Hi,
I posted my blood results on the ThyroidUK forum and they advised getting advice from here. I have an underactive thyroid and taking 215mg of Levothyroxine a day and all is fine in that respect. I've been told levels must be at optimum and mine are low
B12 241 (197-771) - was 215 three months ago and Folate 5.0 (3.9 - 25.0) - was 5.9
Any advice on how to self supplement will be most appreciated as my doctor said all is in range and no need for another check up until a years time.
on B12 - are you symptomatic of B12 deficiency - you say that things are fine in respect of thyroid which rather implies that you don't have any symptoms. In that case you are not B12 deficient and there is no need to supplement.
Serum B12 is a difficult test to interpret - it is an indirect measure of what is happening in cells and there is a huge variation in the normal range. This means that the test, if used as a single measure of B12 deficiency, will miss 25% of people who are deficeint, but will also pick up 5% who are.
Supplementing with high doses of B12 when you don't have a deficiency is at best a waste of money - and at worst could kick of a reaction which can leave you with high levels in your blood but not enough getting through to your cells (functional deficiency). This can be treated by getting levels even higher so enough B12 beats the reaction and gets into cells but this means you get trapped in needing to continually take very high levels of B12 to ensure you get enough ... and having high serum B12 makes getting a proper diagnosis of problems with B12 difficult.
There are some figures that I know get quoted often on the forum about levels being optimal at particular points but unfortunately these are being quoted out of context as they actually relate to people who have been treated for B12 absorption problems with injections and normal range for these people gets very skewed - in part because of the reaction I mentioned above.
The drop in your folate levels isn't significant and the difference is really within the range that you would be likely to get if you used the same sample several times. The results are in the normal range which doesn't have the sort of variation that you see with B12.
You can find a check list of symptoms of B12 here
Sally Pacholok and Dr Stuart consider B12 test levels are set too low, as does Professor David Smith, especially for people over 60 years of age.
Test results at any age should definitely not be taken in isolation - latest BMJ research advises that symptoms are paramount, especially when combined with autoimmune hypothyroidism - although many symptoms overlap, if there are neurological symptoms, possible malabsorption should be investigated and treated early.
This link posted by Dr John Midgley (Diogenes), scientist and adviser to HU TUK shows how Hashimoto's (HT) (often silent) may progress to gastric atrophy leading to impairment of the parietal cells and eventually PA.
low folate and low b12. Need advice
B12 217ng/L low folate/serum ferritin
Extremely low Folates but B12 through the roof. 
My B12 and folate. BetterYou Pure Energy B12
Treatment for low Vitamin B12 88ng/L and low serum folate 
