So I finished a 5 night fast (close to 6*24 hours) yesterday. Now I’ve never had much trouble with keto breath even when eating a pretty strict keto diet, and I’ve even fasted for 5 nights before without this issue, but this time I exercised for about 2 hours, first 40 minutes spinning then 40 minutes HIIT, on day 3 of the fast, and since then I’ve had the worst keto breath. That night I could barely sleep because my mouth would constantly fill up with air smelling like rancid fish oil coming out of a jerry can. It’s gotten a little better since then, but day 4 and 5 was still pretty bad. When I started eating again yesterday it improved even more, but the taste is still there, and when I did some more vigorous exercise today it came back as strong as ever, albeit for a much shorter time (I also exercised for much shorter today).
It’s not just my breath either, I my armpits smell the same and I can smell it when I go to the toilet. The worst is my earwax which smells like it could spontaneously combust at any moment. I’m not one to be tempted by carbs at all, but right now I’m a little tempted to go buy a chocolate bar or even just boil a potato just so I can get rid of this bad breath (although I’ll probably just add an onion to tomorrow’s stew).
For the record, I didn’t measure my ketone levels, I don’t have that ability, but I’m pretty sure I was in ketosis before as I already experienced the increased energy and mental clarity people talk about, and I didn’t experience any further increase during fasting. I also broke my fast with some aged cheese and a fathead pizza when I usually go for some macadamias and a salad-heavy burger. I would not recommend going the cheese route…