@Mj442k ...the issue is whether chameleons can convert prOformed sources (beta carotene sources from veggie, greens) OR not. If they can convert it then gutloading the insects with veggies and greens so the chameleon will be able to use those undigested veggies and greens to co nvert into prEformed will help. If the chameleons can't convert it then the insects will still have the normal amount of prEformed vitamin A they would have without gutloading which some people are saying isn't as much as a chameleon would get from its wild diet. So they're saying we need to provide the chameleon with some prEformed vitamin A to make up for what they will lackmin their captive diet.
There's one more hitch in all of this...vitamin A from prEformed sources has to balance with the D3 in the chameleon because it's antagonistic to the D3. If there's an imbalance then the chameleon can end up with MBD.
And also...if there is too much prEformed vitamin A and too much D3 from supplements that might cause organ damage.
Not sure all of that is directly involved in the eye issues.