The 0.85g mentioned in the instruction refers to the weight of the whole vitamin chewable tablet. It not only contains vitamin C, generally speaking, vitamin C only accounts for about a quarter. In fact, there is no need to take two tablets a day. One tablet a day is enough, because you don't have to take vitamin supplements every day. Eat some fruits (oranges and the like) containing some vitamin C every day.

It is best to take vitamin C every other month. Stop taking it for a month and take it again next month. I hope it helps you.