Ferritin is the primary intracellular iron storage protein and a useful indirect marker of total body iron stores. The laboratory reference range in most UK settings is 30 to 400 micrograms per litre for men and 13 to 150 micrograms per litre for women. This is an extraordinarily wide range. A man with ferritin of 30 and a man with ferritin of 400 both receive a normal result, but these represent very different iron stores with very different health implications.
The Problem at Both Extremes
At the low end, ferritin below 30 micrograms per litre is associated with iron depletion even if haemoglobin has not yet fallen into anaemic range. This pre-anaemic iron depletion produces fatigue, reduced exercise tolerance, poor cognitive function, hair loss, and impaired thyroid function. Many people with ferritin of 12, technically within the female normal range, experience significant symptoms that resolve with iron repletion. At the high end, ferritin above 200 in men and above 150 in women is associated with oxidative stress, insulin resistance, and increased risk of cardiovascular disease and liver disease. Ferritin is also an acute phase reactant, rising during inflammation, which can mask the true iron status picture.
The Functional Optimal Range
For most functional medicine practitioners and longevity-focused clinicians, optimal ferritin for adults seeking health and performance sits between 60 and 80 micrograms per litre for women, and between 70 and 120 micrograms per litre for men. These ranges support adequate iron supply for energy metabolism, cognitive function, and immune health, without the oxidative and metabolic burden of high iron stores.
Sources
- Milman, N. (2011). Serum ferritin in Danes: studies of iron status from infancy to old age. Acta Haematologica, 84(6), 272-279.
- Rajpathak, S.N., et al. (2009). The role of iron in type 2 diabetes in humans. Biochimica et Biophysica Acta, 1790(7), 671-681.
- Weinberg, E.D. (2008). Iron toxicity: new conditions continue to emerge. Redox Report, 14(2), 49-57.