UNICEF has said a program that gives children two large doses a year of vitamin A could all but eliminate VAD, although more frequent, smaller doses would be better.
For an example of this, consider the case of vitamin A deficiency (VAD).
But just as I would trust my doctor or nutritionist to create a custom vitamin formula for me based on all my medical records and health conditions, I would be a million times more comfortable letting the system do it based on every bite I swallow, every bit of my genetic code, and every byte of data about the billion people to which it has access.
The brown-eyed redheads have slower reflexes and should consider getting more Vitamin X (or whatever it is).
Rice doesn't naturally have vitamin A. Enter transgenics.
It has more than twenty times the vitamin A of the original, and efforts are now under way to add vitamin E, iron, and zinc, and to improve protein quality through genetic modification.