Thyroid function test - empty stomach

[BlueTitsRock]

Have this test next week. GP said it is a non fasting test but a friend said it is better to go without having anything to eat before as the test picks up hypo issu a better It is at 10:30 so could cope with a coffee until then.

Anyone with some knowledge about it? I have hypo symptoms by the way.

I suspect it makes no difference, but it can't hurt. I've seen this paper used to suggest that TSH is higher when fasting, but I think the study is completely flawed: www.ncbi.nlm.nih.gov/pmc/articles/PMC4171896/

They tested when fasting, between 7:30 and 8:30am, then told the subjects to go away and eat, and tested again between 10:30 and 11. The second results have a lower TSH.

It's well known that TSH varies throughout the day, with an early morning reading being higher than late morning, so the difference between the readings could well be down to this alone.