Facts About Vitamin A DeficiencyVitamin A Deficiency: Not Good
A deficiency in vitamin A generally isn't present in developed countries except for rare cases, especially since most of those individuals are eating enough fats and, hopefully, enough fruits and vegetables. Its more common in less-developed countries where higher-fat foods are scarce. If you recall some of the functions and other facts about vitamin A listed here, you may be able to guess some of the detrimental effects of having a deficiency of vitamin A... Night Blindness Vitamin A is especially important for the visual cycle of the rods in your cornea, which are mostly used in the relative absence of light (at night!). This is the earliest sign of a vitamin A deficiency. When untreated, night blindness can be irreversible, possibly leading to a condition called xeropthalmia. This essentially dries up the eyes, forming scar tissue in the cornea that ultimately results in blindness. Xeropthalmia is mostly seen in children of developing countries where dietary fat intake is very low. Without fat in the diet, its impossible to absorb any form of vitamin A! Growth and Development A child deficient in vitamin A may show signs of growth abnormalities not related to any genetic defect like Achondroplasia or other dwarfing diseases. This is because retinoic acid, a byproduct of vitamin A metabolism, is responsible for the activation of genes that promote growth and differentiation of body tissues. Dariers Disease (Acne) and Psoriasis Vitamin A deficiency can also result in Acne and Psoriasis (chronic itching and flaking of the skin). These conditions are usually caused be a deficiency or problem in the production of keratin. Since retinoic acid effectively helps produce new epithelial linings and promotes the synthesis of keratin, retinoic acid is often used as a treatment for such disorders. Some topical treatments (in the form of a cream that you would rub into your skin) are used to treat acne and normal aging. The main drug used for this purpose is Tretinoin which is simply a solution of trans-retinoic acid. This drug is pretty potent and toxic in large amounts, which is why you cant use it all over your body (its only a topical solution!). The usage of cis-retinoic acid has a completely different purpose... A more potent, oral drug called isotretinoin (a.k.a. Accutane), a solution of cis retinoic acid), is used when conventional acne therapies are ineffective. Immune System Vitamin A also plays a role in immune infection. A deficiency may also cause an increase in bacterial and viral infections! Return from Vitamin A Deficiency to the Nutrition Guide Return from Vitamin A Deficiency to the Smart Strength Training Homepage
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