According to Mayo Clinic, consuming too much vitamin C is unlikely to be harmful or to cause an overdose. Too much vitamin C may, however, result in undesirable symptoms, such as diarrhea, nausea, vomiting, heartburn, abdominal bloating, cramps, headache, insomnia and kidney stones.
Mayo Clinic explains that the recommended intake of vitamin C for adults is between 65 and 90 milligrams per day with a limit of 2,000 milligrams. Most people meet the recommended amount if they consume 1 cup, or 165 grams, of chopped red pepper, broccoli or strawberries. Extra vitamin C that has been consumed is removed via the urinary tract.