Ferritin

Your body keeps a reserve of iron, mostly bound to a protein called ferritin. A ferritin blood test gives an idea of how full those iron stores are. Low levels can occur with heavy periods, pregnancy, some diets, blood loss or problems absorbing iron.

Low iron stores are one of the things doctors commonly check when someone has increased hair shedding. Your GP may test ferritin alongside a full blood count, thyroid function and other bloods, depending on your symptoms.

Do not start iron supplements without speaking to your GP or pharmacist first. Too much iron can be harmful, and supplements can hide the reason your levels were low in the first place, which is worth finding out.