The metaphor on the use of children, in the video, may come of more as intended by the producers. Aside from children being the future of the world, they are still pure, "innocent" and "uncorrupted" by "maturity", society and other factors such as education and religion.
There are essentially no adults in the music video. Sarah Brightman represents nature as whole (mother nature?).
Of course, by now you know I may also be referring to doctors and nutritionists as well. The wrong or incomplete information will prevent you from getting your goals DONE.
The first video is the actual TVC.
The official music video follows. Sarah Brightman looks a little scary though.