In part 3 of this Exclusive Interview, Michael Irwig explains testing for low testosterone and the variety of testosterone tests available in a discussion with Diabetes in Control Publisher Steve Freed.
Michael Irwig, MD, FACE, is a general endocrinologist at George Washington University in Washington, D.C.
Transcript of this video segment:
Freed: And is there more than one way to test for testosterone?
Irwig: This is a very complicated question because if you go to just LabCorp or one of the major labs you can often have a menu of over 15 different testosterone labs to choose from. So, which do you pick? There’s total testosterone. There’s free testosterone. There’s bioavailable testosterone. You could actually calculate some of thes, like the free and the bioavailable, if you have the sex hormone-binding globulin. And then even within these individual tests, there are different ways to do it. So, for total testosterone, liquid chromatography mass spec is the most accurate method. And so, that’s definitely the preferable way to go. And men should have their levels tested in the morning and fasting because that’s on average when they’re going to be highest. So, have nothing to eat or drink in the morning other than water until they get their blood test and then they can have breakfast.
Freed: Is it necessary to test the other aspects of testosterone like you just mentioned?
Irwig: So, I definitely would with a man who has diabetes due to overweight or due to obesity because they can have this abnormality with the sex hormone-biding globulin. So, what happens is that their total testosterone may end up being low, but their free testosterone or bioavailable may actually be normal.