What is it?
There are two types of vitamin A that are found in the diet.
- Preformed vitamin A is found in animal products such as meat, fish, poultry and dairy foods.
- Pro-vitamin A is found in plant-based foods such as fruits and vegetables. The most common type of pro-vitamin A is beta-carotene.
Vitamin A is also available in dietary supplements, usually in the form of retinyl (retinol) acetate or retinyl palmitate (preformed vitamin A), beta-carotene (provitamin A), or a combination of preformed and provitamin A. Most multi-vitamins contain Vitamin A.
What it does
Vitamin A is necessary for proper vision, resistance to infectious diseases, epithelial cell integrity, bone remodelling and sperm reproduction. Vitamin A deficiency usually results from malnutrition, but can also be due to abnormalities in intestinal absorption of retinol or carotenoids. Deficiency is prevalent in humans, especially children in certain underdeveloped countries.
Vitamin A can be found in liver (beef, pork, chicken, turkey, fish), carrots, broccoli leaves, sweet potatoes, kale, butter, spinach, pumpkin, collard greens, cantaloupe, eggs, apricot, mango and winter squash.
Recommended Dietary Allowance (RDA)
Canada’s RDA can be found here.
Molecular Dosage Range
Your health care provider may recommend a dose that is somewhat higher than the RDAs; sometimes much higher amounts during certain illnesses. Vitamin A is known as the anti-infective vitamin because it maintains healthy mucous in the respiratory system and thus fights off infection and allergic symptoms.