Vitamins, Minerals and Dietary Supplements
What is manganese?
Manganese is a trace element and essential mineral. In its natural state, it is grayish-white in color and resembles iron, but it is not magnetic. It is absorbed in the small intestine and is stored in small amounts in the bones, pituitary gland, pancreas and liver.
Why do we need it?
Manganese is needed for the formation of healthy skin, nerves, bones and cartilage. It also works in conjunction with zinc and copper to activate an antioxidant named superoxide dismutase, which prevents free radicals from destroying cell organs.
In addition, manganese plays an important role in the synthesis of cholesterol and fatty acids, and is essential for the utilization of choline, thiamin, biotin, and vitamins C and E. It helps activate enzymes that regulate blood sugar, energy metabolism and function of the thyroid gland.
How much manganese should I take?
There is currently no recommended daily allowance (RDA) for manganese. However, the National Academy of Sciences has deemed the following amounts to be safe and adequate in a normal diet:
- Adult men: between 2-5 milligrams/day
- Adult women: between 2-5 milligrams/day
- Children aged 7-10: between 2-3 milligrams/day
- Infants: between 0.3-1.0 milligrams/day
- Pregnant/lactating women: between 2-5 milligrams/day
What are some good sources of manganese?
The best dietary sources of manganese are nuts, whole grains, dried fruits, pineapples and leafy green vegetables. Beets, beans and brown rice are other good sources.
What can happen if I don't get enough manganese?
Manganese deficiency is extremely rare. Some animal studies have shown that a diet devoid of manganese can lead to slow or stunted growth, skeletal abnormalities and paralysis. Other studies have linked manganese deficiency to osteoporosis, loss of hair color, and impaired growth of hair and nails.
What can happen if I take too much?
Excessive amounts of manganese can lead to side effects such as dementia, hallucinations and psychiatric disorders, a condition sometimes known as "manganese madness." Research has also suggested that individuals with cirrhosis may not be able to properly excrete manganese. Patients with this condition should not take manganese supplements.
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