Vitamin A (also referred to under the name Retinol) has been called the "miracle vitamin" because of its positive impact on immunity and growth. Beauty-conscious women have been known to favour this vitamin because it is believed to slow the ageing process and improve overall skin condition.
Health benefits of Vitamin A
Benefits of Vitamin A include:
- antioxidant properties - helps to protect our cells from damage.
- strengthening immunity against infections
- improves vision.
- promotes formation of strong bones.
- guards us against bacterial, viral and parasitic infections.
- protects against heart disease and stroke, and lowers cholesterol levels.
- can improve skin conditions such as acne or psoriasis.
- its role as a well-known wrinkle eliminator, Vitamin A reduces fine lines and helps fade age spots.
- may help children with respiratory problems.
- it is believed to help patients of glaucoma and measles.
There are 2 natural forms of Vitamin A
Vitamin A is fat-soluble and is available naturally in two forms:
- Preformed vitamin A is known as retinol, is found in highest concentrations in liver, dairy products, eggs and fish oils.
- The second form is beta-carotene, an orange-yellow to red pigment that the body converts to vitamin A when required. Beta-carotene is present in brightly coloured fruits and vegetables - the brighter the fruit, the more beta-carotene it contains. Beta-carotene is found in leafy green vegetables and fruits like apricots, broccoli, tomatoes, carrots and spinach.
The Journal of Nutrition has recently published a study claiming lipid-rich avocado and beta-carotene rich foods improved bioavailability of the carotenoids from these foods and covert them into an active form of vitamin A.
Previous scientific studies back up findings
It is already widely known from previous studies that the absorption of vitamin A is enhanced with co-consumption of lipids. Avocados contain about 17% lipid.
Previous studies also show that consuming unsaturated fats also enhances activity of the enzyme that converts inactive pro-vitamin A carotenes to vitamin A thereby suggesting that consuming avocados with a pro-vitamin A rich food could enhance conversion.
Eating avocado found to increase vitamin absorption by up to 1200%
The study recruited two separate sets of 12 healthy men and women for two randomised studies. The first study investigated whether fresh avocado when eaten with high beta-carotene tomato sauce would promote the absorption of pro-vitamin A carotenoids and their conversion to an active form of Vitamin A.
The second study investigated the same outcome but replaced the high beta-carotene tomato sauce with raw carrots. Both groups were served their test meals at breakfast - with or without 150g of fresh avocado.
Researches found from the first study that the addition of avocado regardless of the presence of tomato sauce more than doubled the absorption of beta carotene and more than quadrupled the conversion of pro-vitamin A to vitamin A.
The second study concluded that compared to a raw carrot meal without avocado, the addition of avocado significantly increased beta carotene more than 6 fold, more than quadrupled alpha-carotene absorption and increased the conversion of pro-vitamin A to vitamin A by more than 12 times.
How much vitamin A do I need?
The amount of vitamin A adults need is recommended to be:
- Men: 700mcg a day
- Women 600mcg a day
Most people should be able to get all the vitamin A you need from their daily diet. If you consume excess vitamin A your body stores it for future use which, this means you do not need it every day.
Excess consumption may cause harm
While vitamin A is considered safe, excess consumption of vitamin A can be toxic and harmful to the body therefore care should be taken to adhere to the recommended daily allowance if you take this in supplement form.