Your results please? Fasting non fasting - Thyroid UK

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Your results please? Fasting non fasting

lisan1 profile image
12 Replies

Trying to figure out if it's best to have the TSH test fasting or not since I've read that fasting suppresses TSH but generally people advice you to fast.

So anyone had tests done at same time of day and fasting non fasting?

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lisan1
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12 Replies

Yep I did my first lot of tests after I'd had breakfast (as I was a noob and didn't know about the fasting thing) - my TSH was 3.43 (range 0.27 - 4.20). I did another test 6 weeks later, this time fasting early morning and my TSH was 4.95 (same range).

lisan1 profile image
lisan1 in reply to

Thank you!

Oh, were they done at the same time in the morning?

in reply tolisan1

Yes.

lisan1 profile image
lisan1 in reply to

Thanks!

AiryFairie profile image
AiryFairie in reply to

Did you take any thyroid replacement tablets (Levothyroxine etc) before the

tests?

in reply toAiryFairie

No, I was not on any Levo at that point, I was still undiagnosed. :) I only started Levo 2.5 wks ago.

AiryFairie profile image
AiryFairie in reply to

Good job you found out you should "fast" then, eh? Well done! I hope you feel better soon.

in reply toAiryFairie

Yes it is! And thanks! Good luck with any future testing. :)

Clutter profile image
Clutter

Lisan1,

Fasting doesn't suppress TSH but TSH does drop after eating and drinking.

AiryFairie profile image
AiryFairie in reply toClutter

I feel a bit of a numpty. It's only since joining HealthUnlocked I learned the significance of fasting, not taking Levo beforehand, and getting the blood test done early as possible. Two months ago, feeling increasingly unwell, I asked to be tested again. Unfortunately I had the test at 3.00pm, after Levo, breakfast and lunch, and was well in range, so no increase in dose for me! I'll know next time! That's if I can even persuade GP to let me have another test so soon. :(

Clutter profile image
Clutter in reply toAiryFairie

Jannie1957,

Well none of us is born knowing these things so no reason why you should feel a numpty :)

If your thyroid levels are optimal it is worth having your ferritin, vitamin D, B12 and folate checked as they are commonly low/deficient in hypothyroid patients and symptoms can be very similar to hypothyroid symptoms.

AiryFairie profile image
AiryFairie in reply toClutter

Thank you Clutter, I am addressing those issues. After a few weeks of supplementing, my "brain fog" is significantly better. But low mood, sleeplessness, lethargy and constipation remain (like before original diagnosis). I will try with GPs one more time, but if they won't test me again, I may then go down the home-testing route. At least I now have knowledge and options.

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