Taking megadoses of vitamins
Ex:
Vitamin D: risk of high calcium levels.
An overdose of vitamin B12 is almost impossible.un overdose of vitamin B12 is unlikely because the body removes unused quantities very easily.
Vitamin A: The hypervitaminose causes nausea, abdominal pain, diarrhea and weight loss. The nervous system and muscular system may also be affected and cause symptoms such as loss of appetite, irritability, nervousness, fatigue, insomnia, headaches and muscle weakness:
