"Too much vitamin C can cause diarrhea, stomach ache, heartburn, esophagitis and even kidney stones," Nadeau adds. The good news, Nadeau notes, is that taking too much usually only happens when ...

How much vitamin C per day? The Recommended Dietary Allowance (RDA) for vitamin C depends on a handful of factors, including age and sex (for adults): 0 to 6 months: 40 mg 7 to 12 months: 50 mg 1 ...