Daily dose

The recommended daily dose is 2 to 5 mg.

Properties

Involved in metabolism

Manganese is involved in the metabolism of lipids, proteins and carbohydrates. Manganese also enables the body to synthesise certain enzymes. For example, the enzyme superoxide dismutase requires manganese production to enable the body to defend itself against oxidation, oxidative stress and cellular ageing.

Insulin production

Manganese is involved in the synthesis of insulin, a hormone involved in the control of blood sugar levels after carbohydrate intake.

Maintenance of bone mineral mass

Manganese is also involved in the synthesis and renewal of bone tissue, thus preventing bone demineralisation and osteoporosis.

Indications

• Arthrosis
• Allergic conditions
• Tiredness
• Liver damage
• Neurological problems
• Diabetes
• Stunted growth
• Myocardial infarction
• Kidney failure
• Osteoporosis
• Ulcers
• Blood clotting
• Thyroid
• Immunity
• It appears to be essential for the correct synthesis of antibodies
• Reproduction: deficiency leads to reduced fertility

Deficiency of manganese

Manganese deficiency has rarely been associated with inadequate dietary intake.

Skin problems (scaly dermatitis) and hypercholesterolaemia (high blood cholesterol) are the clinical symptoms associated with manganese deficiency.

Excess of manganese

The toxicity of manganese comes mainly from a contaminated environment.

People who inhale manganese dust (mining, smelting, metallurgy) are at risk of central nervous system disorders similar to Parkinson's disease.

In addition, people with chronic liver disease, people who take dietary manganese supplements, and infants with cholestatic liver disease who also take supplements are at greater risk of excessive manganese intake.

Interactions with other nutrients

Calcium and phytates found in legumes, nuts and seeds, and whole grains would reduce manganese absorption.

In addition, low iron stores would lead to increased manganese absorption.

Chemical properties

The atomic symbol for manganese is Mn and its atomic number is 25.

Manganese has an atomic mass of 54.938044 u, it is a silver-white transition metal.

Manganese sulphate is the neutral ionic compound of manganese cation and sulphate anion. Its chemical formula is MnSO4.

It is a white powder that is very soluble in water and turns pinkish red when hydrated.

It is used in the production of batteries, fertilisers and manganese dioxide.

Nutrients that contain manganese

Common sources of manganese include cereals, seafood, pulses, vegetables and nuts.

Food - portions - amount (mg)

• Mussels - 100g = 6.8
• Hazelnut - 30g = 3.8
• Pumpkin seeds - 60g = 2.6
• Wheat bran muffin - 110g = 2.1
• Oats - 175g = 1.6
• Cooked brown rice - 100g = 1.1
• Multigrain breakfast cereal - 30g = 1.1
• Cooked lima beans - 90g = 1.1
• Cooked wholemeal pasta - 74g = 1.0
• Pineapple - 82g = 0.8
• Whole grain bread - 30g (1 slice) = 0,7
• Oysters - 100g = 0,7
• Tofu - 100g = 0.6
• Cooked fresh soya beans (edamame) - 95g = 0.5
• Cooked quinoa - 74g = 0.5
• Dark chocolate 60-70% cocoa - 30g = 0.4
• Raspberries - 65g = 0.4
• Raw spinach - 30g (1 cup) = 0.3