best test for optimizing selenium levels

[kpfleger]

What is the best test to determine selenium levels?

Selenium is very important but it is one of the essential nutrients for which there is a fairly narrow window between too little & too much. Further,  some of the best dietary sources can have widely varying selenium content (eg, many-fold differences across batches), so it would be nice to have a good way to assess whether a body is getting too little or too much.

How good are using commonly available selenium blood tests? LifeExtension.com offers one as do many similar direct-to-consumer blood test vendors, most using LabCorp or Quest, but those 2 lab companies seem to just offer a basic serum test.

I've heard that assessing selenoprotein P (SEPP1) would be better and such a test exists, but maybe it's only commonly available for research purposes or just not generally available? For example, I don't see such a test from any of the above mentioned places.

I don't see this topic addressed in any other threads in these forums nor in Michael Rae's "Nutrition and Supplementation for Veg(etari)ans".

[Alex K Chen]

Maybe ask https://scholar.google.com/citations?user=Qi0AwfEAAAAJ&hl=en ?

He's at GRC

[IgorF]

Chris Masterjohn in his guide wrote that serum selenium assessment "is the ideal marker", blood selenium also serves good enough for the similar purpose.

I used to take blood test in different labs (outside the US) and in all cases it was spectrometry-based method of assessment (don't remember from head the exact name of it) which is pretty good for quantitative analysis and should not produce mangled results or be fooled by interferring with other substances (e.g. like biotin fooling many tests for particular big molecules).

From the way selenium gets into our flow it seems the metabolism should not bring big surprises, e.g. quantitative test if in the labs ranges is representing the status accurately but there is always a chance for some SNPs not known / not well studied, so for corner cases of too low or to high perhaps it could worse to try to find more sofisticated tests, but first thing is to check the symptoms of deficiency or poisoning with a medical doctor and do 2-3 tests for sure.

 

Br,

Igor