Yet another "too much isn't good for you" story - with particular relevance to anyone taking folic acid and (maybe) folates.
High folic acid intake in aged mice causes a lowered immune response
Date:
January 11, 2016
Source:
Tufts University, Health Sciences Campus
Summary:
A study in aged mice shows that excess folic acid intake causes lowered immune function because important immune cells, called natural killer cells, are less effective. These results build upon the findings of a previous study in 2005 by the same lab that found that 78 percent of healthy postmenopausal women had unmetabolized folic acid in their blood plasma, which is indicative of excess folic acid intake.
This is a difficult situation as poses the question whether to supplement folic acid or not ? ? ..
Low thyroid hormone and failing adrenals inhibits our ability to produce stomach acid so inhibiting all B12 and folic acid absorption. With a lack of nutrients the body slips into a deeper state of deficiency with the low stomach acid allowing yeast/parasite overgrowth inhibiting absorption further.
Folic acid also keeps homocysteine in check and an elevated level can cause cardiovascular disease and disrupt thyroid metabolism at the cellular level as it blocks T3 from binding with a helper enzyme.
But then unused folic acid (similar to thyroid hormones ) may not be easily detoxified from the body (especially those with MTHFR issues) so complicating problems further. It does not (necessarily ) take over supplementation to cause this problem but just the bodies inability to use it correctly.
Obviously our immune system is important and usually a little compromised in Hashi sufferers so it is a fine balance but in light of the above I would advocate supplementing folate (not folic acid )..
Disclaimer: I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.
I'm coming to this very late. I wanted to message you in private as I didn't want to hijack the posting but this doesn't appear to be possible. So, Helvella I apologise for asking the following within the context of your original post.
The problem I have is that while I have high B12 levels (621 range: 250-725 pmol/L), folate levels are right at the bottom of the range (10.9 range:10.4-42.4 nmol/L). If there was an absorbency problem surely the B12 would also be low? NB I have also had active B12 tested and that is in the upper level of the range. Interestingly my FT3 levels are in the bottom third of the range: 4.17 (3.1-6.8 pmol/L). NB I've never been diagnosed as hypo so not on medication as all other TFTs are in range and all other tests results are ok eg vit D, antibodies.
It seems a mystery to me - and a problem that hopefully will be taken seriously by my GP when I see her on Weds. Should I be asking for any tests in particular?
I've been trying to get through to the PA Society this morning and have left a message. I've also booked on to the B12 conference in June where speakers include Sally Pacholok, Dr Ashan Ahmad (talking about people who have in-range TFT but are symptomatic of hypothyroid) and Anne Pemberton, who is one of the practitioners mentioned in the website you've forwarded. Maybe at last I'm getting to the bottom of the situation - although I feel that I'll need to part with megabucks before all is finally revealed!
WOW ! - I am impressed ! I went last year to the B12 Conference - and as I live in Crete am not able to go again. Sally Pacholok spoke last year and is impressive. Do not be afraid to ask questions .....
The PAS will get back to you - they did to me when I needed help with my grandson.
So pleased you are taking positive action - that in itself can make you feel better !
Wishing you well and let me know how things go ....
I found this article very confusing. They seem to use the terms 'folic acid' and 'folate' interchangably, as if they were the same thing. They also talk about 'old' mice, and then go on to talk about pregnant women. Well, how many of these 'old' mice were pregnant? Doesn't seem to me as if much useful information has come out of this research.
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Blood results- T3 levels consistent? Can I improve them? 
What to push for next
Quick t4 & tsh question 
