Lysine Contraindications Lysine may raise levels of cholesterol in the blood. It is unusual for anyone to be deficient in copper and to require supplements. Possible Adverse Effects Doses larger than 1,000 IU a day are not recommended. Adverse Effects Iron supplements are a leading cause of fatal poisonings in children. Adults should keep iron tablets in a locked cabinet out of reach of young children.
Iron deficiency is the most common nutrient deficiency in the United States.
The groups at highest risk are infants under two years of age, teenage girls, pregnant women and the elderly. Extreme fatigue is a primary symptom of anemia, the last stage of iron deficiency. However, iron overload can result in heart disease, infection and possibly even cancer.5 Iron supplements, therefore, should only be used when tests show a deficiency exists.4 Magnesium Contraindications People with kidney disease or severe heart disease should not use magnesium supplements except under a physician's supervision.5 Possible Adverse Effects Because healthy kidneys can excrete six grams of magnesium a day, it is difficult to overdose. But toxic levels can result from the abuse of magnesium-containing laxatives. Even small doses of magnesium can cause diarrhea in some people.