitamin A is obtained through the diet in two forms: preformed vitamin A (retinol) and provitamin A carotenoids (like beta-carotene). Beta-carotene appears to be the safer source of vitamin A. The Institute of Medicine of the National Academies’ Food and Nutrition Board recommends against beta...
Mechanisms involved in the intestinal absorption of dietary vitamin A and provitamin A carotenoids. Biochim. Biophys. Acta 2012, 1821, 70–77. [Google Scholar] [CrossRef] Senoo, H.; Imai, K.; Mezaki, Y.; Miura, M.; Morii, M.; Fujiwara, M.; Blomhoff, R. Accumulation of vitamin A...
Vitamin A is a fat-soluble micronutrient present in three forms, including retinol, retinal, and retinoic acid. Retinol exists in the form of retinyl ester in some foods with animal sources, such as liver, eggs, dairy products, and oily fish; or in the form of provitamin A carotenoids as...
Vitamin A exist in the form of retinoids and carotenoids. Retinol Beta-carotene Picture 1. Beta-carotene (right) can be split into two molecules of retinol (left) in your liver 1. RETINOIDS: RETINOL, RETINAL (PREFORMED VITAMIN A) Preformed vitamin A (retinol) naturally occurs only in animal...