Manganese

What It Is

Manganese is a trace mineral that the body requires in very small amounts but is essential for multiple biological processes. It occurs naturally in many foods and in the environment and is stored primarily in the bones, liver, kidneys, and pancreas. As a micronutrient, manganese functions mainly as a cofactor — a helper molecule that activates various enzymes involved in metabolism and antioxidant defense.

Dietary sources of manganese include whole grains, nuts, seeds, leafy green vegetables, tea, and legumes. Because only a small percentage of dietary manganese is absorbed (around 3–5%), maintaining adequate intake depends on consistent consumption of manganese-containing foods.

How It Works

Manganese plays a central role in numerous biochemical pathways by activating enzymes such as manganese superoxide dismutase (MnSOD), arginase, and pyruvate carboxylase.

1. Antioxidant defense: MnSOD is a critical mitochondrial enzyme that protects cells from oxidative stress by neutralizing superoxide radicals, harmful byproducts of cellular respiration. This action helps preserve cellular integrity and function.
2. Metabolism: Manganese-dependent enzymes facilitate the metabolism of carbohydrates, amino acids, and cholesterol, contributing to efficient energy production and synthesis of key biological molecules.
3. Bone formation: Manganese supports the synthesis of proteoglycans—structural components of bone and cartilage—working in concert with calcium, phosphorus, and vitamin D to promote skeletal health.
4. Wound healing and reproduction: Manganese is required for collagen formation and reproductive hormone synthesis, processes vital for tissue repair and reproductive health.

Why It’s Important

Manganese is essential for maintaining overall metabolic balance, growth, and defense against cellular damage. Adequate levels contribute to:

• Healthy bone structure and development, particularly during growth and aging.
• Proper brain and nervous system function, as manganese participates in neurotransmitter synthesis.
• Reduced oxidative damage, lowering the risk of chronic diseases linked to free radical stress such as cardiovascular disease or certain neurodegenerative conditions.
• Effective metabolism, ensuring that the body efficiently converts nutrients into energy and structural molecules.

Although deficiency is rare, it can lead to impaired growth, skeletal abnormalities, altered carbohydrate and lipid metabolism, and reduced fertility. Conversely, manganese is indispensable in small amounts but potentially toxic in excess.

Considerations

While manganese is essential, balance is crucial, as both deficiency and overexposure can cause health issues.

• Deficiency: Uncommon in humans but may occur in cases of malnutrition, malabsorption syndromes, or restrictive diets. Symptoms can include bone demineralization, poor growth, skin changes, and impaired glucose tolerance.
• Toxicity: More likely to occur from environmental or occupational exposure (e.g., inhalation of manganese dust in welding or mining) than from diet. Chronic overexposure can lead to neurological effects resembling Parkinson’s disease, known as manganism, characterized by tremors, gait disturbances, and mood changes.
• Absorption and interactions: Manganese absorption can be affected by other minerals — high intake of iron, calcium, or phosphorus can inhibit its absorption, while low iron levels may increase manganese uptake, potentially elevating blood concentrations.
• Supplementation caution: For most individuals, dietary intake is sufficient; supplementation is rarely necessary and should be guided by a healthcare provider to avoid toxicity.