Home > Nutrition > Vitamin C Side Effects

Vitamin C Side Effects

The Vitamin C side effects may surprise you. The upper limit for adults is around 2000mg (2 g) per day and the side effects of Vitamin C start at doses of more than 2,000mg. The side effects include upset stomach, cramping, and diarrhea.

For the most part those are the most commonly occurring side effects of Vitamin C.

But wait… there are some other Vitamin C side effects that you should be aware of and they include…

  • If you drink too much OJ in order to get your fill of Vitamin C it could stain your teeth yellow (perfect for your first date).
  • If you’re taking high doses of Vitamin C daily for a long time and you suddenly stop… you could have a withdrawal, or rebound, type scurvy. This basically means a mild form of scurvy. To counter this you should slowly decrease your intake on a daily basis for 2-4 weeks.
  • Too much Vitamin C could be mistaken for blood in the stool. This may interfere with lab tests (i.e. testing for colon cancer).
  • Could also interfere when testing for blood sugar. This is especially important for diabetics.
  • Since Iron and Vitamin C affect each other, it may be unsafe for people who cannot regular iron absorption all that well.
  • Excess Vitamin C should be avoided by those with renal impairment, or on chronic dialysis. This is because Vitamin C is a water-soluble vitamin and you get rid of excess Vitamin C by peeing it out (through urine). Those who have renal issues or are on dialysis have an issue with filtering water-soluble substances in the body, including Vitamin C.
  • The verdict is still out on this one: excess Vitamin C should be avoided by those who are susceptible to kidney stones. Studies have shown that people who have a hard time with kidney function should keep their Vitamin C intake in check.

However, there have been studies to disprove this theory and have concluded that Vitamin C may even help to reduce your chances of kidney stones. Check with your doctor before supplementing on Vitamin C if you have either of these conditions.


It’s a good thing you won’t die or anything crazy like that if you take too much vitamin C. It’s a water-soluble vitamin & antioxidant so you’ll basically get rid of any extra Vitamin C through your urine.

That being said the most common side effects to be aware of are upset stomach, cramping and possible diarrhea. Just do yourself a favor and talk with your doctor first to be on the safe side.

Leave a Reply

Your email address will not be published. Required fields are marked *

*