Yes, Vitamin A plays its major role in human beings enhancing good vision. As such, your diet should at least include vitamin A to protect yourself against poor vision and other eye afflictions such as cataracts.
For general eye health, Vitamin A-rich foods are recommended over supplements.
How does Vitamin A help with Eyesight or Vision?
To understand the mechanism around the enhancement of good vision by vitamin A, need to understand the chemistry of the components of Vitamin A as well as the structure of our eye.
Vitamin A is a precursor to the formation of the photo-pigment rhodopsin located in the rods. The formation of rhodopsin is determined by Vitamin A which should be first converted to 11-cis–retinal (2).
Our ability to see is therefore dependent on two main photoreceptors located in the posterior of the eye namely the rods and cones.
Our ability to sight is enhanced by the light that enters into the eye and passes through the lens of the eye and then travels via the posterior segment.
This light must pass through 10 layers of the neural retina to get to the rods and cones which contain the nucleus and the outer segment made of discs consisting of light-absorbing photopigments (1).
When you compare the two photoreceptors, the rods play a significant role for night vision while the cones are useful for day vision.
For the entire mechanism, Vitamin A is one of the fundamentally required precursors for rhodopsin, the pigment in rods.
Therefore, Rhodopsin helps us to see at night, and without vitamin A, Rhodopsin cannot be formed thus night blindness.
Sources of Vitamin A for Vision
Are you wondering where to get the vitamin A components we are talking about? Well, we are here to provide you with the adequate information you need. Good sources of Vitamin A include;
- Fortified low fat spreads
- Milk and yogurt
- Liver and liver products such as pâté
You can also find Vitamin A by including good sources of beta-carotene in your diet since the human being body is capable of converting it into retinol (1).
The primary food sources of beta carotene include yellow, red, and green leafy vegetables such as sweet potatoes, carrots, and spinach.
How much Vitamin A do I need?
If you are an adult aged 19 to 64 years, you required about 700micrograms a day for men and 600 micrograms a day for females.