Iron is important because an iron level that is too high or too low can cause fatigue, poor immune function, cold intolerance, decreased thyroid function, and poor memory. Chronic fatigue patients should have their iron level and total iron binding capacity (TIBC) checked. Although not useful by themselves, dividing the iron level by the TIBC gives you a percent saturation, which is a useful measure and which should be at least 22%. In addition, they have their ferritin blood level checked, which should be over 40. These three tests all measure iron status. Even if a person's iron percent saturation is low but still normal, that person will often feel fatigued, despite not being anemic. The ferritin level, however, will pick up subtle deficiencies. Unfortunately, even minimal inflammation will falsely elevate the ferritin measurement and make it appear to be falsely normal. This is why all three tests are necessary to determine iron deficiency.
One study reported in the British medical journal Lancet showed that infertile females whose ferritin levels were between 20 and 40 — a ferritin level over 9 is technically normal — were often able to become pregnant when they took supplemental iron. Treating those with fatigue or restless leg syndrome whose ferritin levels were under 60 also resulted in improvement. Other research shows that low-normal iron levels cause poor mental functioning and poor immune function. This suggests that levels considered sufficient to prevent anemia are often inadequate for other body functions. Because too much iron can be very toxic, you should take a multivitamin without iron unless your blood tests show that you are low (using my normal ranges — not the labs!) in that mineral. Although iron is important, it is also pro-oxidative (that is, it promotes free radical activity) and can cause inflammation, arthritis, and liver and heart disease if the level is too high. This helps remind us that more is not always better.
Iron deficiency also contributes to hair loss and women with hair loss should aim to raise the ferritin level to between 50 and 100 ng/ml.
Iron supplements are not a cure for baldness. But as part of a multipronged approach, optimizing iron levels can be a big help.
It is normal for iron to cause constipation and a black stool. A bleeding ulcer can also cause black stool, but this is usually very foul smelling. Fortunately, if you take the iron every other day you get almost as much benefit as taking it daily — with fewer side effects. I aim to get the ferritin blood level over 60.