Sometimes called a “cell protector”, the name manganese comes from the Greek word for magic, because it was thought to have magical properties. Manganese is a metal that occurs widely in plant and animal tissues; it is called a trace element because it is only found in very small quantities in the human body. Our bodies store approximately 20mg of manganese, mostly in the bones.
Manganese is necessary for bone growth, reproduction, skin, ligament formation, blood clotting, wound healing, peak brain function and the proper metabolism of cholesterol, sugars and insulin. It is also an enzyme activator and is said to help in the utilization of vitamin B1. An important antioxidant, manganese is one of the minerals required to form SOD (superoxide dismutase), one of the “bodyguard” enzymes that protects against unstable, cell-damaging free radicals. Trace Elements, Micronutrients and Free Radicals, 1992, pp.107-27]
Although no US RDA has been established for manganese, the National Research Council has estimated that a safe and adequate daily dietary intake of manganese for adults should range from 2 to 5mg per day. Although many people consume less than this, obvious deficiencies are uncommon.
Manganese is poorly absorbed orally and so should be given long term and/or by injection when indicated. While only 5mg is needed per day, the patient may need as much as 300mg of manganese in the gluconate form to attain the normal blood level of 15ppb.
Manganese sulfate is the most commonly used form, but it is also the most poorly absorbed.. The more bioavailable forms of manganese include citrate, gluconate, ascorbate, or other amino acid chelates, but will cost more than the sulfate form. Other poorly absorbed forms of manganese include manganese oxide and manganese chloride.
Dosing for manganese from organic chelate forms such as ascorbate, gluconate, aspartate, citrate, picolinate, or other amino acid chelates should range from 5 to 50mg per day, with 10 to 25mg being more than adequate. Dosing for manganese sulfate, the most common form, along with manganese oxide and manganese chloride, can range from 50 to over 100mg per day.
Taking iron, magnesium or calcium supplements can inhibit absorption of manganese even if there is enough present in your diet.