This has been discussed a lot.. check out the multiple threads via the search function (I'm commenting on it as I've typed these answers a lot..)
It works fine for yellows, some oranges, and some green (because of beta carotene) but doesn't help with reds, some oranges or blues. If you read through the multiple threads it has be explained why a few times...
Astaxanthin (the main carotenoid in Naturerose) colors up reds as well as other colors (but not blue) unlike paprika...
Ed