Justin asked, “Is there a specific brand of vitamin A that you prescribe?”
Chris: Yes, cod liver oil almost nine times out of 10 is the best source of vitamin A. If for some reason they can’t take that, then just retinol would be fine. It doesn’t have a lot of beta-carotene in it. For maintenance, it kind of depends on how much vitamin D and environmental K2 they’re getting because vitamin D and K2 protect against the possible toxicity of higher doses of vitamin A, and I’m not really worried about vitamin A toxicity when someone has sufficient vitamin D and vitamin K2. It also depends on their background intake of vitamin A and retinol.
I mean, most people, I would assume that they don’t need to take additional vitamin A, especially if they’re taking cod liver oil and/or they’re eating organ meats. They generally will not have to take additional vitamin A. If they’re not eating organ meats and they’re not willing to eat organ meats, then taking additional vitamin A can be helpful, so maybe depending again on their background intake, like, if you compare it to cod liver oil, a teaspoon of cod liver oil, depending on the brand, might have something like 4,000 IU of retinol. You might then consider a similar dose of retinol, provided they’re getting enough D and K2.