Manganese & Health

What is Manganese & What Does it Do?

“Manganese is a mineral element that is both nutritionally essential and potentially toxic.” (1)  It gets its name from the Greek word for magic!  

Outside the human body, manganese is used in creating metal alloys like steel.  Within the body, manganese has many different actions including: (2)

• Amino acid metabolism

• Cholesterol metabolism

• Glucose metabolism

• Carbohydrate metabolism

• Reducing oxidative stress especially in the mitochondria (1)

• Bone formation

• Reproduction

• Immune function

• Blood clotting through vitamin K pathways

With all of these functions, why don’t we hear more about this mineral?

Manganese Deficiency: 

Here we find the answer to the above quandary: manganese deficiency is exceedingly rare.  While we see manganese deficiency in other animal species, we don’t see it within humans enough to fully understand how it affects us. 

Signs and Symptoms of Manganese Deficiency:

“The very limited evidence in humans suggests that manganese deficiency might cause bone demineralization and poor growth in children; skin rashes, hair depigmentation, decreased serum cholesterol, and increased alkaline phosphatase activity in men; and altered mood and increased premenstrual pain in women. Manganese deficiency might also alter lipid and carbohydrate metabolism and cause abnormal glucose tolerance.” (2)

Since this deficiency is so rare, we don’t have enough information to establish risk factors for developing this deficiency.  With the exception of people receiving their nutrition through a feeding tube or IV when manganese isn’t added, we do not see any populations with increased risk for developing manganese deficiency or inadequacy. (1)

Where to Find Manganese: 

Manganese is found in many different foods including: 

• Greens

• Whole Grains

• Legumes

• Nuts and Seeds

• Herbs and spices

• Coffee

• Tea

• Shellfish

• Drinking water

Daily Intake:

Manganese is one of our essential nutrients that is more mysterious to us.  We have not been able to pinpoint a recommended daily intake to avoid deficiency, so an adequate intake (AI) has been established instead.  Just as a reminder, AI levels are determined by surveying healthy people and calculating their average intake. 

The AI for biological males is 2.3 mg daily, a bit higher than for biological females who have an AI of 1.8 mg due to differences in absorption and metabolism.  During pregnancy, the AI increases to 2.0 mg daily and is highest for those who are nursing at 2.6 mg daily.

Toxicity:

Manganese is a mineral that can cause toxicity.  This most often occurs through inhalation in industrial settings or through water contaminated by industrial runoff containing high levels of manganese.  Manganese toxicity presents with neurological issues and in some cases with liver dysfunction. (1)  These symptoms occur due to accumulation of manganese in the brain and liver and include:  (2)

• Mania

• Insomnia

• Depression

• Delusions

• Anorexia

• Headaches

• Irritability

• lower extremity weakness

• changes in mood and short-term memory

• altered reaction times

• reduced hand-eye coordination

Those at increased risk of manganese toxicity include: (1)

• Individuals with an inherited manganese-overload disorder caused by mutations in the SLC20A10 or SLC39A14 genes.

• Those who inhale manganese dust (welders, smelters, miners)

• Those taking high doses of manganese supplements over long periods of time (years)

• Those on total parenteral nutrition

• Those with chronic liver disease

• Infants and children

• Those with iron deficiency

• Those who use ephedrone

Due to these toxic effects, an upper limit (UL) for manganese ingestion has been set at 11 mg daily for adults. (2)

Prevention and Treatment of Disease:

We do not have enough information to know if manganese supplementation can prevent or treat disease.  However, there is evidence that inadequate levels of manganese in blood or tissues is associated with several diseases including osteoporosis, diabetes, and epilepsy. (1)

Medication and Nutrient Interactions:

At this time, there are no known medications or nutrients that interfere with manganese or that manganese interferes with. 

Applications:

Our takeaways this week are: 

1. Manganese is another essential nutrient involved in many biological processes.

2. Manganese deficiency is very rare.

3. Manganese toxicity is more of an issue, but this is most often due to contaminated water or inhalation of manganese dust.

4. Currently, there isn’t enough evidence to support the use of manganese supplementation in the treatment of or prevention of disease.

5. Manganese is found in a variety of foods.

Next week: 

Next week we will investigate molybdenum.  Don’t worry if this nutrient is new to you like manganese was, I will do my best to help you understand molybdenum and when/if it might concern you. 

To our health!

References:

1. Higdon, J, “Manganese” Linus Pauling Institute, 2001; last update: 2021; accessed January 12, 2022; https://lpi.oregonstate.edu/mic/minerals/manganese

2. National Institutes of Health,  “Manganese - Fact Sheet for Health Professionals” Updated March 29, 2021; accessed January 12, 2022.  https://ods.od.nih.gov/factsheets/manganese-HealthProfessional/