Manganese is an essential trace element that is naturally present in many foods and available as a dietary supplement. Manganese is a cofactor for many enzymes, including manganese superoxide dismutase, arginase, and pyruvate carboxylase. Through the action of these enzymes, manganese is involved in amino acid, cholesterol, glucose, and carbohydrate metabolism; reactive oxygen species scavenging; bone formation; reproduction; and immune response. Manganese also plays a role in blood clotting and hemostasis in conjunction with vitamin K. (1) Manganese and calcium in combination may help improve premenstrually (PMS) symptoms. (2) The human body contains about 10 to 20 mg manganese, of which 25% to 40% are in the bones. The liver, pancreas, kidney, and brain also contain manganese. 

Manganese is essential for bone health, including bone development and maintenance. When combined with the nutrients calcium, zinc and copper, manganese supports bone mineral density. Manganese supplementation can increase both bone mineral density and bone formation. (3, 4) In one small clinical trial, supplementation with calcium (1,000 mg) plus trace minerals (5 mg manganese, 15 mg zinc, and 2.5 mg copper) for 2 years improved spinal bone density compared to placebo in 59 healthy postmenopausal women (mean age 66 years). (5) In another study, 10 women with osteoporosis (mean age, 69.3 years) had lower serum manganese levels (20 mcg/L) than 20 women (mean age, 64.5 years) who did not have osteoporosis (40 mcg/L). (6) 

Manganese also helps activate many enzymes in metabolism and plays a role in a variety of chemical processes in your body. It helps with protein and amino acid digestion and utilization, as well as the metabolism of cholesterol and carbohydrates. Manganese helps absorb and utilize a number of vitamins like vitamins B, C, and E and minerals like magnesium. (7, 8) This is due to the role of manganese in the enzymatic reactions that are required to absorb and utilize vitamins taken in from food. It ensures a smooth liver function and is an essential part of the metabolism and glutamine. Manganeses is the most abundant amino acid in the body and a key part of DNA polymerase. 

Additionally, it works as a cofactor or helper, in development, reproduction, energy production, immune response and the regulation of brain activity. (9) Manganese is essential for the healthy functioning of the brain and it is also used to treat specific nervous disorders. One way is through its antioxidant properties, particularly its role in the function of the powerful antioxidant superoxide dismutase (SOD). Manganese is a part of the antioxidant enzyme superoxide dismutase (SOD), which is arguably one of the most important antioxidants in your body. (10) Antioxidants help protect against free radicals, which are molecules that can cause damage to cells in your body. Free radicals are believed to contribute to aging, heart disease and some cancers. (11) Oxidation byproducts like free radicals are everywhere in the body, and the brain can be negatively affected just as easily as other parts of the body. Therefore powerful antioxidants like SOD are required. Apart from its antioxidant role, manganese can also bind with neurotransmitters and stimulate faster or more efficient transmission of electrical impulses throughout the body, in effect, speeding up the cognitive function. SOD specifically helps combat the negative effects of free radicals by converting superoxide, one of the most dangerous free radicals, into smaller molecules that won’t damage your cells. (12) Manganese is also heavily concentrated in the pancreas and involved in the production of insulin, which removes sugar from your blood. Consequently, manganese may contribute to the proper secretion of insulin and help stabilize blood sugar. (13) 

References: 

1. Aschner JL, Aschner M. Nutritional aspects of manganese homeostasis. Mol Aspects Med. 2005 Aug-Oct; 26 (4-5): 353-62. 

2. Penland JG, Johnson PE. Dietary calcium and manganese effects on menstrual cycle symptoms. Am J Obstet Gynecol. 1993 May; 168 (5): 1417-23. 

3. Saltman PD, Strause LG. The role of trace minerals in osteoporosis. J Am Coll Nutr. 1993 Aug; 12 (4): 384-9. 

4. Bae YJ, Kim MH. Manganese supplementation improves mineral density of the spine and femur and serum osteocalcin in rats. Biol Trace Elem Res. 2008 Jul; 124 (1): 28-34. 

5. Strause L, Saltman P, Smith KT, Bracker M, Andon MB. Spinal bone loss in postmenopausal women supplemented with calcium and trace minerals. J Nutr. 1994 Jul; 124 (7): 1060-4. 

6. Reginster Jean-Yves, Strause LG, Saltman P, Franchimont P. Trace elements and postmenopausal osteoporosis: a preliminary report of decreased serum manganese Medical Science Research. 1988; 16:337-338. 

7. Chen P, Bornhorst J, Aschner M. Manganese metabolism in humans. Front Biosci (Landmark Ed). 2018 Mar 1; 23:1655-1679. 

8. Brittmarie Sandström. Micronutrient interations: Effects on absorption and bioavailability. British Journal of Nutrition, 2001; 85 (S2), S181-S185.

9. Chen P, Bornhorst J, Aschner M. Manganese metabolism in humans. Front Biosci (Landmark Ed). 2018 Mar 1; 23:1655-1679. 

10. Holley AK, Bakthavatchalu V, Velez-Roman JM, St Clair DK. Manganese superoxide dismutase: guardian of the powerhouse. Int J Mol Sci. 2011; 12 (10): 7114-62. 

11. Lien Ai Pham-Huy, Hua He, Chuong Pham-Huy. Free Radicals, Antioxidants in Disease and Health Int J Biomed Sci. 2008 Jun; 4 (2): 89–96. 

12. Chang Li, Hai-Meng Zhou. The Role of Manganese Superoxide Dismutase in Inflammation Defense Enzyme Res. 2011; 2011: 387176. 

13. Lee SH, Jouihan HA, Cooksey RC, Jones D, Kim HJ, Winge DR, McClain DA. Manganese supplementation protects against diet-induced diabetes in wild type mice by enhancing insulin secretion. Endocrinology. 2013 Mar; 154 (3): 1029-38.