Manganese is a metal that occurs widely in plant and animal tissues. It is called a trace element because it is found in very small quantities in the human body. Our bodies store approximately 20 milligrams of manganese, mostly in the bones. Manganese aids in forming connective tissue, fats and cholesterol, bones, blood-clotting factors, and proteins. It is also necessary for normal brain function. Manganese is a component of manganese superoxide dismutase (MnSOD), an antioxidant that protects the body from toxic substances. It is easy to obtain adequate amounts of manganese from the diet.

The following illnesses may be affected by manganese:

• Diabetes. People who have diabetes sometimes have significantly less manganese than healthy people. Manganese decreases blood sugar levels in some people with diabetes.
• Rheumatoid arthritis. People with rheumatoid arthritis (inflammation of the joints) can have low levels of MnSOD, which helps protect the joints from damage during inflammation. Manganese supplementation increases MnSOD activity.
• Epilepsy. An important study in the early 1960s demonstrated that manganese-deficient rats were more susceptible to seizures and had electroencephalograms (EEGs) consistent with seizure activity.
• Schizophrenia. People who have schizophrenia may also respond well to manganese supplementation.
• Osteoporosis. Bone loss occurs more rapidly after menopause and can lead to osteoporosis (brittle, thin, bones). Manganese, and other trace elements, increase bone density in postmenopausal women.
• Other conditions. Manganese is also used to treat hardening of the arteries (atherosclerosis), osteoarthritis, tinnitus, and hearing loss.

• Nuts (especially pecans and almonds)
• Wheat germ and whole grains
• Unrefined cereals
• Leafy vegetables
• Liver
• Kidney
• Legumes (peanuts, beans)
• Dried fruits

Refined grains, meats, and dairy products contain very small amounts of manganese. Unrefined foods, such as whole grain breads and cereals, are higher in manganese.

Manganese is available in a wide variety of forms including manganese salts (sulfate and gluconate) and manganese chelates (aspartate, picolinate, fumarate, malate, succinate, citrate, and amino acid chelate). It is available in tablets or capsules, usually along with other vitamins and minerals.

The exact amount of manganese required by the human body is not known. The estimated safe and adequate daily intakes for dietary manganese established by the Food and Nutrition Board of the National Research Council are listed below.

These estimates are based on the assumption that most dietary intakes fall within the range indicated and do not result in either deficiency or toxicity. In therapeutic use for epilepsy, inflammation, or diarrhea, the dose may be increased by the healthcare professional up to three-to-sixfold. Supplementation, particularly for children, should only be undertaken with direction from the healthcare provider.

Pediatric

• Infants birth to 6 months: 0.3 mg
• Infants 7 to 12 months: 0.6 mg
• Children 1 to 3 years: 1.2 mg
• Children 4 to 8 years: 1.5 mg
• Males 9 to 13 years: 1.9 mg
• Males 14 to 18 years: 2.2 mg
• Females 9 to 18 years: 1.6 mg

Adult

• Males 19 years and older: 2.3 mg
• Females 19 years and older: 1.8 mg
• Pregnant females: 2 mg
• Breastfeeding females: 2.6 mg

Excessive intake of manganese can produce toxic effects. You should not regularly exceed the estimated safe and adequate daily intakes for manganese listed above.

There has been at least one case report of an interaction between haloperidol and manganese that resulted in neuropsychiatric side effects. Therefore, it would be wise to refrain from taking manganese if you are currently taking haloperidol. Your healthcare provider should monitor blood levels of both haloperidol and manganese closely.

Reserpine, a medication used to treat high blood pressure, may decrease manganese levels.

Davis CD, Greger JL. Longitudinal changes of manganese-dependent superoxide dismutase and other indexes of manganese and iron status in women. Am J Clin Nutr. 1992;55:747–752.

Deimling MJ, Schnell C. Interaction between manganese and phenobarbital on hexobarbital hypnosis in the male rat. Res Commun Chem Pathol Pharmacol. 1983;41(1):165-168.

el-Yazigi A, Hannan N, Raines DA. Urinary excretion of chromium, copper, and manganese in diabetes mellitus and associated disorders. Diabetes Res. 1991;18:129–134.

Fell JM, Reynolds AP, Meadows N, et al. Manganese toxicity in children receiving long-term parenteral nutrition. Lancet. 1996;347:1218–1221.

Finley JW, Davis CD. Manganese deficiency and toxicity: are high or low dietary amounts of manganese cause for concern? Biofactors. 1999;10(1):15-24.

Friedman E, ed. Biochemistry of the Essential Ultratrace Elements. New York, NY: Plenum Press; 1984.

Goering PL, Haassen CD. Mechanism of manganese-induced tolerance to cadmium lethality and hepatotoxicity. Biochem. Pharmacol. 1985;34:1371-1379.

Ingersoll RT, Montgomery EB Jr, Aposhian HV. Central nervous system toxicity of manganese. II: Cocaine or reserpine inhibit manganese concentration in the rat brain. Neurotoxicol. 1999; 20(2-3):467-476.

Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press; 2001

Itokawa Y. Trace elements in long-term total parenteral nutrition [in Japanese]. Nippon Rinsho. 1996;54:172–178.

Johnson MA, Smith MM, Edmonds JT. Copper, iron, zinc, and manganese in dietary supplements, infant formulas, and ready-to-eat breakfast cereals. Am J Clin Nutr. 1998;67(suppl):1035S–1040S.

Krause, MV., & Mahan, L.K. Food, Nutrition, and Diet Therapy. 7th ed. Philadelphia, Pa: WB Saunders Co., 1984.

Mehta R, Reilly JJ. Manganese levels in a jaundiced long-term total parenteral nutrition patient: Potentiation of haloperidol toxicity?: Case report and literature review. J Parenter Enter Nutr. 1990;14(4):428-430.

Orten JM., Neuhaus OW, eds. Human Biochemistry. 10th ed. St. Louis, MO: The C.V. Mosby Co; 1982.

Pasquier C, Mach PS, Raichvarg D, Sarfati G, Amor B, Delbarre F. Manganese-containing superoxide-dismutase deficiency in polymorphonuclear leukocytes of adults with rheumatoid arthritis. Inflammation. 1984;8:27–32.

Saltman PD, Strause LG. The role of trace minerals in osteoporosis. J Am Coll Nutr. 1993;12:384–389.

Shils ME, Olsen JA, Shike M, eds. Modern Nutrition in Health and Disease. 8th ed. Media, Pa: Williams and Wilkins Co; 1994:1.

Shvets NV, Kramarenko LD, Vydyborets SV, Gaidukova SN. Disordered trace element content of the erythrocytes in diabetes mellitus [in Russian]. Lik Sprava. 1994;1:52–55.

Somer E. The Essential Guide to Vitamins & Minerals. New York, NY: HarperCollins Publishers; 1992.

Whitney EN, Hamilton EN. Understanding Nutrition. 3rd ed. St. Paul, Minn: West Publishing Co; 1984.