When I first started low carb about 4.5 years ago, I used the urine strips a lot. After a while, I graduated to blood (BOHB) tests and the ketonix (breath), especially since I would have multiple tests for blood and breath indicating that I was in ketosis, but the urine strips would indicate I was not in ketosis.
I always considered 0.5 mmol/L BOHB to be the “start” of ketosis. Originally, I was paying $5/strip, then I got it to around $3/strip, and now I pay $1/strip. So, I’m able to test more often.
Testing that way, though, brings up the question of when ketosis really starts. For instance, before going to the gym I have 0.8 mmol/L BOHB, and after the gym and getting to work (no food, only coffee with cream), I have 0.2 mmol/L BOHB, and I’ve even had “low” (below 0.1). Am I no longer in ketosis? (Note that blood sugar goes up during this, from 103 before to 110 after.)
The same happens even at night. Before going to sleep, I can be at say 0.8 or 1.0 and I get up and I’m at 0.3 or 0.4. Am I no longer in ketosis?
Also, some days I’ll test and be shocked either how high my ketones are (anything over 1.0 is very high for me) or how low they are. It seems even keto meals can push me out of ketosis (if ketosis = 0.5 mmol/L BOHB). I have well over 1,200 samples, and I have to say it’s quite difficult to tell why. The only patterns I think I’ve found are that fasting multiple days = higher ketones (always true, though it’s variable) and eating more fat generally means higher ketones.
So, what is ketosis? Is ketosis still defined as >0.5 mmol/L BOHB?