Vitamin A

Vitaman A is a fat-soluble vitamin that can be divided into two groups, carotenoids and retinoids. Carotenoids are found in plants and are called provitamins because they are stored in the liver and converted to vitamins as needed. Of the many carotenoids there are only about six included in a typical diet including alpha-carotene, beta-carotene, cryptoxanthin, lycopene, lutein and zeaxanthin. Retinoids come from animals and are called active vitamin A because they are already in a form that is usable by the body.

Functions of Vitamin A may include: required for vision, needed for growth and support of the skin, assists in immune function, strengthens bones during development, decreases bad cholesterol, helps prevent prostate cancer, lowers blood pressure.

Symptoms of Vitamin A deficiency may include: dry eyes, fatigue, hypothyroidism, increased susceptibility to infections, nigh blindness, poor tooth sand bone function, poor wound healing and rough skin.

Causes of Vitamin A deficiency may include: antibiotics, diabetes, cholestorol-lowering medications, laxatives and malnutrition.