Manganese

BoneAntioxidant

Essential trace mineral for bone matrix, antioxidant defence, and blood sugar control. Most people get plenty from food — supplementation is rarely needed.

EvidenceLimited (general use)

Strong evidence for required intake. Limited evidence that supplementation benefits people who aren't deficient. Some bone-formula RCTs include manganese alongside calcium, K2, and others — the contribution of manganese specifically is hard to isolate.

Manganese is a cofactor for several enzymes including manganese superoxide dismutase (MnSOD, a major mitochondrial antioxidant), arginase (urea cycle), and the enzymes that build bone matrix and cartilage. Deficiency is genuinely rare — typical diets provide plenty — but it does happen on heavily-processed-food diets or with certain medications. The opposite end (manganese toxicity) is more of a concern: occupational exposure (welding) or contaminated well water can cause Parkinson-like neurological symptoms. For most people, this mineral lives quietly in a multivitamin and doesn't need its own attention.

Form
Manganese gluconate, sulfate, or bisglycinate — typically 2 mg per dose in multivitamins.
Dose
1.8–2.3 mg/day (RDA). Don't exceed 11 mg/day from all sources (upper limit). Standalone supplementation rarely needed.
Timing
With food. Often in multivitamins.
Schedule
Daily if supplementing.
Side effects
At reasonable doses, none. At high doses (especially via inhalation): neurological symptoms resembling Parkinson's, headache, irritability.
Interactions
Calcium, iron, magnesium compete for absorption. Antibiotics (quinolones, tetracyclines) — manganese reduces absorption; separate by 2 hours.
Contraindications
Liver disease (impaired clearance, accumulation risk). Manganese-related neurological symptoms (current or prior). Pre-existing Parkinson's (caution).
Lab markers
Whole-blood manganese (limited utility). MRI of basal ganglia in suspected toxicity. Symptom monitoring more useful than testing in most cases.
Food sources
Whole grains (especially brown rice, oats, whole wheat), nuts (almonds, hazelnuts, pecans), leafy greens, pineapple, beans, mussels, tea (high in manganese). Plant-heavy diets easily exceed RDA.

Pairs with

Calcium, magnesium, zinc, vitamin K2 in bone formulas. Iron and copper (other trace minerals — balance matters).