Answer:
The health industry has been searching for a quick and easy glutathione test for years, but currently it is still quite difficult to accurately measure for someone like you and I in a doctor's office like you would a blood glucose or cholesterol test. If we did, that would certainly be very helpful to everyone. I am confident one day we will have it.
One reason is the sample deteriorates quickly. There are some labs that will test your blood sample for glutathione, but it can be expensive and has to be dry iced overnight, and I personally don't have a lab that I recommend. Levels can rise and fall throughout the day depending on the method of raising glutathione they are administering, so it's really hard to be accurate.
The labs that are used for published medical studies are likely the best, but they are not accessible to you and I. So the one thing we know is that those labs have determined that Immunocal is effective in raising glutathione values, as the PDR listing explains:
"IMMUNOCAL is a U.S. patented natural food protein concentrate in the FDA category of GRAS (generally recognized as safe) which assists the body in maintaining optimal concentrations of glutathione (GSH) by supplying the precursors required for intracellular glutathione synthesis. It is clinically proven to raise glutathione values (Lands et al, 1999)."
The best way for a person to tell if their glutathione is raised and sustained is improved health in the many aspects covered on my site. The results speak for themselves and keep thousands coming back for more every month. I have never missed a day of Immunocal in almost 5 years now and would never leave home without it!
You can order Immunocal for yourself here.