Manganese (Mn) is a mineral necessary in very tiny (trace) amounts for human health. In large quantities, manganese is poisonous. Manganese is used in some enzyme reactions and for the proper development of bones and cartilage. Humans must meet their needs for manganese from their diet. Manganese is found mainly in plants and in small quantities in some drinking water.



Adequate intake(mg/day)

Tolerable upper intake level (mg)

Children 0-6 mos.


Not established

Children 7-12 mos.


Not established

Children 1-3 yrs.



Children 4-8 yrs.



Boys 9-13 yrs.



Girls 9-13 yrs.



Boys 14-18 yrs.



Girls 14-18 yrs.



Men 19≥ yrs.



Women 19≥ yrs.



Pregnant women 18≤ yrs.



Pregnant women 19≥ yrs.



Breastfeeding women 18≤ yrs.



Breastfeeding women 19≥ yrs.




Manganese (mg)

Oat bran, 1 cup, cooked


Pineapple, raw, 1 cup


Pecans, 1 oz. (20 halves)


Chickpeas, ½ cup


Instant oatmeal, 1 packet


Walnuts, 1 oz. (14 halves)


Brown rice, cooked, ½ cup


Spinach, cooked, ½ cup


Sweet potato, baked


Blackberries, ½ cup


Refried beans, ½ cup


Raspberries, ½ cup


Black beans, ½ cup


Strawberries, ½ cup


AI = Adequate intake

mg = milligram

SOURCE: Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington DC: U.S. National Academies Press, 2001. (accessed April 2, 2018).


Researchers understand less about how manganese functions in the body than they do about many other minerals. Studies have shown that manganese is necessary for proper development of healthy bones and cartilage in animals. It is highly likely that manganese plays the same role in the development of human bones and connective tissue, although manganese deficiency is so rare in humans (and putting people on a prolonged manganese-free diet would be an unethical experiment) that this has not been proven experimentally.

Manganese is also necessary for the formation of an antioxidant enzyme in cellular mitochondria. Mitochondria, sometimes called the cell's power plant, are organelles that use large amounts of oxygen to produce energy. The production of energy by the mitochondria results in the formation of free radicals. Free radicals are molecules that cause damage by reacting with fats and proteins in cell membranes and in genetic material. This process is called oxidation. Antioxidants are compounds that attach themselves to free radicals so that it is impossible for free radicals to react with, or oxidize, other molecules. In this way, antioxidants protect cells from damage. Although manganese is not by itself an antioxidant, it is a necessary part of the enzyme reaction that neutralizes free radicals produced by mitochondria. Manganese is also needed in some enzyme reactions that allow the body to process the use of amino acids, cholesterol, and carbohydrates in the body.


Manganese is acquired through diet. It is not evenly distributed in the body but is concentrated in the bones, liver, pancreas, and brain. Excess manganese is removed in bile, a digestive fluid made by the liver. The role of manganese in health is not well understood. Both manganese deficiency and manganese excess are rare. The few cases of dietary manganese excess that have been recorded have resulted from accidental exposure such as from drinking water contaminated with manganese-containing industrial waste. The United States Environmental Protection Agency (EPA) recommends a concentration of manganese no higher than.05 mg/L in drinking water. Side effects of high levels of manganese include loss of appetite, headaches, tremors, convulsions, and mental changes such as hallucinations. If manganese is inhaled in dust or vapor, it can cause severe damage to the nervous system. Some miners and industrial workers are at risk of being exposed to airborne manganese.

Normal manganese requirements

The United States Institute of Medicine (IOM) of the National Academy of Sciences has developed values called Dietary Reference Intakes (DRIs) for many vitamins and minerals. The DRIs consist of three sets of numbers. The Recommended Dietary Allowance (RDA) defines the average daily amount of the nutrient needed to meet the health needs of 97%–98% of the population. The Adequate Intake (AI) is an estimate set when there is not enough information to determine an RDA. The Tolerable Upper Intake Level (UL) is the average maximum amount that can be taken daily without risking negative side effects. The DRIs are calculated for children, adult men, adult women, pregnant women, and breastfeeding women.

The IOM has not set RDAs for manganese because not enough information is available about the need for manganese in humans. Instead, it has set AI levels for all age groups. Because high levels of manganese affect the nervous system, the ULs are very conservative. Some experts point out that vegans and vegetarians who eat large quantities of whole grains routinely take in manganese in amounts well above the established UL without any obvious adverse effects. AIs and ULs for manganese are measured in milligrams (mg).

The following list gives the daily AIs and ULs for manganese for healthy individuals as established by the IOM.

Sources of manganese
Alternative medicine—
A system of healing that rejects conventional, pharmaceutical-based medicine and replaces it with the use of dietary supplements and therapies such as herbs, vitamins, minerals, massage, and cleansing diets. Alternative medicine includes well-established treatment systems such as homeopathy, Traditional Chinese Medicine, and Ayurvedic medicine, as well as more recent, faddriven treatments.
Amino acid—
Molecules that are the basic building blocks of proteins.
A molecule that prevents oxidation. In the body antioxidants attach to other molecules called free radicals and prevent the free radicals from causing damage to cell walls, DNA, and other parts of the cell.
A greenish-yellow digestive fluid produced by the liver and stored in the gallbladder. It is released into the intestine where it helps digest fat, and then is removed from the body in feces.
Conventional medicine—
Mainstream or Western pharmaceutical-based medicine practiced by medical doctors, doctors of osteopathy, and other licensed healthcare professionals.
Dietary supplement—
A product, such as a vitamin, mineral, herb, amino acid, or enzyme, that is intended to be consumed in addition to an individual's diet with the expectation that it will improve health.
A protein that changes the rate of a chemical reaction within the body without being depleted in the reaction.
Free radical—
A molecule with an unpaired electron that has a strong tendency to react with other molecules in DNA (genetic material), proteins, and lipids (fats), resulting in damage to cells. Free radicals are neutralized by antioxidants.
A simple sugar that results from the breakdown of carbohydrates. Glucose circulates in the blood and is the main source of energy for the body.
The complex set of regulatory mechanisms that works to keep the body at optimal physiological and chemical stability in order for cellular reactions to occur.
A chemical messenger that is produced by one type of cell and travels through the bloodstream to change the metabolism of a different type of cell.
An inorganic substance found in the earth that is necessary in small quantities for the body to maintain health. Examples: zinc, copper, iron.
A condition found in older individuals in which bones decrease in density and become fragile and more likely to break. It can be caused by lack of vitamin D and/or calcium in the diet.
The clear fluid part of the blood that remains after clotting. Serum contains no blood cells or clotting proteins, but does contain electrolytes.

The following list gives the approximate manganese content for some common foods:

Controversial health claims for manganese

Manganese supplements have not been proven effective in treating or preventing any specific disease or condition. However, based on a small number of laboratory and animal studies, practitioners of alternative medicine sometimes recommend supplemental manganese for the following conditions. These uses are considered speculative by practitioners of conventional medicine.



Liver damage may reduce the rate at which magnesium is removed from the body. People with liver damage (e.g., cirrhosis) may be at higher risk of developing symptoms of manganese excess.


Antacids and laxatives that contain magnesium (e.g., milk of magnesia) may reduce the amount of manganese absorbed from food.


No complications are expected from manganese acquired through food and water. Individuals who take multivitamin/mineral supplements containing manganese are unlikely to have any adverse effects. People who take manganese or joint supplements should be alert to how much manganese they are consuming, although overdose is extremely rare.

Parental concerns

Parents should have few concerns about children getting either too much or too little manganese. Supplemental manganese should rarely be necessary. Parents should encourage their children to eat a diet high in fruits, vegetables, and whole grains.

See also Artificial preservatives ; Flaxseed ; Whole grains .



Lieberman, Shari, and Nancy Bruning. The Real Vitamin and Mineral Book: The Definitive Guide to Designing Your Personal Supplement Program. 4th ed. New York: Avery, 2007.


American Academy of Family Physicians. “Vitamins and Minerals: How to Get What You Need.” Family . (accessed April 11, 2018).

Higdon, Jane, and Victoria J. Drake. “Manganese.” Linus Pauling Institute, Oregon State University. (accessed April 11, 2018).

MedlinePlus. “Manganese.” U.S. National Library of Medicine, National Institutes of Health. (accessed April 11, 2018).

Sarubin-Fragakis, Allison, and Cynthia A. Thomas. The Health Professional's Guide to Popular Dietary Supplements. 3rd ed. Chicago: Academy of Nutrition and Dietetics, 2007.

U.S. Department of Agriculture, National Agricultural Library. “DRI Tables and Application Reports.” Food and Nutrition Information Center. (accessed March 15, 2018).


Academy of Nutrition and Dietetics, 120 South Riverside Plz., Ste. 2000, Chicago, IL, 60606-6995, (312) 899-0040, (800) 877-1600,, .

Food and Nutrition Information Center, National Agricultural Library, 10301 Baltimore Ave., Rm. 105, Beltsville, MD, 20705, (301) 504-5414, Fax: (301) 504-6409,, .

Institute of Medicine, National Academy of Sciences, 500 Fifth St. NW, Washington, DC, 20001, (202) 334-2352,, .

U.S. Food and Drug Administration, 10903 New Hampshire Ave., Silver Spring, MD, 20993-0002, (888) INFO-FDA (463-6332), .

Helen M. Davidson

  This information is not a tool for self-diagnosis or a substitute for professional care.