Thyroid UK

Blood Tests

Hi all recently had bood tests done was told by endo to alternate levo 50 one day 75 the next tried it for 8 weeks but felt really ill so i carried on with 75 per day my TSH has stayed the same 0.04 heres my blood test results TSH 0.04,T3 4.2 pmol/l T4 15.7 pmol/l B12 320ng/l. my chorlestral is still at 7.5 have tried for ages to get it down through diet cant take statins as will make my fibro worse they are going to send me to Lipids docter could have Familial Hypercholesterolaemia dad died of heart attack mum has angina just something else added to everything else wrong with me x

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When you give your blood tests it is helpful if you can also get the ranges too, as labs differ throughout the country and it makes it easier for members to comment.

The most important question is 'how do you feel' on 75mcg per day? Doctors/Endos have no reason to adjust your thyroid meds due only to the TSH. Your TSH, to me, seems fine. Dr Toft says some need a very low or even suppressed TSH to feel well.

Where you diagnosed as Fibroymyalgia or hypothyroid?

Your B12 is too low and should be at least 500 or above. You can get methylcobalamin B12 from Amazon and this is the link:-

You can also get them from health shops but I have found Amazon cheaper and it must be methylcobalamin and not cyanocobalamin. You cannot overdose on B12 as excess is excreted through urine.

Usually, when on optimum thyroid gland medication our cholesterol levels fall.


I have read that its not the actual Cholesterol that provokes a heart attack/disease but the the high homocysteine levels within. Vitamin B12 deficiency raises homocysteine.


Vitamin B12 deficiency

Serum homocysteine and methylmalonic acid levels are considered more reliable indicators of B12 deficiency than the concentration of B12 in blood.[35] The levels of these substances are high in B12 deficiency and can be helpful if the diagnosis is unclear. Approximately 10% of patients with vitamin B12 levels between 200–400pg/l will have a vitamin B12 deficiency on the basis of elevated levels of homocysteine and methylmalonic acid.Vitamin B12 deficiency causes particular changes to the metabolism of 2 clinically relevant substances in humans:

Homocysteine (homocysteine to methionine, catalysed by methionine synthase) leading to hyperhomocysteinemia;



When it accumulates, homocysteine is toxic to the cardiovascular and nervous systems. It has been proven to increase the risk of coronary heart disease and increase the levels of low-density lipoprotein (LDL or “bad” cholesterol).

Hope this helps

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