Disease prevention may also justify in some people's mind the need for excessive use of dietary supplements. A good example of these ideas or beliefs leading to harmful outcomes is the toxic effects that excessive vitamins and minerals have on small children. In 1996, more than 50,000 reports from poison control centers identified children younger than 6 swallowing excessively large doses of supplements. High-potency iron supplements are especially toxic and are the leading cause of accidental ingestion fatalities among children. Mild overdoses can cause gastrointestinal distress, nausea, and black diarrhea that reflects gastric bleeding.
Large doses can cause bloody diarrhea, shock, liver damage, coma, and death.
Long term excessive use of vitamins, minerals , and herbal products may lead to disease and may be difficult for the medical profession to properly diagnose. Sometimes the effects develop subtly and progress slowly. One individual was diagnosed with liver disease which was related to taking a vitamin A supplement. A supplement was removed from her diet, the condition cleared up. Many people today who have health problems choose supplements but the situation may have resulted from lifestyle choices.