It is still a matter of context.No problem. Too much vitamin C can be hard on the kidneys.
A failing kidney, perhaps.
With normal kidneys, excess Vitamin C leads to it being excreted through the kidneys, in the form of urine. Just as taking excess electrolytes would do to you, except that with Vitamin C, it has the effect of cleaning the kidney, bladder, urinary tract, of bacteria.
But what is too much? The amount of Vitamin C needed varies by condition. A healthy person would need just 1 gram a day. A very, very sick person would need as much as 300 grams a day, and would need IV infusion. Dr. Cathcart has a way of determining a person's daily vitamin C requirements using a Vitamin C Flush test. Conventional medicine, however, is not willing to consider vitamin C supplementation more than 1 gram a day. Anything above that is considered too much.