Low ferritin usually means that the body’s iron stores are reduced. Ferritin is an important laboratory marker that reflects stored iron, so a low result can suggest declining iron reserves even before anemia develops. This becomes especially relevant when symptoms such as fatigue, reduced stamina, hair loss, poor concentration, or lower exercise tolerance are present. Common causes include heavy menstrual bleeding, inadequate iron intake, malabsorption, pregnancy, or hidden gastrointestinal blood loss. Ferritin should not be interpreted alone; it is best understood together with hemoglobin, serum iron, transferrin saturation, and the overall symptom pattern. The best strategy is not only to raise the number, but to understand why iron stores became depleted in the first place.