Anemia occurs when your blood doesn't have enough hemoglobin. Hemoglobin is a protein in your red blood cells that carries oxygen from your lungs to the rest of your body. All parts of your body need oxygen. Anemia can starve your body of the oxygen it needs to survive. Some people refer to anemia as "low blood".
So yes basically Anemia is the same as "low blood"
Please don't confuse "low iron" with anemia!! Low iron stores can lead to anemia but it is not automatic. I'm always severely iron deficient BUT I am not always anemic. My ferrtin scores typically run from as low as 3 to as "high" as 7. You are considered iron deficient once your ferritin dips below 10. Anemia is determined by your Hgl acore and your Hct. Hgl (hemoglobin is a measure of the oxygen carrying capacity of your blood) Acceptable scores for women run 12-15. Hct is a count of your red blood cell supply. I can't remember the normal range here but it is easy to look up online. Also please remember that there are many different forms of anemia. Iron deficienty is one of the most common forms but iron deficiency can and does occur without anemia.
I'm certainly no expert but I think I know a little bit about hair loss. I am in remission from an autoimmune form of anemia. As I understand it hair loss can occur after a sudden shock to the system, such as the severe drop in hemoglobin or other blood levels. My hair loss occurred about 3 months after I was diagnosed and started treatment. My hair fell out for a few days and then stopped as fast as it started. All the hair has now grown back and it's even the right colour (not grey!). I've also been told, this type of hair loss never results in baldness. Once the body's normal "rhythm" returns the hair starts growing again normally.
I've had lots and lots of explanations, including the corticosteroids (prednisone) as the cause of the problem. This however seems to make the most sense to me.
So long live thick, "non-grey" hair!
There are several different blood tests used in the US to look for iron deficiency. Ferritin level is the most common (and supposedly most reliable) It reflects your total iron stores. The number range used that is considered within range is 10-220 (some go a bit higher to almost 300, each lab is different but generally agree on the lower end) I can't remember the actual unit of measure used. Even though my iron levels are extremely low I don't have a big problem with hair loss. I've always had this issue so I think my body has just learned to compensate.