Manganese is a naturally occurring element and an essential mineral nutrient. It’s important for maintaining good health, though manganese can be toxic at high levels.

Manganese deficiency is rare but can happen, especially with certain medical conditions. Read on to learn what manganese does and what it means if you have a deficiency.

Manganese is important for several functions in your body.

Metabolism

Your body contains numerous proteins called enzymes. Enzymes help to speed up chemical reactions. Manganese is a necessary component of several important enzymes in your body that work to process carbohydrates, amino acids, and cholesterol.

Antioxidant properties

An antioxidant stops harmful free radicals from damaging your cells. A manganese-containing enzyme present in your cells is the main detoxifier of free radicals.

Bone health and development

Manganese is essential for enzymes that help form bone and cartilage.

Wound healing

Manganese is present in an enzyme that provides an amino acid called proline. Proline is necessary for the production of collagen in your skin cells. Collagen formation is essential to wound healing.

Since manganese is found in many foods within our daily diets, reports of manganese deficiency are rare.

A person that does have a deficiency in manganese could experience the following symptoms:

  • poor bone growth or skeletal defects
  • slow or impaired growth
  • low fertility
  • impaired glucose tolerance, a state between normal glucose maintenance and diabetes
  • abnormal metabolism of carbohydrate and fat

Manganese deficiency could be caused by not having enough manganese in your diet. However, according to the Institute of Medicine’s review of dietary micronutrients, a clinical deficiency in manganese due to diet has not been observed in otherwise healthy people.

People with the following conditions could be at risk of lower-than-ideal manganese levels:

Manganese levels in your blood can be evaluated using a simple blood test. In order to perform the test, your doctor will need to obtain a blood sample from a vein in your arm.

According to Mayo Clinic Laboratories, the normal reference range for manganese in adults is between 4.7 and 18.3 nanograms per milliliter (ng/mL). You should always use the reference ranges that are provided with your laboratory report when interpreting your results. Consult with your doctor if you have questions.

In manganese depletion studies, symptoms subsided when subjects were given manganese supplementation.

If you have a manganese deficiency, your doctor will likely prescribe manganese supplementation. They’ll also suggest that you try to include more manganese-rich foods in your diet.

According to the Linus Pauling Institute, the adequate daily intake for manganese is 2.3 milligrams per day in adult men and 1.8 milligrams per day in adult women.

The effects of manganese deficiency have not been well studied in humans.

However, manganese deficiency in animals has been found to cause skeletal defects such as:

  • curved spine
  • shorter and thicker limbs
  • enlarged joints

Additionally, pregnant animals that were deficient in manganese gave birth to offspring that had significant movement issues. These included a lack of coordination and stability.

Some examples of foods that are good sources of manganese include:

  • nuts, such as almonds and pecans
  • beans and legumes, such as lima and pinto beans
  • oatmeal and bran cereals
  • whole wheat bread
  • brown rice
  • leafy green vegetables, such as spinach
  • fruits, such as pineapple and acai
  • dark chocolate

Iron-rich foods or supplements have been shown to lower your absorption of manganese. Phosphorus and calcium may also decrease your retention of manganese, but at a lower amount compared with iron.

Despite being essential for many important bodily functions, manganese can be toxic in large amounts.

Inhaled manganese toxicity is an occupational hazard for some workers. This is especially true for welders and smelters who are exposed to dusts or aerosols that contain manganese.

Inhaled manganese can cause inflammation of the lungs. Symptoms might include cough and bronchitis. People have also experienced a toxic effect of manganese when levels in drinking water are too high.

Manganese can also have a neurotoxic effect in large amounts. Symptoms include psychological disturbances and a reduction in motor function.

Manganese is an essential nutrient necessary for many important bodily functions. Generally, most people are able to consume enough manganese through their regular diet.

If you’re concerned that you have a manganese deficiency or if you have a condition that puts you at risk for lower-than-optimal manganese levels, talk with your doctor about your concerns.