Which is more accurate, and why: Ketone blood monitor or breath monitor?

(Empress of the Unexpected) #1

I’ve heard arguments for and against each. What is everyone’s experience? If you have both, how do they correlate?

(You've tried everything else; why not try bacon?) #2

Like the urine sticks, the breath monitor measures what is wasted. Of course, even the blood monitor measures ketones that haven’t been used, not how many ketones are being made and used.

I participated in a thread with someone who believed that breath monitoring was more accurate, and when I took a look at the study offered as evidence, the principal investigator turned out to be financially involved in a company that made breath monitors. I found the study quite questionable for other reasons, as well. For instance, I don’t know if it is reasonable to assume that acetoacetate, acetone, and β-hydroxybutyrate are always produced in a fixed ratio. Furthermore, how would we go about defining “more accurate”?

The company in question appears to have gone out of business, because nothing came up when I Googled it.