Iron
Ferritin
What This Marker Tells Us
Measures your body's iron storage levels, acting as a reservoir that releases iron when needed for red blood cell production, energy metabolism, and cellular function throughout your body.
Why It Matters
Ferritin is the most sensitive early indicator of iron status, often changing before other iron markers or symptoms appear. Low ferritin reveals depleted iron stores that can cause fatigue, hair loss, restless legs, difficulty concentrating, and reduced athletic performance even when hemoglobin remains normal. Women of reproductive age are particularly vulnerable to low ferritin due to menstrual losses. However, ferritin is also an acute phase reactant, meaning it rises with inflammation, infection, liver disease, or metabolic syndrome, sometimes masking true iron deficiency. Optimal ferritin levels support thyroid hormone conversion, neurotransmitter production, immune function, and cellular energy production, making this marker foundational for vitality and performance.
How to Interpret Your Trends
Low ferritin (below 30 ng/mL for women, below 40 ng/mL for men) indicates depleted iron stores requiring repletion, even if anemia hasn't developed. Symptoms often improve dramatically with optimization. Typical ferritin (30-100 ng/mL for women, 40-150 ng/mL for men) suggests adequate reserves for most people. Higher optimal ranges (50-100 ng/mL) support athletic performance and cognitive function. High ferritin (above 150 ng/mL for women, above 300 ng/mL for men) may reflect inflammation, metabolic syndrome, liver disease, or true iron overload. Rising ferritin trends warrant investigation even within reference ranges, as persistently elevated levels correlate with increased disease risk.
What Influences This Marker
Ferritin depletes with menstrual blood loss, blood donation, internal bleeding, inadequate dietary iron, or malabsorption. Vegetarian and vegan diets often lead to lower levels due to less bioavailable non-heme iron. Intense endurance training increases iron demands. Ferritin rises with iron supplementation, inflammation, infection, alcohol consumption, metabolic syndrome, and liver conditions. Genetic hemochromatosis causes persistent elevation. Recent infection or injury can temporarily elevate ferritin independent of iron status.
How Your Team Uses It
Your coach evaluates ferritin in context with iron saturation, inflammation markers, and symptoms to distinguish true iron deficiency from inflammatory states. They'll develop targeted iron repletion protocols including dietary strategies, supplementation type and dosing, and co-factors like vitamin C to enhance absorption. For elevated ferritin, they'll investigate inflammatory causes, assess metabolic health, and determine if medical evaluation is warranted.
Related Signals We Also Review
Iron saturation, TIBC, serum iron, hemoglobin, MCV, hs-CRP, and comprehensive metabolic panel for complete iron and inflammation assessment.