As background, this all started in infancy. He had food intolerances with bloody stools, became anemic then but even after test after test failed to show any blood in his stool and we were supplementing with more and more and more iron he was still anemic. Finally when he was about 2 his hemoglobin was normal and his iron stores had finally gotten barely into a normal level. The GI we were working with had worked him up for everything you can check short of a colonoscopy, which he felt was too invasive and unlikely to show us anything useful. His advice was leave him alone- he's probably going to be fine.
When he was 4 we did another blood test and he was anemic again. I can't recall if that was the first time we had checked him since we had decided he was okay. I know there were at least a few tests done to see if he dropped back down after he got to the normal range and he seemed to hold steady for a time. But anyway, at 4 he was anemic again, although only very slightly. 2 months on a multivit + juice plus had him back to the normal range. Since then we've been spotty with the multi and slighly less spotty with the JP. He doesn't do well with daily supplements - gets bored of them quickly. And aside from that I am of the opinion that a multi shouldn't be necessary and if it is there is something else going on.
So last week I asked the pedi to recheck his iron. He's been exceptionally grouchy, prone to tantrums especially at meal and bedtimes lately and his hands are always freezing. His hemoglobin was 11.1 (normal range 11.5-15.5) so not terrible but not normal.
We're going back to the GI but I expect they will again find nothing. We see no indication of blood in the stools and have tested several times. He's a meet eater. Doesn't eat fruits and veggies to my preference but certainly his diet better than most kids his age I would think. Basically none of the typical reasons are true for him. So I'm looking for the atypical reasons - things your standard MD or GI wouldn't think of (malabsorption most likely, but why?)
As an aside, which may or may not be related, we found out of the same day that my 3 yr old DD is also anemic but I'm more suspicious of blood loss through the GI track with her - she is still very milk and soy intolerant and has had visible blood in her underwear once recently which is why we checked her iron. And she also is a hard one to get to eat. So the common risk factors are more at play in her case.