How to tell if I have a T4 to T3 conversion problem?

[iriscandy]

I'm new here, was diagnosed with Hypo in summer 2015, currently on Levo 75mcg/day, tested T3 three times during the past 2 yrs:

Jan 2017 dosage: 50mcg/day

FT4 13(9-24pmol/L) FT3 4.6(3.5-6.5mol/L) TSH 5 (0.35-5mu/L)

May 2017 increased dosage: 75mcg/day

FT4 16.9(9-24pmol/L) FT3 4.5(3.5-6.5mol/L) TSH 0.96 (0.35-5mu/L)

Nov 2017 Private health check dosage: 75mcg/day

FT4 16.7(11.5-22.7pmol/L) FT3 4.82(3.5-6.5pmol/L) TSH 2.27(0.54-4.78 mIU/L)

my latest blood test this month only tested TSH and FT4 as my GP was reluctant to include FT3:

Feb 2018 dosage: 75mcg

FT4 16.5(9-24pmol/L) TSH 1.3(0.35-5mu/L)

I was feeling fine on 75mcg initially, but recently I start to feel the inflammation again （especially in the evening）. It seems that my FT3 is quite low, does that mean my thyroid might not be able to convert FT4 to FT3? or the dosage is not strong enough?

I heard that NHS would not prescribe T3 anymore. Is there any place I can buy it privately?

Any input would be helpful. Thank you.

[SlowDragon Administrator]

Do you have Hashimoto's also called autoimmune thyroid disease diagnosed by high thyroid antibodies?

Have you had vitamin D, folate, ferritin and B12 tested?

Low vitamin levels and Hashimoto's both impact conversion

Getting vitamin levels optimal is important

Essential to know if cause is Hashimoto's

For full Thyroid evaluation TSH, FT4, TT4, FT3 plus TPO and TG thyroid antibodies. Plus vitamin D, folate, ferritin and B12.

Essential to test thyroid antibodies plus vitamins

Private tests are available

thyroiduk.org.uk/tuk/testin...

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.

All thyroid tests should ideally be done as early as possible in morning and fasting and don't take Levo in the 24 hours prior to test. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)

[iriscandy in reply to SlowDragon]

Thanks for your reply. I've got Hashimoto, and on Nov 2017 my TGAb was 479.9 (0-115IU/ml) and TPOAb 523.3（0-34IU/ml）, they were 249.6 (0-60IU/ml) and 1300 (0-60IU/ml) when I was first diagnosed on May 2015.

Vitamin D:I've got my vitamin D tested on May 2017: 50 (75-200nmol/L), so my GP recommended me to take 500 IU/day, which might not be enough?

ferritin: my ferritin was quite low a year ago as I had anaemia and heavy period, but after I take iron tablets everyday and Tranexamic during period, now it's back to 134 on Nov 2017 (115-150g/L)

folate: 14.2 on Jan 2017(2-17ug/L). As I'm preparing to get preganancy, I've been taken 400 ug per day for more than a year now.

B12: haven't tested it yet as my GP was reluctant to do more blood test, but I'm aware that it's related to anaemia, so currently taking liquid B12 everyday.

I'm also currently taking slenium and zinc tablet everyday.

I'll do a test to check my B12 level and thanks again for your tips.

[SlowDragon Administrator in reply to iriscandy]

According to Izabella Wentz the Thyroid Pharmacist approx 5% with Hashimoto's are coeliac, but over 80% find gluten free diet helps significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)

certainly very very many on here find strictly gluten free diet helps significantly

But don't be surprised that GP or endo never mention gut, gluten or low vitamins. Hashimoto's is very poorly understood

Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies

Ideally ask GP for coeliac blood test first

thyroidpharmacist.com/artic...

thyroidpharmacist.com/artic...

amymyersmd.com/2017/02/3-im...

chriskresser.com/the-gluten...

scdlifestyle.com/2014/08/th...

drknews.com/changing-your-d...

thyroidpharmacist.com/artic...

[greygoose]

Your conversion seems to be ok. You just need and increase in dose.

[Clutter]

Welcome to the forum, Iriscandy,

Your conversion was fine in May 2017 on 75mcg. FT3 was higher in Nov 2017 but that may be due to higher TSH flogging conversion.

As you're not feeling well there is some scope for increasing dose to raise FT4 which is only halfway through range.

The goal of Levothyroxine is to restore the patient to euthyroid status. For most patients that will be when TSH is 0.2 - 1.0 with FT4 in the upper range. FT4 needs to be in the upper range in order that sufficient T3 is converted. Read Treatment Options in thyroiduk.org.uk/tuk/about_... Email [e-mail] if you would like a copy of the Pulse article to show your GP.

[Phoenix605]

Divide FT4 by FT3. Good conversion is usually considered to be around 4:1 or less. The thyroid produces mostly T4 with a little T3 it doesnt do the actual converting that is done elsewhere like in the liver. You need optimal levels of the nutrients mentioned by Slowdragon to enable good conversion to take place.

[martinpatrick]

i think your conversion is good enough but you need more levothyroxine. Get your blood test done before 9am talke no meds before and fast. your tsh will be highest in the morning and your doctor will then be more willing to give you a higher dose. Your ft4 can go higher to near the top so you can get ft3 reading of approximately 5.6 for you. The increase in ft4 will cause your ft3 to go up as you have good conversion. Autoimmune can fluctuate a bit. Are you on LDN. definitely worth trying for autoimmune thyroid issues