Well I don't drink bottled carrot juice because it lacks enzymes. The vitamin content gets altered as the bottled stuff gets flash pastuerized. It all depends on her level of health - if she finds it a good replacement for diet soda of coffee then it's good. I would not waste money on it for health reasons. Get her distilled water and a lemon squeezer. 1st thing in the morning juice 1/2 a lemon into the water and drink it down - you can add cayenne if she likes a kick (even mere alkaline)..You can also do this in the evening.
Ideally the lest sweet it is and the less processed and the younger it is. The better it is for you
PS MH I finished "the book "school of self- apploed prevention" it was a good read though I'm curious on your take on Sick and Tired by dr young.