Unsure of normal ranges for T4 and T3, any help would be massively appreciated.

[Sharkette8]

So I just phoned my surgery and my T4 level is 1.8 and my T3 is 11.6

Does this sound right or does it need to be lower. I am currently having some difficulty with weight loss and would like to know if my thyroid function is interfering with this?

[SlowDragon Administrator]

All labs have different ranges. Getting results over the phone is unreliable....mistakes happen

Eg FT3 result looks odd

Are you diagnosed as having thyroid problem?

The best way to get access to current and historic blood test results is to register for online access to your medical record and blood test results

UK GP practices are supposed to offer everyone online access for blood test results. Ring and ask if this is available and apply to do so if possible, if it is you may need "enhanced access" to see blood results.

In reality many GP surgeries do not have blood test results online yet

Alternatively ring receptionist and request printed copies of results. Allow couple of days and then go and pick up.

Important to see exactly what has been tested and equally important what hasn’t been tested yet

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies

Ask GP to test vitamin levels

You may need to get full Thyroid testing privately as NHS refuses to test TG antibodies if TPO antibodies are negative

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

Come back with new post once you get results and ranges

[Sharkette8 in reply to SlowDragon]

This is really useful. Appreciate this. Thank you.

[Sharkette8 in reply to SlowDragon]

I had a B12 test done recently which showed my levels at 78. Following this I have had a B12 loading (6 injections in 2 weeks). The next injection is 22nd of May and every 12 weeks following this.

[SlowDragon Administrator in reply to Sharkette8]

Ok

Low B12 is EXTREMELY common when hypothyroid

Were you diagnosed as having pernicious anaemia?

Or cause of low B12 unknown?

Some people need B12 injections more frequently than every 12 weeks. See how you get on

Are you vegetarian or vegan?

Are you on levothyroxine?

[Sharkette8 in reply to SlowDragon]

I am on Levothyroxine (125 mg)

My Pernicious Anaemia test came back negative. But I am a vegetarian (almost vegan, barring cheese and not a massive amount of it in my diet.)

[SlowDragon Administrator in reply to Sharkette8]

How long as vegetarian?

As a thyroid patient and vegetarian did you not regularly supplement?

Absolutely essential to regularly test vitamin D, folate, ferritin

What supplements do you take?

Getting full thyroid and vitamin testing recommended as since starting B12 injections levels are likely changed

Presumably you have Hashimoto’s?

Are you on strictly gluten free diet?

[Sharkette8 in reply to SlowDragon]

Vegetarian since birth. I am 30 now and only just been diagnosed as B12 deficient 2 weeks ago. I am not on a gluten free diet and not on any supplements either. I suspected I had hashimotos when I was first diagnosed in 2009 and the antibodies came back abnormal but no doctor ever gave any more information barring the prescription. SO I can't confirm if I have hashimoto's or not. I have requested a physical copy of my last full blood panel from my surgery which would be available tomorrow.

[SlowDragon Administrator in reply to Sharkette8]

If you had high thyroid antibodies then yes this confirms autoimmune thyroid disease aka Hashimoto’s

Astonishing as a vegetarian that you have never taken any B12 supplements

academic.oup.com/nutritionr...

The present review of the literature regarding B12 status among vegetarians shows that the rates of B12 depletion and deficiency are high. It is, therefore, recommended that health professionals alert vegetarians about the risk of developing subnormal B12 status. Vegetarians should also take preventive measures to ensure adequate intake of this vitamin, including the regular intake of B12 supplements to prevent deficiency. Considering the low absorption rate of B12 from supplements, a dose of at least 250 μg should be ingested for the best results.3

Strongly recommend getting full private testing

Iron and ferritin are frequently low too on vegetarian diet

[Sharkette8 in reply to SlowDragon]

Thank you so much for this. I am going to get myself booked in. I just feel so hopeless and hate when people dont give full information. I only accidentally ended up getting this information about this page from someone today otherwise I would have kept going with just trusting the receptionist at the surgery that my levels were 'normal', not knowing that there are things that they havent even tested for.

[SlowDragon Administrator in reply to Sharkette8]

For levothyroxine to work well we need optimal vitamin levels

Vitamin D at least over 80nmol

Folate at least over ten

B12 at least over 500

Ferritin at least half way through range (normally minimum of 70)

Anyone with hashimoto’s almost always has very poor vitamin levels

Obviously a vegetarian diet makes this significantly more difficult

Always test at least annually, ideally twice year if supplementing

ncbi.nlm.nih.gov/pubmed/286...

Vitamin D deficiency is frequent in Hashimoto's thyroiditis and treatment of patients with this condition with Vitamin D may slow down the course of development of hypothyroidism and also decrease cardiovascular risks in these patients. Vitamin D measurement and replacement may be critical in these patients.

endocrine-abstracts.org/ea/...

Evidence of a link between increased level of antithyroid antibodies in hypothyroid patients with HT and 25OHD3 deficiency may suggest that this group is particularly prone to the vitamin D deficiency and can benefit from its alignment.

ncbi.nlm.nih.gov/pubmed/186...

There is a high (approx 40%) prevalence of B12 deficiency in hypothyroid patients. Traditional symptoms are not a good guide to determining presence of B12 deficiency. Screening for vitamin B12 levels should be undertaken in all hypothyroid patients, irrespective of their thyroid antibody status. Replacement of B12 leads to improvement in symptoms

Folate supplements can help lower homocysteine

ncbi.nlm.nih.gov/pmc/articl...

Levothyroxine can decrease serum homocysteine level partly; still its combination with folic acid empowers the effect. Combination therapy declines serum homocysteine level more successfully.

Low ferritin frequent in hypothyroidism

endocrineweb.com/profession...

Iron and ferritin are complex if ferritin is low GP needs to do full iron panel test for anaemia

Come back with new post once you get full test results and ranges

[Sharkette8 in reply to SlowDragon]

Cheers thank you! I'll get on the case straight away.

[SlowDragon Administrator in reply to Sharkette8]

Get coeliac blood test too before trying strictly gluten free diet