Vitamin A is commonly known as the vitamin needed for good eyesight. A vitamin A deficiency primarily causes impaired vision and increases susceptibility to infectious diseases.
The visual cycle
When we look at objects, light is reflected from the object and enters the eye, striking a tissue located in the back of the eye. This tissue is known as the retina. When light strikes the retina, retinol is converted to retinol, which is then shuttled to rods – the cells that help you to see in the dark. In rod cells, the retina binds to a protein called opsin. As a result, opsin changes shape and causes nerve impulses to be generated. These nerve impulses then carry messages to the brain regarding the objects in our visual field. Retinal is then converted back to retinol, ending the visual cycle.
A hallmark of vitamin A deficiency is night blindness – an impaired ability to see in low-light conditions. This is because, with the reduced availability of retinol, the nerve impulses necessary for our brain to interpret visual information are hindered.
The benefits of Vitamin A are good for your eyes and eyesight in 3 major ways: helps prevent night blindness, prevents cataracts (like Vitamin C), and helps to preserve eyesight. Let’s go over how Vitamin A & beta carotene benefit each one…
For Night Blindness… your retinas are light-sensitive cells that have a large amount of Vitamin A stored in them. And within your retinas, you have a thing called rods and cones. Rods and cones allow you to see black & white and colors, respectively. The rods are specifically used for night vision.
Without getting too scientific, rods use a combination of a special protein called opsin and a specific form of Vitamin A (called retinal) in order to function properly. Without Vitamin A portion… the rods would not work properly and you won’t be able to see that well in dark or in dim lighting. This is especially true as you get older.
The next one is about Cataracts. Cataracts form when the lens of the eye becomes cloudy… making it very difficult to see. Cataracts used to be one of the leading causes of blindness.
But a better way to prevent this from happening (and avoid the surgery to fix it) is to have a diet rich in carotenoids… especially beta carotene.
The antioxidant power of beta-carotene wipes out the free radicals before they damage the lens.
Vitamin C is also helpful in preventing cataracts. So combining these 2 will definitely help to prevent cataracts.
And lastly, it helps to preserve your eyesight. As you grow older there is a thing called Age-Related Macular Degeneration (AMD) which causes some vision loss. AMD is one of the leading causes of blindness in people older than 65. And about 31% of Americans 75 and older have it.
One study suggests that eating just one serving of a food high in Vitamin A or beta carotene can reduce the chances of AMD by almost half! A few other carotenoids (i.e. Lutein and zeaxanthin) are also helpful in preserving your eyesight as you get older.
So if you like your eyes and want to keep your eyesight healthy for a long time… it’s best to take Multivitamin for men. It includes Vitamin A and beta carotene and all you need.