For the last 40 days I’ve been checking my blood ketone levels (using a Nova Max and horribly expensive test strips) and at the same time checking my breath acetone levels using a Ketonix. Based on my blood levels I haven’t been deep in ketosis but I expected there to be some sort of correlation between the two. The Ketonix is marketed as a way to check to see how far into ketosis you are, an easy way to check your levels without needing to buy expensive test strips. I don’t know if I just got a defective one that always shows high levels of acetone or what but thus far I haven’t seen any reliable data coming from the ketonix. I’m going to give them the benefit of the doubt and I actually just ordered a second one so I can see if it’s a defective one or not. I’d love to see clear, defined results like this guy. Honestly I’d really like to have it work but my guess is I’ll be returning the new one and eating the shipping charge.