I think I started out with 7g after reading Linus Pauling's book, and went up 1g/day from there.
My sinuses cleared up about a month after the 20g/day of C, but then I'm not sure if it was the C, the oil pulling, or the combination of both.
Anyway, Pauling says that everyone's body's need for C is different. I have a feeling that my digestive tract/sinuses were so alkaline that it took 20g of ascorbic acid to begin to set me normal again.