Vitamin A is a general term of Vitamin A Retinol, retinal, beta-carotene, alpha-carotene, gamma-carotene, and beta-cryptoxanthin best known for its function for vision health and antioxidant scavenger and essential for growth and differentiation of a number of cells and tissues.
In a study of "Vitamin A and beta-carotene supply of women with gemini or short birth intervals: a pilot study" by Schulz C, Engel U, Kreienberg R, Biesalski HK., posted in US National Library of Medicine National Institutes of Health, researchers filed the result that regardless of the high to moderate socio-economic background, 27.6% of participants showed plasma retinol levels below 1.4 micromol/l which can be taken as borderline deficiency. In addition, 46.4% showed retinol intake <66% of RDA and 50.0% did not consume liver at all although liver contributes as a main source for preformed retinol. Despite high total carotenoid intake of 6.9 +/- 3.6 mg/d, 20.7% of mothers showed plasma levels <0.5 micromol/l beta-carotene. Retinol and beta-carotene levels were highly significantly correlated between maternal plasma versus cord blood and colostrum. In addition, significantly lower levels were found in cord blood (31.2 +/- 13.0% (retinol), 4.1 +/- 1.4% (beta-carotene) compared with maternal plasma and concluded that Despite the fact that vitamin A and beta-carotene rich food is generally available, risk groups for low vitamin A supply exist in the western world.