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VITAMINS A & D Vitamin A
There are two dietary forms of vitamin A. Preformed vitamin A (retinol) is fat soluble and found in animal products, such as fish liver oils, liver, eggs, butter, cheese and milk. Beta carotene is a water-soluble precursor to vitamin A that is found in plant foods, such as apricots, carrots, spinach, sweet potatoes, pumpkin, dandelion greens, collards, Swiss chard, oat flakes, cantaloupe and other green and yellow fruits and vegetables. Diabetics and those with low thyroid function may have difficulty converting beta carotene into retinal; therefore, they need to get most of their vitamin A from retinol. Beta carotene has antioxidant and cancer-fighting properties above and beyond its ability to provide vitamin A. Supplementary range for retinol: 10,000 to 35,000 IU daily. Supplementary range for beta carotene (if no retinol is taken): 30,000 to 180,000 IU. Supplementary range for beta carotene if taken in addition to retinol: 3,000 to 30,000 IU.
Sources: sunlight, cod liver oil, egg yolks, liver, herring, sardines, salmon, tuna, organ meats. Supplementary range: 400 to 800 IU daily. Copyright © David W. Rowland, 2001
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