Role of manganese in human body

Manganese is a micro mineral with a broad range of functions. In our body manganese is mainly concentrated in kidneys, bones, pancreas and liver. Manganese is important for normal growth and development. It is essential for the activation of several enzymes involved in the synthesis of cartilage.
It is also a constituent of certain enzymes involved in the protection of tissues from free radical damage.
It is necessary to both thyroid and sex hormones production. It is also essential for the manufacture of cholesterol and production of insulin.
It is also needed for glucose storage in the liver and for healthy bone growth. Manganese is needed for wound healing as it increases collagen production. It also increases vitamin absorption, improves cognitive function, regulates glucose metabolism and improves digestion.

Deficiency

Low levels of manganese in the body can result in changes in carbohydrate and fat metabolism, impaired glucose tolerance, bone deformation, stunted growth, decreased serum cholesterol levels, skin rash, elevated blood calcium and phosphorus levels,  infertility, seizures, weakness, nausea or vomiting, dizziness, hearing loss, anaemia, weak hair and nails, convulsions, and blindness or paralysis in infants.

Excess

Although manganese toxicity is rare, high levels of manganese sometimes may cause leg cramps, hallucinations, severe mood swings, headaches, tremors, and difficulty in walking.

Tolerable Upper Limit (UL) of manganese for adults is 11 mg per day. Consuming more than 11 mg per day may have harmful side effects.

Recommended Dosage: The average dietary intake of manganese ranges from 2.1 to 2.3 mg per day for men and 1.6 to 1.8 mg per day for women.

Adequate Intake (AI) levels of manganese are:

Infants: birth to 6 months -- 3 mcg;
7 to 12 months -- 600 mcg;
Children:       1 to 3 years --- 1.2 mg;
                          4 to 8 years ---1.5 mg;
Boys:              9 to 13 years -- 1.9 mg;
                        14 to 18 years -- 2.2 mg;
Girls:              9 to 18 years -- 1.6 mg.
Males:   19 years and older-- 2.3 mg
Females:19 years and older-- 1.8 mg
                   Pregnant women -- 2 mg
                  Lactating women -- 2.6 mg

The daily Tolerable Upper Intake Levels (UL), of manganese are:

Children 1 to 3 years -- 2 mg;
4 to 8 years -- 3 mg;
9 to 13 years-- 6 mg
14 to 18 years (including pregnant and breastfeeding women) -- 9 mg.

Dietary Sources

Foods rich in manganese include:
Fruits such as pineapple, grapes, kiwi, berries, and almonds.
Vegetables like dark leafy greens, beets, sweet potatoes, celery, squash and carrots
Nuts and seeds, Legumes, Egg yolks
Soy products like tofu and tempeh
Whole grains such as brown rice, oatmeal, raisin bran, quinoa, barley, wheat
Herbs and spices like peppermint, cinnamon, cloves and thyme
Garlic, Seaweed, Molasses, Syrup and tea.

Our body stores up to about 20 mg of manganese in kidneys, liver, pancreas and bones.

• Clinically, manganese is used for strains, sprains, and inflammation.
• Iron absorption can be decreased due to excess manganese.
• People who receive nutrition intravenously (by IV) are at an increased risk of excess manganese.
• Welders, steelworkers, and miners can have symptoms similar to Parkinson’s disease due to the exposure to toxic levels of manganese.