Vitamin A

Comments Off on Vitamin A

Introduction:

Vitamin A isn’t a nootropic exactly… but it is a very important nutrient for eyesight… go figure. Vitamin A(or A Retinol, retinal, and four carotenoids such as beta carotene) is a nutrient that is needed by the eye’s retina and is converted to the light-absorbing substance retinal. This is required for both dark vision and full spectrum vision. Vitamin A also functionsas an irreversibly oxidized form of retinol known as retinoic acid, which is an important hormone-like growth factor for epithelial and other cells.

Is Vitamin A dangerous?

15,000 to 25,000 IU of vitamin A daily for adults (2,000 IU or more for children) may cause liver damage, headache, vomiting, abnormal vision, constipation, hair loss, loss of appetite, low-grade fever, bone pain, sleep disorders, and dry skin and mucous membranes. It is important never to megadose vitamins and to spread out your vitamin consumption throughout the day by maintaining a healthy diet.

So what is the recommended dosage?

The current RDA for adult males is 5,000 IU, 4,000 IU for females and 2,500 IU for children. I strongly recommend not taking multivitamins and instead consuming your RDA values by eating a healthy and well balanced diet.

Which foods are rich in Vitamin A?

Carrot juice, canned, ½ cup: 22,567IU
Cheese, cheddar, 1 ounce: 284IU
Egg, hard-boiled, 1 large: 260IU
Kale, cooked, boiled, ½ cup: 8,854IU
Sweet potatoes, baked in skin, 1 medium: 21,909IU
Chicken liver cooked, 3 ounces: 11,329IU
Liver, beef, cooked, 3 ounces: 22,175IU

Several less rich sources include:

Lettuce, apricots, mango, peas, oatmeal, broccoli, watermelon, tomatoes and many more.