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Recessive genes that make a carrot orange

phys.org

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Re: Recessive genes that make a carrot orange

#4
Because the article mentions “health benefits” of beta carotene, I feel it’s important to bring up that carotenes have an awful and highly variable absorption rate in humans, with beta carotene generally being considered the best. The specifics will also heavily depend on genetics and the particular food eaten. It should be noted that other animals differ significantly in their absorption rates.

Carotenes once absorbed then go on to have an also awful and highly variable conversion rate to retinol.

While I’m not sure if it’s the best, this paper seems to mirror the concerns with carotenes I cane across when I last explored the subject, so I’ll throw this out as a reference: https://www.sciencedirect.com/science/article/pii/S000291652...

“The absorption of β-carotene from plant sources ranges from 5% to 65% in humans. Vitamin A equivalency ratios for β-carotene to vitamin A from plant sources range from 3.8:1 to 28:1, by weight. Vitamin A equivalency ratios for β-carotene from biofortified Golden Rice or biofortified maize are 3.8:1 and 6.5:1, respectively, and are lower than ratios for vegetables that have more complex food matrices (10:1 to 28:1). The vitamin A equivalency of β-carotene is likely to be context-specific and dependent on specific food- and diet-related factors and the health, nutritional, and genetic characteristics of human populations.”

As such, any time you see beta carotene listed as a substitute for “vitamin A”, you are likely being mislead, as you have to both win the genetic lottery and obtain it from specific foods for it to be even partially viable as a substitute.

Re: Recessive genes that make a carrot orange

#5

Because the article mentions “health benefits” of beta carotene, I feel it’s important to bring up that carotenes have an awful and highly variable absorption rate in humans, with beta carotene generally being considered the best. The specifics will also heavily depend on genetics and the particular food eaten. It should be noted that other animals differ significantly in their absorption rates. Carotenes once absorb…

It's my understanding that the conversion of beta carotene to vitamin A is variable because it's inhibited if your body has enough vitamin A. Too much vitamin A is toxic; I believe beta carotene is much less so.

Re: Recessive genes that make a carrot orange

#7
I was going to post that Orange carrots were deliberately created (or atleast grown in quantity and sold) by farmers to celebrate William of Orange and Dutch independence, but this appears not to be true (or atleast unproven)

https://www.livescience.com/why-are-carrots-orange.html

My local market sells a bag of mixed coloured carrots - white, purple, yellow, and orange - and the orange is by far the sweetest and tastiest, some other colours are fairly inedible raw.