At recommended doses, vitamin C supplements are safe. However, they can cause upset stomach, heartburn, cramps, and headaches in some people. High doses of vitamin C can cause more intense symptoms, such as kidney stones and severe diarrhea.

Is ascorbic acid safe to eat?

The U.S. Food and Drug Administration (FDA) states that ascorbic acid is a generally recognized as safe (GRAS) substance for use as a chemical preservative in foods and as a nutrient or dietary supplement.

What happens if you eat ascorbic acid?

The most common digestive symptoms of excessive vitamin C intake are diarrhea and nausea. Excessive intake has also been reported to lead to acid reflux, although this is not supported by evidence ( 1 , 3 , 4 , 5 ).