Iron and oxygen
Your body uses iron to make hemoglobin, the part of your red blood cells that carries oxygen. If hemoglobin falls, less oxygen reaches your muscles and brain. You can feel:
- tired and weak,
- short of breath on stairs or with exercise,
- foggy, with poor concentration,
- your heart beating faster or pounding.
Low iron before anemia
Your stored iron (ferritin) usually runs low first; hemoglobin drops later. Some people feel unwell while their hemoglobin is still "normal." That's why doctors often check ferritin as well as hemoglobin.
What to do
Tiredness has many causes. If you're always tired, ask your doctor whether checking your iron makes sense for you.