Low ketones after fast?

(doggonnit) #1

Newbie. I did my first 22 hour fast. I was expecting high ketone levels, but they were low. before the fast they were 30ppm in the morning. After fasting they were around 10ppm. Wanted to test before a meal out of curiosity. I thought the thinking was the ketones go way up after fasting? On a Ketonix meter graph, this is the yellow area. Am I misunderstanding?

(Michael - When reality fails to meet expectations, the problem is not reality.) #2

22 hours is not very long. Yes, you could have generated more ketones (acetoacetate and β-hydroxybutyrate) but less acetone. The most likely explanation is simply you used them more efficiently and completely with a little less glucose in the way. You need to record data for a month or two to see your real variations and/or patterns.

(Bob M) #3

When I was comparing breath and blood ketones, they did not always travel in the same direction. For instance, I could have BHB (blood) ketones as say 1.0 mmol/l, and have breath ketones all over the place relative to that value. (Note that Dave Feldman just did a test, though, where his breath and blood ketones tracked fairly well.)

Since I’ve only been using my ketonix lately, it’s not clear to me what causes it to go up or down. I thought going up meant I ate higher fat the day before (only test at work, in the mornings mostly), but I specifically ate higher fat one day and got a lower value on the ketonix.

These are my current values for instance:

Note that when I first got this, about 4 years ago, I regularly got in the 60s, 70s, and even 80s. Now, I see a rare 50s, but I’m usually between 20-30.

BW = body weight training. HIIT = high intensity interval training.

(Bob M) #4

Oops…that “(ate higher fat yesterday)” on 8/20 shouldn’t be in there. I added that just now, but I think what I meant by “Hmm…thought it would be higher” was that I felt as if I was in deeper ketosis. I can do that…sometimes. The problem is that I don’t have any strips for blood ketones anymore.