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Vitamin A
Retinol, the animal form of vitamin A, is a yellow fat-soluble, antioxidant vitamin important in vision and bone growth. It belongs to the family of chemical compounds known as retinoids. Retinol is ingested in a precursor form; animal sources (milk and eggs) contain retinyl esters, whereas plants (carrots, spinach) contain pro-vitamin A carotenoids. Hydrolysis of retinyl esters results in retinol while pro-vitamin A carotenoids can be cleaved to produce retinal. Vitamin A is required in the production of rhodopsin, the visual pigment used in low light levels. This is why eating foods rich in vitamin A is said to allow you to see in the dark.
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Health & Medicine News
May 15, 2026
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May 14, 2026 Scientists analyzing the genomes of thousands of people across Japan discovered evidence for a previously overlooked third ancestral group, challenging the long-accepted “dual origins” theory. The newly identified ancestry appears linked to the ...
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May 13, 2026 The little pauses, “ums,” and moments when you struggle to find the right word may reveal far more about your brain than anyone realized. Researchers discovered that everyday speech patterns are ...
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May 12, 2026 Scientists at the University of Maryland, Baltimore County, have uncovered a crucial trick used by enteroviruses—the group behind diseases like polio, myocarditis, encephalitis, and even the common ...
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May 12, 2026 Scientists at McGill University have uncovered a hidden molecular “switch” that turns on a powerful calorie-burning system in brown fat — the body’s heat-generating fat linked to metabolism ...
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