Anemia: A deficiency of red blood cells

Anemia is a deficiency of red blood cells or the hemoglobin molecules within them.  Anemia results in the decreased capability of the blood to bring oxygen molecules to tissues. 

This results in hypoxia where the body or parts of the body are deprived of oxygen.

The human body depends on oxygen to survive. You can experiment with this fact by holding your breath underwater.  Eventually you will have to come up for air.  Oxygen is used by the body for energy and blood brings oxygen to the tissues.  Eventually if no new oxygen enters the blood stream as is simulated in the breath-holding experiment, the oxygen stores in the blood will drop and less and less is delivered to the tissues.

Anemia

The component of the red blood cell that carries oxygen is called hemoglobin and is found in red blood cells.  It is capable of binding oxygen in the lungs and releasing it in tissues.  A vital piece of hemoglobin’s architecture is an iron atom.  Without this, hemoglobin cannot bind oxygen.

So with this background in mind, anemia can result from anything that impairs oxygen uptake by hemoglobin or its delivery to tissues.  Anemia can result from low iron in the body.  Low iron would mean fewer functional red blood cells to take up the oxygen.   If you are severely dehydrated, blood flows more slowly and this could cause anemia.  Anemia can result from problems breathing so the lungs pass less oxygen to the blood.  Anemia can result from a massive blood loss so there isn’t enough around to supply the tissues.  The causes of anemia are widely varied.

The end result of mild anemia is tiredness.  Severe anemia can result in tissue death and extreme drowsiness leading to coma.  Anemia is a serious condition and should be treated and monitored by a licensed physican.