Hi all! Please don't "megadose" vitamin C & D for Covid protection. It can cause kidney stones.
-your friendly local Urologist.

To be more specific:
Excess vit C = hyperoxaluria--> stones
Excess vit D= hypercalciuria--> stones
NEITHER: COVID prevention.

There are infinitely more ways to expound on renal physiology but that's the 5 second lesson.

I'm getting alot of questions about what defines a "megadose." I am generally referring to products that provide vitamins greatly in excess of the RDA, generally for flashy marketing claims.

Most people who consume fruits & vegetables do not need additional vitamin C (vit C deficiency is Scurvy). If you want to take a vit C supplement, 500mg is a great dose. You do not need to take more than 1,000mg. Extra vit C gets converted to oxalate in the urine.

Vit D is more complicated. There are people with true vit D deficiency who need to take high doses. If you think you might have vit D deficiency talk to your doctor and get tested. Do not medicate for low D without knowing. That can be very dangerous.

For everyone without vitamin D deficiency, who just wants to prevent vit D deficiency, USUALLY 2,000 IU or less is sufficient. Vitamin D toxicity messes with your calcium regulation and causes you to pour extra calcium into urine, even if you eat normal amounts of calcium.

Ok I have a bunch of work I have to do today but I will post a more data- dense thred in the future. Thanks for joining this discussion!

One last comment to ppl mentioning that "vit C is water soluble so it shouldn't be a problem." It IS a problem.
1) if you take too much vit C your body just pees it out
2) because you pees it out you are not getting any health BENEFIT
3) in your pee it becomes oxalate (cont)

4) oxalate in the urine is a major contributor to stones. Calcium Oxalate stones are the most common type of stones & are caused by too much oxalate, not too much calcium
5) I have seen folks w stones on "low oxalate diet" taking vit C supplements, negating their good effort!