Final answer:
High doses of vitamin C can lead to gastrointestinal upset, involving symptoms like diarrhea, nausea, and abdominal cramps.
Step-by-step explanation:
Research studies show that consuming high doses of vitamin C can lead to gastrointestinal upset. While vitamin C is essential for health, it is a water-soluble vitamin and excess amounts are excreted; however, taking large quantities can still cause symptoms such as diarrhea, nausea, and abdominal cramps. Other micronutrients can also be toxic at high doses, so adhering to the Tolerable Upper Intake Levels (UL) is crucial to prevent toxicity symptoms like those seen with excessive vitamin A intake.
On the other hand, herbal supplements can also cause side effects, with some even capable of interacting negatively with prescription medications.