Ever been badgered by your parents as a child to eat more carrots?’ It’s good for your eyesight’ they said. This is age-old advice that has been given to children for generations, but is there any scientific truth behind it? In fact, there is. The answer – vitamin A.
But have you ever wondered what this nutrient actually is, why we need it and where we can get it from?
What is vitamin A?
Vitamin A is a group of fat-soluble nutrients- these different forms are found in different types of foods and are broken down in the body in a variety of ways. This process produces different forms of vitamin A that carry out a number of functions, such as retinol which acts as a storage form of the nutrient.
Why we need it
Vitamin A plays several roles in maintaining health- it’s needed for normal reproduction and development, vision and immune function.
The nutrient is needed by the retina in the eye, helping form the molecule that is responsible for absorbing light. This molecule is necessary for low-light and colour vision- so your parents were right!
Vitamin A also supports both male and female reproduction, as well as embryonic development, by maintaining healthy levels of cell growth.
While in the immune system, vitamin A is needed for normal cell regeneration and function- without the nutrient, your body can struggle to fight infections.
Not only that, but vitamin A also has antioxidant properties, which protect cells against the effects of free radicals. Free radicals are naturally produced by cells when breaking down food, but can also occur with exposure to radiation or tobacco smoke. Free radicals may be associated with aging, heart disease and cancer.
How to get enough
The recommended daily dose of vitamin A is 0.9 milligrams for adult men and 0.7 milligrams for adult women. However, we can only get vitamin A from what we eat and drink.
Vitamin A is only found in foods from animals, such as liver, dairy products and fish liver oil.
While orange and yellow-coloured fruits and vegetables, such as carrots, and green leafy vegetables, including spinach and lettuce, are rich in beta-carotene. Beta-carotene is converted into vitamin A by the body.
For most people, a healthy and varied diet is sufficient in fulfilling daily vitamin A needs.
Finding the right balance
Vitamin A deficiency is relatively rare. But if you consume high volumes of alcohol, have conditions like liver disease, cystic fibrosis or coeliac disease, or have recently had gastrointestinal surgery, your body’s ability to absorb vitamin A may be compromised.
Vitamin A deficiency can interfere with your vision, particularly at night, and your immune system’s ability to fight infections. To treat this, doctors usually prescribe vitamin A supplements.
Be warned- excessive vitamin A consumption can be harmful, with symptoms including nausea, vomiting, headaches, muscle and abdominal pain and weakness and drowsiness. Excess vitamin A during pregnancy has also been linked to birth defects.
As such, it’s important to get the balance right.