The mineral manganese is needed in trace amounts, however, it is one of the most common elements found in the earth's crust - it serves as a co-factor in many enzymatic reactions. Manganese can be found in atmospheric dust, in rain water, in fresh and sea water as well as in all animal and plant tissues. There is not a single sample of human tissue which does not contain a little manganese - some trace of the element can be detected in all tissue samples. As manganese serves as a co-factor in several important enzyme systems, it is considered to be an essential trace mineral and some amount is required in the diet. The reactions in which manganese functions as a co-factor include the synthesis of many types of protein, in the enzymatic formation of nucleic acids DNA and RNA, and in the synthesis of cartilage tissue. The mineral may be vital in processes involving the metabolism of fats, and it is known that manganese plays a role in the utilization of the insulin hormone. A preparation made from alfalfa, which is high in manganese, is reportedly a traditional African folk medicine which is still used as a treatment for diabetes and blood sugar related disorders.
Manganese deficiency can also lead to the impairment of growth, it can disrupt the reproductive processes, it can induce a glucose tolerance, it can affect egg shell formation, it can affect the clotting of blood and it can also lead to the development of deformities in the skeletal system and induce a loss of muscular coordination in the body. The immune response of test animals has also been found to be lowered by a deficiency of manganese deficiency in the body of the animals. Though, once believed to be genetic mutations, the deficiency caused by manganese has been found to be responsible for certain birth defects affecting animals. This effect was erased in the offspring by supplying manganese supplements to the pregnant test animals.
The physical symptoms of manganese deficiency in humans were an accidental discovery during a test diet, the manganese was mistakenly left out and this induced deficiency symptoms in the test subjects. Manganese deficiency symptoms experienced by the volunteers in the test include sudden weight loss, skin disorders like dermatitis, spells of nausea, the slow growth of hair and beard with changes in the color of the hair, the manganese deficiency also produced symptoms like very low levels of cholesterol in the blood.
The manganese levels in the blood of schizophrenia patients particularly those who are affected by tardive dyskinesia have been found to be abnormally low. Tardive dyskinesia is a side effect of psychiatric medication and it was found to be preventable by supplementing manganese at doses of fifteen to sixty mg daily in all such people affected by the condition.
Manganese is found in good amounts from natural sources such as whole grains, as well as wheat germ and bran, in garden peas, in beet tops, in fruits like pineapple, as well as in tea, ginger and the sage herb. Good sources of manganese also include wines, different kinds of nuts, all types of green leafy vegetables and most fruits. Some types of multi-mineral supplements also include manganese as an additive.
The levels of manganese normally considered safe and sufficient in the diet is about 2.5mg - 5mg of manganese daily - the majority of people actually consume less than this amount of the mineral in the daily diet. Clear deficiencies of the mineral are nevertheless quite rare. Low blood levels of manganese, suggestive of a deficiency also tend to be evident in individuals affected by osteoporosis.
It is still unclear if the majority of people would actually benefit from manganese supplementation as dietary sources are often adequate. Those wishing to supplement with manganese will be satisfied with the 5mg - 15 mg manganese often found in many high-potency multivitamin or multi-mineral supplements - these amounts are generally considered to be a reasonable and safe for long term supplemental use.
No toxic effects have been found to be affected in the human body by the amounts of manganese normally present in most supplements - usually 5mg - 20 mg, these supplements can be considered to be very safe for long term use. Some very rare side effects including dementia and various psychiatric symptoms can result from the excessive consumption of manganese supplements. The excretion of manganese from the body of individuals with liver cirrhosis may possibly be disrupted according to the findings of preliminary research. The use of supplemental manganese by individuals affected with cirrhosis is not recommended until more is known about its effects on the liver.
The rate of absorption of manganese in the body is also affected by several minerals like calcium and iron, and perhaps zinc - these essential minerals may reduce the absorption rate of manganese into the body. For example, the minerals zinc and copper work along side manganese in activating superoxide dismutase - an enzyme.