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Manganese

Evidence Level
Limited
4 Clinical Trials
4 Documented Benefits
2/5 Evidence Score

Manganese is an essential trace mineral. It is a cofactor for enzymes such as manganese superoxide dismutase (an antioxidant enzyme), arginase and pyruvate carboxylase, and through them it takes part in amino acid, glucose and cholesterol metabolism, bone formation and blood clotting. Shellfish, nuts, whole grains, legumes, leafy vegetables and tea supply it, and deficiency is very rare. Adults need about 1.8 to 2.3 mg a day, and the upper limit is 11 mg. Human evidence for supplements is thin: one small trial raised an antioxidant enzyme marker at a dose above the upper limit, and bone and joint trials only tested manganese inside multi-ingredient formulas. Excess manganese, mostly from inhaled dust or contaminated water, can harm the nervous system.

Studied Dose Adequate intake: 2.3 mg a day for men and 1.8 mg for women; upper limit 11 mg a day. Trials used 5 mg a day with calcium, zinc and copper (bone) and 15 mg a day, above the upper limit, in an enzyme marker study.
Active Compound Manganese as amino acid chelates (such as bisglycinate), gluconate, picolinate, sulfate, citrate or chloride. Labels list elemental manganese, and no data compare how well these forms are absorbed.
Deficiency information View details

Manganese deficiency is very rare in humans, and its signs have not been firmly established. Most people get enough from shellfish, nuts, whole grains, legumes, leafy vegetables and tea. Excess manganese, mainly from inhaled dust or contaminated water, is the better documented problem.

Common symptoms

  • Signs of deficiency in humans have not been firmly established
  • Very limited evidence suggests skin rashes, hair depigmentation, lower serum cholesterol and higher alkaline phosphatase in men
  • Altered mood and increased premenstrual pain have been reported in women
  • Bone demineralization and poor growth have been suggested in children

At-risk groups

  • No known groups of people are likely to have inadequate manganese intakes
  • People with chronic liver disease or iron deficiency are more vulnerable to manganese excess, not deficiency
When to see a doctor: Low manganese from diet alone is very rare, so symptoms blamed on it usually have another cause. Seek care for tremor, unsteadiness, muscle spasms or new mood and memory changes, especially with welding or mining work, high-manganese well water or liver disease, because these can signal manganese excess. Talk to a doctor before taking more than 11 mg a day.
Explore related deficiencies →
Sources: NIH ODS: Manganese Health Professional Fact Sheet · DRI: Manganese (NCBI Bookshelf NBK222332)

Benefits

Cofactor for the antioxidant enzyme MnSOD

Manganese is a cofactor for manganese superoxide dismutase (MnSOD), an enzyme that clears reactive oxygen species. In a 124-day trial of 47 women, 15 mg a day, above the 11 mg upper limit, raised MnSOD activity in white blood cells and serum manganese. This is a single small trial of an enzyme marker, not of a health outcome.

Supported by Trial 2

Bone formation

Manganese is a cofactor for enzymes involved in bone formation, and 25% to 40% of the body's manganese is in bone. No trial has tested manganese alone for bone. In a 2-year trial of 59 postmenopausal women, calcium plus zinc, copper and 5 mg manganese limited spinal bone loss versus placebo, but trace minerals alone did not differ significantly.

Supported by Trial 1

Joint comfort in combination formulas

Manganese ascorbate is part of some glucosamine and chondroitin formulas. In a 16-week pilot crossover trial of 34 Navy men and a 6-month trial of 93 people with knee osteoarthritis, such a combination eased knee symptoms, mainly in mild to moderate cases. Manganese was never tested alone, so these results mostly reflect the other ingredients.

Supported by Trial 4, Trial 3

Amino acid and glucose metabolism

Manganese is a cofactor for arginase, part of the urea cycle that handles nitrogen from protein, and for pyruvate carboxylase, which helps the body make glucose. Human trials of manganese for blood sugar are lacking, and studies of blood manganese and diabetes disagree.

Supported by Trial 1, Trial 2

Mechanism of action

1

MnSOD and reactive oxygen species

Manganese is a cofactor for manganese superoxide dismutase, one of the enzymes that scavenge reactive oxygen species. White blood cell MnSOD activity rose when women took manganese supplements, so it is used as a marker of manganese exposure.

2

Bone formation

Manganese is a cofactor for several enzymes involved in bone formation. In animals, deficiency impairs bone formation and lowers bone density, and supplementation raises both; human data are very limited.

3

Metabolic enzymes and clotting

Arginase and pyruvate carboxylase depend on manganese, linking it to amino acid, glucose and carbohydrate metabolism. Manganese also plays a role in blood clotting together with vitamin K.

4

Absorption and balance

Adults absorb only about 1% to 5% of dietary manganese, more when intake is low and less when it is high. More than 90% of absorbed manganese leaves through bile, and higher iron status is linked to lower manganese absorption.

Clinical trials

1
Calcium and trace minerals for spinal bone
PubMed

2-year double-blind placebo-controlled trial: calcium 1,000 mg, trace minerals (zinc 15 mg, manganese 5 mg, copper 2.5 mg), both, or placebo (Strause et al. 1994, J Nutr)

59 healthy postmenopausal women, mean age 66

Spinal bone density changed by -3.53% on placebo, -1.89% on trace minerals only, -1.25% on calcium only and +1.48% on calcium plus trace minerals. The only significant group difference was calcium plus trace minerals versus placebo (P = 0.0099), so manganese's own effect cannot be separated.

2
Manganese and MnSOD activity
PubMed

124-day supplementation study: placebo, iron 60 mg, manganese 15 mg, or both daily (Davis et al. 1992, Am J Clin Nutr)

47 women

Manganese supplementation significantly raised lymphocyte MnSOD activity and serum manganese from baseline, with no change in urinary manganese or iron status. The 15 mg dose is above today's 11 mg upper limit.

3
Glucosamine, chondroitin and manganese ascorbate
PubMed

16-week randomized double-blind placebo-controlled crossover pilot: glucosamine HCl 1,500 mg, chondroitin sulfate 1,200 mg and manganese ascorbate 228 mg a day (Leffler et al. 1999, Mil Med)

34 US Navy men with chronic knee or low back pain and degenerative joint disease on X-ray

Knee symptom scores (-16.3%, p = 0.05), pain on a visual scale and examination scores improved; running times did not change. The trial neither showed nor excluded a benefit for the low back. Manganese was not tested alone.

4
Combination formula for knee osteoarthritis
PubMed

Randomized placebo-controlled 6-month trial of glucosamine HCl 1,000 mg, chondroitin sulfate 800 mg and manganese ascorbate 152 mg twice daily (Das et al. 2000, Osteoarthritis Cartilage)

93 adults with knee osteoarthritis

People with mild or moderate disease (72) improved on the Lequesne index at 4 and 6 months (52% vs 28% responders); those with severe disease (21) did not. Adverse events were similar (17% vs 19%). Manganese was not tested alone.

Side effects and drug interactions

Common Potential side effects

No evidence shows manganese toxicity from high dietary intake. Stay within the 11 mg a day adult upper limit for supplements unless a doctor supervises use.
Manganese toxicity has occurred with long-term inhalation of manganese dust or fumes (welding, mining) and with drinking water high in manganese. It mainly affects the nervous system, causing tremor, muscle spasms, mood and memory changes and, in severe cases, Parkinson-like movement problems.
People with chronic liver disease clear manganese poorly and are more susceptible to toxicity, and iron deficiency increases manganese absorption.

Important Drug interactions

Manganese is not known to have any clinically relevant interactions with medications, according to the NIH Office of Dietary Supplements.
Iron: higher iron intake and iron status are linked to lower manganese absorption.

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Frequently asked questions about Manganese

How much manganese should I take?

The adequate intake for adults is 2.3 mg a day for men and 1.8 mg for women. Most people get enough from foods such as shellfish, nuts, whole grains, legumes and leafy greens, so high-dose supplements are rarely needed. Do not exceed 11 mg a day.

What is manganese good for?

Manganese is an essential trace mineral that enzymes need for amino acid, cholesterol, glucose and carbohydrate metabolism, for clearing reactive oxygen species (as part of manganese superoxide dismutase), for bone formation and for blood clotting. Trials of manganese supplements on their own for health outcomes are lacking.

Can you take too much manganese?

Yes. No toxicity has been shown from food, but manganese toxicity has occurred from inhaled dust and fumes and from drinking water high in manganese, and it affects the nervous system. People with liver disease are more vulnerable. Stay at or below 11 mg a day from supplements unless a doctor advises otherwise.

Is manganese the same as magnesium?

No, they are different minerals that are often confused because of their similar names. Magnesium is needed in hundreds of milligrams a day for muscle and nerve function and energy production, while manganese is a trace mineral needed in about 2 mg. Check labels carefully.

What is Manganese?

Manganese is an essential trace mineral. It is a cofactor for enzymes such as manganese superoxide dismutase (an antioxidant enzyme), arginase and pyruvate carboxylase, and through them it takes part in amino acid, glucose and cholesterol metabolism, bone formation and blood clotting.

What is Manganese used for?

Manganese is researched primarily for Bone Health, Antioxidant, and Joint Health. Manganese is a cofactor for manganese superoxide dismutase (MnSOD), an enzyme that clears reactive oxygen species. In a 124-day trial of 47 women, 15 mg a day, above the 11 mg upper limit, raised MnSOD activity in white blood cells and seru…

What are the signs of Manganese deficiency?

Manganese deficiency is very rare in humans, and its signs have not been firmly established. Most people get enough from shellfish, nuts, whole grains, legumes, leafy vegetables and tea. Excess manganese, mainly from inhaled dust or contaminated water, is the better documented problem.

Is Manganese safe, and does it have side effects?

Side effects and cautions reported for Manganese include: No evidence shows manganese toxicity from high dietary intake. Stay within the 11 mg a day adult upper limit for supplements unless a doctor supervises use. It may also interact with some medications. Manganese is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Manganese interact with any medications?

Possible interactions include: Manganese is not known to have any clinically relevant interactions with medications, according to the NIH Office of Dietary Supplements. Iron: higher iron intake and iron status are linked to lower manganese absorption. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Manganese?

NutraSmarts rates the evidence for Manganese as Limited (2 out of 5). It is backed by 4 study summaries and 9 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(9 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Roels HA, Bowler RM, Kim Y, Claus Henn B, Mergler D, Hoet P, Gocheva VV, Bellinger DC, Wright RO, Harris MG, Chang Y, Bouchard MF, Riojas-Rodriguez H, Menezes-Filho JA, Téllez-Rojo MM. Manganese exposure and cognitive deficits: a growing concern for manganese neurotoxicity. Neurotoxicology. 2012;33(4):872-80. doi: 10.1016/j.neuro.2012.03.009.PubMedUsed to support: Symposium summary on manganese and the brain: cognitive and motor deficits in manganese-exposed welders and workers, and studies linking excess manganese from air and drinking water to poorer cognitive performance in children.
  2. O'Neal SL, Zheng W. Manganese Toxicity Upon Overexposure: a Decade in Review. Curr Environ Health Rep. 2015;2(3):315-28. doi: 10.1007/s40572-015-0056-x.PubMedUsed to support: Review of manganese toxicity: exposure causes signs resembling Parkinson's disease, and beyond occupational exposure it can come from nutritional sources, contaminated foods, infant formula, water, soil and air.
  3. Chen P, Totten M, Zhang Z, Bucinca H, Erikson K, Santamaría A, Bowman AB, Aschner M. Iron and manganese-related CNS toxicity: mechanisms, diagnosis and treatment. Expert Rev Neurother. 2019;19(3):243-260. doi: 10.1080/14737175.2019.1581608.PubMedUsed to support: Review of iron and manganese brain toxicity: both are essential enzyme cofactors and nutritional deficiency is rare; overload is linked to neurological disorders through oxidative stress and mitochondrial dysfunction.
  4. Flynn MR, Susi P. Neurological risks associated with manganese exposure from welding operations--a literature review. Int J Hyg Environ Health. 2009;212(5):459-69. doi: 10.1016/j.ijheh.2008.12.003.PubMedUsed to support: Literature review of welding fume exposure: identified 78 probable or possible and 19 more possible cases of occupational manganism among manganese-exposed welding workers.
  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;124(7):1060-4. doi: 10.1093/jn/124.7.1060.PubMedUsed to support: 2-year trial in 59 postmenopausal women. Calcium plus zinc, manganese (5 mg) and copper limited spinal bone loss versus placebo; trace minerals alone did not differ significantly from placebo.
  6. 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(3):747-52. doi: 10.1093/ajcn/55.3.747.PubMedUsed to support: 124-day study in 47 women. Manganese 15 mg a day raised lymphocyte MnSOD activity and serum manganese without changing iron status.
  7. Leffler CT, Philippi AF, Leffler SG, Mosure JC, Kim PD. Glucosamine, chondroitin, and manganese ascorbate for degenerative joint disease of the knee or low back: a randomized, double-blind, placebo-controlled pilot study. Mil Med. 1999;164(2):85-91.PubMedUsed to support: 16-week crossover pilot in 34 Navy men. A glucosamine, chondroitin and manganese ascorbate combination relieved knee symptoms; low back results were inconclusive; manganese was not tested alone.
  8. Das A Jr, Hammad TA. Efficacy of a combination of FCHG49 glucosamine hydrochloride, TRH122 low molecular weight sodium chondroitin sulfate and manganese ascorbate in the management of knee osteoarthritis. Osteoarthritis Cartilage. 2000;8(5):343-50. doi: 10.1053/joca.1999.0308.PubMedUsed to support: 6-month trial in 93 adults with knee osteoarthritis. A glucosamine, chondroitin and manganese ascorbate combination improved the Lequesne index in mild to moderate but not severe disease.
  9. Office of Dietary Supplements, National Institutes of Health. Manganese: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements. 2021;Updated March 29, 2021. https://ods.od.nih.gov/factsheets/Manganese-HealthProfessional/.SourceUsed to support: Not PubMed-indexed: NIH fact sheet. Gives adult adequate intakes (2.3 mg men, 1.8 mg women) and the 11 mg upper limit; names manganese superoxide dismutase, arginase and pyruvate carboxylase as manganese-dependent enzymes; lists food sources; says deficiency is very rare and no groups are known to be at risk; says no trial has tested manganese alone for bone and human trials for diabetes are lacking; describes toxicity from inhaled dust and contaminated water; and says manganese has no known clinically relevant medication interactions.