I have underactive thyroid so first step whenever I am feeling fatigued is to get that tested - I know by now and gradually educating the GPs in my practice to check more than just TSH and T4, the thyroid levels are now all good.
however recently been feeling really fatigued - particularly after exercise. I have been dieting, and the weight loss has really slowed down. I am feeling pretty miserable as I am doing everything I should, lost over 2 stone so I know what I am doing food wise.
I got my blood tests back today and B12 is in the bottom quarter (570 in range 180-2000), ferritin is also in bottom quarter (5.4 in range 2.8-20) but both that dreaded word NORMAL.
I have received these results even whilst taking a high dose slow release vitamin b12 tablet. I have recently gone to a b12 spray which seemed to give me a boost the first day or so, but I did a long hike and the days after I am floored and quite low.
Does anyone have any ideas, surely taking b12 I would be higher in the range than I am now? I seem to be particularly tired if I do a bit more exercise, having lost the weight I felt able to do more and since doing that, I am just worn out especially the days after, I feel great the day of but not following. I am prepare to think its just depression but don't feel it really is that.
I also take zinc, selenium, magnesium, vitamin D. I am due to get vitamin D tested again in November they will only check it once a year.
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lumpymum
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There is a complex interaction between folic acid, vitamin B12 and iron. A deficiency of one may be "masked" by excess of another so the three must always be in balance.
Symptoms of a folate deficiency can include:
symptoms related to anaemia
reduced sense of taste
diarrhoea
numbness and tingling in the feet and hands
muscle weakness
depression
Folic acid works closely with vitamin B12 in making red blood cells and helps iron function properly in the body
Taking any form of B12 supplements beforehand will have "skewed" the test results making them meaningless.
Having Thyroid problems will put you at risk of having a B12 deficiency and some of the symptoms are similar.
Exhausting oneself if B12 or Folate deficient will take longer to recover.
I am not a medically trained person but I've had Pernicious Anaemia (a form of B12 deficiency) for more than 46 years.
Thank you. Yes folate was checked I’ve written the wrong word above. It was low quartile at 5.4 (2.8-20) the ferritin was 121 but didn’t catch the range think it was 15-200?
Interesting. I thought that in some countries the lower limit started at 500. I’m in the bottom 1/4 of the U.K. range, so didn’t know if I should aim for being higher within that range to achieve a feeling of wellness (reduction in symptoms) or if my normal would ordinarily be in the higher range?
No. That’s a common myth, especially on the thyroid forum. I do ish they would stop promulgating it. There was one paper published in Japan that said that the bottom of their range was 500. But there was no reference to back it up and no other sources. Unfortunately the authors of a popular book decided that it would boost their case if they spread such obvious nonsense.
Another Japanese paper said that more than 90% of normal people have values below 500. That is in keeping with other studies.
Strangely enough, most of those who think that you need blood levels over 500 are the same people who say that doctors should ignore blood levels and only look at symptoms.
I’m also achieving that level after taking 1000 mcg daily slow release b12 for about a year. I’d have thought my levels would be higher if I’m taking a supplant
Thank you so much, very informative. As I’ve asked it’s not PA then, and helped to rule out low b12 as source of my issues. I thought it was Europe that ranges start at 500 rather than japan.
Sounds like maybe folate wont be an issue either by using the same approach?
Could it be when I’m exercising I’m using up more of my stores and the low I’m getting is because I can’t replinish quickly enough using the rate you mention above?
Sorry to come with more questions, feel I need experience in this area which my gp may not have.
Yes thank you, just based on how I was with no b12 not sure I could cope for weeks without. Is that the only route to a true test rather than making an allowance for supplements?
Taking supplements that contain B12 will affect any tests ordered by your doctor to assess your B12 status. You should not take any supplement with B12 before having your B12 assessed (including MMA/homocysteine/Active B12).
For testing intrinsic factor antibodies: keep one week between an injection and the test".
You mention having TSH & FT4 tested - so how about FT 3 ? Maybe you are not converting well - what is your dose ? Also what are your levels of T4 & TSH ? - with ranges ...
Yes thank you I got these but not to hand. free t3, was mid range. Tsh was almost undetectable and t4 was higher end of the scale so we reduced my thyroxine. I tried to say about keeping yah suppressed was ok as long as t3 t4 ok but gp wasn’t having it.
So I ruled that out and looking at other factors for fatigue, depression, weight loss slowed and creeping into weight gain (even though I’m dieting and lost 2 stone already and doing nothing different other than more exercisebut not so much itsmassuve muscle gain!) thought b12 tablets were maybe just not working and need to go with spray but not sure this is of any use either now. Really don’t feel it’s just depression because of the change to metabolism and these elements.
When you have your thyroid test results with ranges you could post on Thyroid UK here on HU. Many of us are on both. I am thinking it is possible your T3 level is not optimal. Do you have Hashimotos ?
Most people feel better with a T3 nearer the top of the range. It's only when you post both the FT4 & FT3 that experienced members on Thyroid UK can see if you are converting well ...
Yep I’ve lost my readings but tsh was less that 0.5, t4 was 20ish (9-21) and free t3 was around 4ish (range 2.6-6.2). I was asked to reduce thyroxine by 25 at this point. I’m of the view I was probably ok at that but couldn’t find anything to argue with that and so we reviewed b12, folate, etc. I’m seeing gp on Monday so any ideas welcome. I’ll post this on the thyroid page also
You only need to reduce your dose if the T3 is over range. Docs are obsessed with TSH. Over on Thyroid UK you will be given links to support your appointment. I am away from home at the moment so unable to access links. Hope all goes well 😊
That’s my understanding but they caught me on the phone unprepared hence the appointment. Meanime dose reduced. But I was fatigued before that! Which is why I got tested. I’ll print Thyroid U.K. stuff off and see if I can take that along with me.
Supplementing with only zinc will deplete your copper. Copper deficiency much like b12- your zinc and copper have to be in ratio- look it up. Your Folate is low, you may not absorb folic acid well. Quite a lot of people cannot, having mthfr variants and need to supplement with 6s-5mthf.
Iron must be optimal not simply within range. Is your thyroid optimal or within range? Hypothyroidmim.com talks a lot about optimal levels and lot of folks do not do well with synthetic thyroid and can only get results using desiccated thyroid. Do not take any b12 supplements when getting tested, they will only skew your results. B12 pills and sprays are highly unlikely correct a b12 deficiency. b12-institute.nl/caution-no...
I had multiple typical symptoms of B12 deficiency including neurological symptoms with most of my B12 results between 300 - 500 ng/L.
It is possible to have functional B12 deficiency, where there is plenty of B12 in the blood but it's not getting to where it's needed in the cells.
UK article below, from BMJ, suggests that people who have the clinical signs of B12 deficiency should be treated even if B12 levels are in normal range.
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