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Iron is a fundamental mineral involved in numerous biological mechanisms, such as organs’ oxygenation and specific intracellular processes. Although little present at birth, intracellular iron concentration in the brain increases rapidly, supporting neurotransmitter synthesis, myelination, and synaptic plasticity. However, an overload of iron is toxic, as it is involved in oxidative stress and inflammation, which, in turn, cause cells to deteriorate. Such an increase of brain iron has been shown not only in neurodegenerative diseases but also in normal aging, notably in the basal ganglia. Neuroimaging methods allowing iron quantification in vivo are quite recent. As a result, studies on this topic are limited, but still offer the possibility to draw up a preliminary report of the effects of age-related iron overload on brain integrity and motor and cognitive performance. In normal aging, increased levels of brain iron have been related to atrophy, disrupted neural activity, and motor and cognitive deficits, pointing to the deleterious effects of higher iron concentration on brain integrity and motor and cognitive performance. Factors that modulate brain iron concentration, such as genetic, physiological, and lifestyle-related factors, have been very little studied as well. Identifying these factors, notably the modifiable ones, would allow us to define recommendations promoting brain health and prevent neurodegeneration triggered by iron-induced oxidative stress and inflammation.