If you eat more carrots, it will NOT improve your vision in any way; despite the abundant myths, this is a fact.
Why do people say it will ? Because carrots contain vitamin A, and because vitamin A is required for vision, people quite reasonably conclude that eating carrots means better vision. But this is one of the long-standing myths that needs de-bunking. So here goes:
The retina is the light-sensitive layer (in the back of the eye) that detects the light and sends the image back to the brain so you can "see". Detection of the image requires production of pigments within the retina, which are made from Retinol (Vitamin A). Vitamin A is made in your liver from Beta carotene which is found in vegetables, especially kale, cabbage, broccoli, spinach, sweet potatoes, carrots. Vitamin A is also of course available already formed in animal products especially, of course, the liver (see above); and it is one of the fat-soluble vitamins so it is also found in oily fish, whole milk, butter and cheese.
But vision requires only a small amount of Vitamin A each day, and our livers store vast amounts of the stuff - so unless you have a very deficient diet for years, such as is very occasionally seen in severe alcoholics, you will have plenty of Vitamin A on board with no risk of Vitamin A related vision deficit. Extra vitamin A in the diet is no advantage to vision.
That said, beta carotene is one of the anti-oxidant substances that protect all of our body cells against the oxidative stresses of daily life. So it's a good addition to our diet for general health reasons.
In developing countries the situation is very different - prolonged nutritionally deficient diets there cause many health problems which, for Vitamin A deficiency include:
Impaired vision in dim light (= "night-blindness")
Dry eyes; can be so severe that the cornea (the clear window on the front of the eye) becomes opaque
Increased susceptibility to skin damage from sun
In children: reduced growth, restricted bone development
Increased susceptibility to infection
In developing countries, a carrot a day would be a fantastic improvement to their diet.
In developed countries, a carrot a day would be general good dietary advice, but not for reason of vision.
Too many carrots (more than about one large carrot per day) causes carotenaemia - not a big health risk, but it makes your skin yellow !
Why do people say it will ? Because carrots contain vitamin A, and because vitamin A is required for vision, people quite reasonably conclude that eating carrots means better vision. But this is one of the long-standing myths that needs de-bunking. So here goes:
The retina is the light-sensitive layer (in the back of the eye) that detects the light and sends the image back to the brain so you can "see". Detection of the image requires production of pigments within the retina, which are made from Retinol (Vitamin A). Vitamin A is made in your liver from Beta carotene which is found in vegetables, especially kale, cabbage, broccoli, spinach, sweet potatoes, carrots. Vitamin A is also of course available already formed in animal products especially, of course, the liver (see above); and it is one of the fat-soluble vitamins so it is also found in oily fish, whole milk, butter and cheese.
But vision requires only a small amount of Vitamin A each day, and our livers store vast amounts of the stuff - so unless you have a very deficient diet for years, such as is very occasionally seen in severe alcoholics, you will have plenty of Vitamin A on board with no risk of Vitamin A related vision deficit. Extra vitamin A in the diet is no advantage to vision.
That said, beta carotene is one of the anti-oxidant substances that protect all of our body cells against the oxidative stresses of daily life. So it's a good addition to our diet for general health reasons.
In developing countries the situation is very different - prolonged nutritionally deficient diets there cause many health problems which, for Vitamin A deficiency include:
Impaired vision in dim light (= "night-blindness")
Dry eyes; can be so severe that the cornea (the clear window on the front of the eye) becomes opaque
Increased susceptibility to skin damage from sun
In children: reduced growth, restricted bone development
Increased susceptibility to infection
In developing countries, a carrot a day would be a fantastic improvement to their diet.
In developed countries, a carrot a day would be general good dietary advice, but not for reason of vision.
Too many carrots (more than about one large carrot per day) causes carotenaemia - not a big health risk, but it makes your skin yellow !
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