Manganese
Manganese is an essential constituent of several enzymes. It plays a number of roles:
- It contributes to the metabolism of proteins, fats, and carbohydrates.
- It participates in antioxidant activity to protect the body from cell damage.
- It contributes to bone health.
- It helps support immune function and the reproductive system.
- Together with vitamin K, it helps with blood coagulation and wound healing.
Sources
Nuts and seeds, legumes, various fruits and vegetables, cereal products, and some fish and seafood are good sources of manganese. It is also found in tea, coffee, and wine.
Approximate manganese content
| Food | Portion | Content |
|---|---|---|
| Wheat germ, toasted | 30 g | 6.0 mg |
| Blue mussels, steamed | 75 g | 5.2 mg |
| Pine nuts | 60 mL | 3.0 mg |
| 100% wheat bran cereal | 30 g | 2.0 mg |
| Hazelnuts, dry roasted | 60 mL | 1.7 mg |
| Wild blueberries, raw | 125 mL | 1.5 mg |
| Chickpeas, boiled | 175 mL | 1.3 mg |
| Amaranth,* cooked | 125 mL | 1.2 mg |
| Food | Portion | Content |
|---|---|---|
| Whole wheat spaghetti, cooked | 125 mL | 1.0 mg |
| Firm tofu, plain | 150 g | 0.9 mg |
| Maple syrup | 30 mL | 0.9 mg |
| Spinach, boiled | 125 mL | 0.8 mg |
| Bass, cooked | 75 g | 0.8 mg |
| Pineapple, raw, diced | 125 mL | 0.7 mg |
| Chocolate, 70% to 85% cocoa | 40 g | 0.7 mg |
*Amaranth is an ancient grain that has been cultivated for thousands of years.
Adequate intake (AI)
AI is the recommended average daily nutrient intake based on estimates of nutrient intake by groups of healthy people.
Manganese Requirements
| Age | Men | Women |
|---|---|---|
| 1-3 years old | 1.2 mg | 1.2 mg |
| 4-8 years old | 1.5 mg | 1.5 mg |
| 9-13 years old | 1.9 mg | 1.6 mg |
| 14-18 years old | 2.2 mg | 1.6 mg |
| Age | Men | Women |
|---|---|---|
| 19-50 years old | 2.3 mg | 1.8 mg |
| > 50 years old | 2.3 mg | 1.8 mg |
| Pregnancy | 2.0 mg | |
| Breastfeeding | 2.6 mg |
Only a small percentage of manganese is absorbed from food sources. Its absorption is slowed when consumed with foods high in calcium, phosphate, and fibre, but increases during iron deficiency.
Deficiency
Since manganese is present in many foods, deficiency is rare. High iron intake can reduce its absorption, as the two minerals compete with each other.
Manganese deficiency remains poorly documented in humans, but it is believed to cause the following symptoms:
- Nausea and vomiting
- Delayed growth in children
- Fragile bones and skeletal defects
- Rashes
- Abnormal metabolism of fat and carbohydrates
Toxicity
Toxicity is rare and not caused by diet. It can occur if a person inhales dust containing manganese or drinks water contaminated with unusually high levels of the mineral. Cases of probable manganese toxicity in individuals on chronic total parenteral nutrition (i.e., being fed intravenously with a nutrition solution) have also been reported.
Excess manganese results in the following:
- Decreased iron absorption
- Loss of appetite, headaches, and weakness
- Tremors and muscle spasms
- Mood swings, irritability, and depression
- Parkinson's-like symptoms (e.g., movement problems, loss of balance, confusion)
- Lung problems (e.g., cough, bronchitis, pneumonia)
Supplements
Since manganese is commonly found in the food we eat, supplements are not necessary.
Always watch your diet:
it has a strong impact on your health!© Copyright Vigilance Santé
The patient information leaflets are provided by Vigilance Santé Inc. This content is for information purposes only and does not in any manner whatsoever replace the opinion or advice of your health care professional. Always consult a health care professional before making a decision about your medication or treatment.