In the first part of ‘The Foundation Series’ vitamin and mineral edition, we focussed on magnesium – my all time favourite mineral! Now, it is my great pleasure to introduce you to Vitamin A, another amazing vitamin required in adequate amounts for optimal health and wellbeing.
Okay, so there are two parts to this story. We have the main character – Vitamin A – but also a very significant off-sider – Beta Carotene. I know its confusing, but keep reading…
What is vitamin A?
Vitamin A is a fat-soluble vitamin that encompasses many different forms. One of these is beta-carotene, which we will cover in a minute. Vitamin A is also commonly know as retinol in which many natural and synthetic compounds are derives such as retinal and retinaldehyde. Don’t worry…you don’t need to remember these names! A fun fact for you though: 80-90% of vitamin A is stored in the liver.
What is beta carotene?
Beta-carotene is the precursor to Vitamin A. It is a carotenoid, meaning it forms part of a group of foods with red, yellow and/or orange fat-soluble pigments which give colour to plants. Beta carotene also acts as an antioxidant with studies showing a preventative role in cardiovascular disease and cancer. It is converted to vitamin A on a needs basis and this occurs in the the digestive tract with the help of bile salts and other fats, vitamin C, zinc and thyroxine. Thus, the ability of beta-carotene to be converted to vitamin A can be dampened in cases of thyroid malfunction as well as other illnesses/disorders such as diabetes, insulin resistance and crohns disease.
Why do we need it?
Vitamin A plays a very important role in growth and repair of body tissues, it helps to maintain healthy skin and eyes as well as form part of the protective linings of the lungs and intestines. Vitamin A is important in thyroid help as is plays a part in the production of thyroxine by the thyroid gland as well as the binding of this thyroxine to its receptors. Vitamin A is important in immunity and reduced susceptibility to infections. It is also important in the formation of bones and teeth, it keeps our eyes strong and healthy and plays a role in healthy sperm production.
Vitamin A helps to mobilise iron from storage sites within the body, hence a deficiency of vitamin A may exacerbate an iron deficiency.
Signs of inadequate Vitamin A include night blindness, impaired immunity, growth retardation in children, dry skin and lips and thickened tongue amongst many others.
Best food sources of Vitamin A (aka retinol).
Retinol is the form of Vitamin A consumed when eating animal sources.
Being a fat soluble vitamin, Vitamin A foods sources need to be consumed with a source of fat for optimal absorption.
Best food sources of beta-carotene.
- Carrots, juiced or whole
- Sweet potato
- Beans and peas
…aka the orange vegetables with some exceptions.
How much do we need?
The RDI for Vitamin A is 900mcg/RE or 3000IU/day.
Vitamin A is very sensitive to light and oxygen, with up to 40% of it being lost in cooking.
Vitamin A requires zinc in adequate amounts to be able to be efficiently mobilised from liver stores.
**I always recommend checking in with your healthcare practitioner and/or nutritionist if you feel like you before purchasing any supplements and/or if you feel like you would benefit from supplemental help. They can also guide you on how best to reach your RDI.
Check out the following editions of ‘The Foundation Series’ for more information.
The Foundation Series – Protein: The 411
The Foundation Series – Protein: Sources
The Foundation Series – Protein: Plant Protein Cheat Sheet
The Foundation Series – Carbohydrates: The 411
The Foundation Series – Fibre: The 411
The Foundation Series – Fat: The 411
The Foundation Series – Magnesium: The 411