The longest fast I have gone is for 24 hours but I didn’t track my ketone levels and neither did I track my blood glucose. Being on a carnivore WOE, the goal is not to be in ketosis. However, we can go in and out of ketosis quickly and with ease.
I decided to go for a longer fast which is for 36 hours with my last meal on September 24 dinner time with my next meal only on September 26 breakfast time to complete the fast. This time, I decided to check my ketone levels so I can kind of figure out when exactly do I get to a state of ketosis. My last meal was a generous portion of grilled pork.
I forgot to take a photo of my ketone levels on the 12th hour of fasting which was only 0.4 mmol/L which meant I wasn’t in ketosis yet when waking up. I only got into nutritional ketosis on the 16 hour mark of my fasting with my ketones at 0.6 mmol/L.
On the 24th hour of fasting, it went up to 2.2 mmol/L which is well within the optimal range, it being 0.6 to 3 mmol/L. I was not feeling hungry or starving although I have encountered hints in tiny waves but I was able to hold off. My energy was superb and my focus or mental clarity was exceptional. I was very productive before and after the 24th hour mark.
I actually thought that I would have a hard time sleeping on an empty stomach — especially without any meal for the whole day. But guess what? I thought wrong. I did not have any trouble sleeping at all. Perhaps it was because I did not just lay around the whole day during my fast. I actually did some light workout in the morning and I also did an easy yoga session in the afternoon.
When I woke up, I was already on the 36 hour mark of my fasting. It was a bit different this time because I woke up with a sort of acid feeling in my stomach. I woke up feeling incredibly hungry. Before breaking my fast, I checked my ketone levels and they were up to 4.4 mmol/L which is already on a therapeutic range. To my knowledge, this is where autophagy happens and you’ll be starving cancerous cells out.
Though I was on the therapeutic range, I did not however feel so good. Perhaps I needed already electrolytes at that point or my body was really signaling me to eat already. My hands were shaking and that acidic feeling in my stomach felt worse by the minute. I decided to check on my blood sugar levels and it was quite lower than the normal range — my waking blood sugar was now at 57 mg/dL.
One thing I had to struggle with on breaking my fast was keeping my food down. Because of the acidity that built up in my stomach, I vomited my first intake of food; I tried to eat a few strips of bacon and chicken. A couple of minutes later, I did not feel good at all: I felt nauseous and dizzy and afterwards, I puked. I tried to eat again and the same thing happened. I knew I was going to get in trouble if it kept happening, so I decided to try drinking milk kefir first before having solid food again. Thankfully, that worked. Straight after drinking milk kefir, I felt so much better — I no longer felt nauseous and I was able to keep my food down.
My recovery was quite fast after that. My energy levels were back to normal: I was feeling energetic again and I was able to complete my tasks for the day. Honestly, I felt fantastic! I will do the fast again when I’m primed well for it just like before. Maybe the 36th hour mark won’t be so uncomfortable anymore.
Feel free to comment any suggestions to help me fast longer. ‘Til next time!
Thank you and have a great day!