I have read it takes about 100,000 IU (60mg) a day before that side effect starts to occur. Supposedly it is a reversible side effect, but does anyone know if there is a more definite answer or is the 100k IU a good rule of thumb?
Neither of which answers the question.
The amount depends on the age and complexion. Carotenemia is very common in the second half year of life with typical dietary habits. Many baby foods are mostly carrots, sweet potato, or squash, even those that are called “chicken vegetable dinner” and the homogenized nature of baby foods makes the carotene more easily absorbed. The thin skin and subcutanenous fat of infancy makes it easily noted as well. This carotenemia of infancy and toddlerhood is not associated with vitamin A toxicity.
It is less common in older children and in adults. A quick search found this case report of a 74 year old white male with carotenemia on a 20,000 IU beta carotene supplement so I would say the 100,000 cut-off is not a reliable one. His Vitamin A level was normal and his skin color returned to normal within two weeks of stopping his beta carotene supplement.
The first gives at least as much of an answer as you did.
Google the RDA and multiply by between 10 and 30. (I am sure you are right that it varies from person to person, hence the range.)
About 20 years ago, I ate a bag or two of carrots a day to try to turn orange. (This was due to a disagreement with a co-worker who didn’t believe people could turn orange from ODing on carotene.) After about a week, I gave up, because I wasn’t orange, and all those carrots were giving me the runs.
I think you’d need 10 large carrots a day minimum for months to get yellow skin.
You didn’t try hard enough. I’ve seen pictures of people who have done it. It takes about a month to really be noticeable. In all honesty, though, the effect isn’t that great. You eat a buttload of carrots and even then your skin only turns slightly orange-ish.