Anyone used ZRT lab blood spot test for IGF-1

[Keepfit1]

Has anyone used ZRT for blood spot tests for IGF-1 or anything else, were they accurate?. I dont usually use blood spot for Hormones but the nearest place to get IGF-1 tested in the UK is 400 miles away, they dont do it by mail, apparenty it goes off or something. I can buy in UK a ZRT blood spot IGF-1 which they send to me and then I finger prick and put about 10 spots of blood on to a piece of paper and THEN send it to the US and apparently its good for up to 30 days until it reaches lab so no problem with mail. I am sceptical so wondered if anyone has used them in the US or elsewhere, the website looks quite impressive though. I note they also do all the other hormones using same method and spit?

 

[WhosThat12]

I'm also interested in finding info on ZRT.. I'm doing research for it and came across your post.. hopefully this bumps it and someone answers.. I'm in the US

 

[Nelson Vergel]

Testing IGF-1, just like testosterone and estradiol, is usually done using liquid chromatography/mass spectrometry. However, I know how difficult it is to get those tests in the UK or Canada.

I personally would not waste my time measuring IGF-1 since is changes during the day depending on our fasted/non-fasted state. It also spikes early in the morning and right when we get hungry.

Blood spot tests use immunoassays that may present interference with supplements like biotin used for "hair loss".