Vitamin A deficiency

Vitamin A is a fat-soluble organic compound necessary for vision and health of epithelial tissue. It is converted into dietary beta carotene and three other carotenoids in the body. 80 - 90% of vitamin A is stored in the liver

Vitamin A is also known as retinol. Natural and synthetic compounds from retinol are known as retinoids.

New synthetic compounds acting through the retinoid pathway include tazarotene, bexarotene, and adapalene.

The normal range of vitamin A / retinol is 28-86 μg / dL. Vitamin A deficiency is defined as serum retinol levels below 28 μg / dL. Vitamin A deficiency may cause blindness, skin disease, growth disorder in children

Vitamin A deficiency is prevalent in Africa and Southeast Asia, and it is estimated that 250 million infants suffer from this deficiency due to the lack of carotenoids in their diet. Severe infection, especially measles, may worsen the symptoms

Vitamin A deficiency also occurs in adults with gastrointestinal disorders that interfere with vitamin A absorption. These diseases are as follows.

Vitamin A deficiency can also be identified by keratinization of skin and mucous membranes.

Diagnosis of vitamin A deficiency is usually clinical. The history of dark adaptation disorder highly suggests Vitamin A deficiency, but it can also occur in the therapeutic use of retinoids (eg isotretinoin for acne treatment). The findings of dry eye and dry skin suggest vitamin A deficiency, but may be due to other causes

Serum vitamin A / retinol is useful if its level is less than 28 μg / dL, but if the deficiency is mild, results may be normal. Low circulating levels of vitamin A do not decrease until the supply of vitamin A from the liver is depleted, so low retinol levels indicate late stages of the disease

Vitamin A deficiency is treated with vitamin A palmitate oil at an oral dose of 60,000 IU for 2 days, then it is administered orally 4,500 IU per day.

Fruits rich in beta carotene such as apricot and peach, vegetables with rich colors such as carrots, pumpkin, sweet potato

Supplements of vitamins and minerals are important in preventing symptoms and preventing disease. Most diseases caused by vitamin deficiency such as scurvy (vitamin C deficiency), night blindness (vitamin A deficiency), and beriberi (thiamine deficiency) occur mainly in countries of the third world, and most exist in the United States No. However, because vitamins and mineral deficiencies can occur in certain special populations in the United States, dietary supplements are necessary. For example,

Vitamin deficiency is a form of malnutrition, especially vitamin deficiency which is a health problem in the United States. According to a study published in Journal of Internal Medicine in 2009, more than 75% of Americans lack Vitamin D. Vitamin D is a fat-soluble vitamin obtained by eating oily fish such as reinforced milk and salmon. Vitamin D deficiency is associated with increased risk of bone diseases such as osteoporosis, autoimmune disease, certain cancers, obesity

One billion people worldwide are estimated to suffer from vitamin D deficiency or deficiency. The group at high risk of vitamin D deficiency includes people far away from the equator, those with medical conditions (obesity, liver disease, celiac disease, kidney disease etc.), the elderly, and the darker skin . According to the National Health Nutrition Survey, people with darker skin have a lower level of vitamin D, including more than 15,000 adults. People with dark skin contain high levels of melanin. This can impair the absorption of vitamin D produced when the skin is exposed to ultraviolet light from natural sunlight.