Skip to main content

Importance of vitamin A to vision

AS we grow older, our eye lens loses its elastic nature and becomes relatively a solid mass, a condition which eye doctors often referred to as presbyopia.

When this happens, the eyes are more or less permanently focused and are no longer able to accommodate both near and far vision. This is one of the reasons an older person often needs to wear eye glasses with bifocal lenses, with the lower portion of the glasses being of stronger power for close vision, while the upper portion allows him to see more freely at a distance.

The iris is a beautiful circular curtain like structure lying in front of the lens of the eyes. Orientals (Asians) generally have brown eyes, but the western people may have brown, blue, green, grey, or black, depending on their family background.

The iris, according to eye doctors, has a very important function, for it controls the amount of light that enters the eyes. The central black spot, or what is commonly called pupils, opens up wide in darkness, but becomes narrowed and small in bright light. This widening and narrowing is done by Iris which acts like the diaphragm on the camera, allowing just the right amount of light to enter the eye, and at the same time, giving a greater depth of focus when the opening is small. Thus, the size of the pupil is automatically adjusted according to the amount of light and sharpness of vision.

•Colour vision—In the retina, or screen, at the back of the eye, ophthalmologist explained that there are two types of nerve cells—the rods and cones, and both are said to be sensitive to light, with the rods being especially important in a dim light, while the cones react to colour and fine detail. You are using your cone cells as you read the words in this article. If you tried to see this whole page at a glance, in doing so, you are using the rod cells which are widely spread. Throughout the retina. But in reading the fine print, expert says you have to focus down on a small central spot, or fouea, on the retina where the cones are very numerous. The retina is well supplied with an important chemical substance called rhodospin, or “visual purple.” light falling on the retina brings about certain chemical changes in the rhodopsin and other substances present in the rods and cones. All these changes occur very rapidly, but large quantities of vitamin A are needed to make this happen. That is why we need to take good amount of vitamin A, yeast and other vision—enhancing medication supplements, fruits and vegetables as may be prescribed by our eye doctor. Some people even say they eat carrots a lot in order to get good amount of vitamin A and carotene, needed for good vision.

If there is any marked deficiency of vitamin A, especially from childhood, night blindness may occur, and that is why parents are advised to give Vitamin A drops to their infants in order to prevent eye trouble and to enhance good vision. Vitamin A can also be got from certain fruits and vegetables.

The importance of vitamin A in our diet cannot be under estimated. For example, vitamin A is called the “beauty vitamin” as it helps to keep the skin smooth and soft apart from boosting good, bright vision.

Vitamin A is also needed for the mucous membranes lining the nose, throat, and bronchial tubes, as well as the entire digestive tract, the bladder, kidneys, and pelvic organs. This “beauty vitamin” also aids in the normal growth of bones and teeth, particularly in children and young people.

If one take it as a duty to regularly eat green and yellow vegetables and fruits, then one need not worry about getting too much or too little of vitamin A. This is because vitamin A is formed from a chemical substance known as carotene, which is present in all green leafy vegetables, especially amaranth leaves, carrots, sweet potatoes, squash, pumpkins, apricots, payaya (pawpaw), mangoes, avocados (butterfruit), melons and nearly all yellow fruits. Any diet containing an abundance of fresh fruits and vegetables will also be rich in vitamin A.

This vitamin helps to fight infections diseases and keeps our eyes bright and also helps us to see in a dim light. Remember, without vitamin A, our vision would soon be impaired, smaller than the other.

#Copied

#April


Comments

Post a Comment

Popular posts from this blog

PRAYER FOR FORGIVENESS. We have ridiculed the absolute truth of God's word and called it 'pluralism'. We have worshipped other gods and said 'give to Caesar what belongs to Caesar'. We have endorsed pervertion and called it 'alternative life style'. We have exploited the poor and called it 'lottery'. We have rewarded laziness and called it 'welfare'. We have committed adultery and called it 'playing around'. We have committed fornication and called it 'having fun'. We have killed unborn children and called it 'choice'. We neglected to discipline our children and called it 'building self esteem'. We have abused power and called it 'politics'. We have converted our neighbour's property and called it 'ambition'. We have polluted the air with profanity and pornography and called it 'freedom of expression'. We have ...
Post a Comment
Read more

#NextGeneration Stories

Cherokee Legend Do you know the legend of the Cherokee Indian youth's rite of Passage? His father takes him into the forest, blindfolds him and leaves him alone.  He is required to sit on a stump the whole night and not remove the blindfold until the rays of the morning sun shine through it. He cannot cry out for help from anyone.  Once he survives the night, he is a MAN. He cannot tell the other boys of this experience, because each lad must come into manhood on his own. The boy is naturally terrified. He can hear all kinds of noises. Wild beasts must surely be all around him. Maybe even some humans might do him harm. The wind blew the grass and earth, and shook his stump, but he sat stoically, never removing the blindfold. It would be the only way he could become a man! Finally, after a horrific night the sun appeared and he removed his blindfold. It was then that he discovered his father sitting on the stump next to him.    He had been at watch the entire night, p...
Post a Comment
Read more

Why Do You Smoke?

6 personalized approaches to quitting forever.  Everyone smokes—and quits—for different reasons, and the key to getting smoke-free for life is to find out why you are smoking and then change those behaviors. If you are a Recreational or Social Smoker, you may feel that your limited smoking poses no serious medical harm to yourself or others. You may, however, ignore warning signs that your occasional smoking is progressing into addiction, especially during periods of stress or increased alcohol use. A periodic review of these warning signs may help motivate you to consider becoming smoke-free. The Scared-to-Quit Smoker has no end of reasons (excuses) to put off going smoke-free to some future date. Sometimes it helps to focus on just quitting for one day. If you can quit for a day, you can quit every day. This realization can be a great confidence builder, and helps to decrease your fears about not smoking “ever again.” Forever is too big a word for many addicts; thus the old adage...
Post a Comment
Read more