46 hours into a fast and my ketones are stuck at 1.3 mmol/L, blood glucose 83 mg/dL


(Evan Freethy) #1
  • Currently 46 hours into an extended fast.

  • Been on keto for 2 months.

  • Did a 24 hour fast 2 weeks ago.

  • I did a 48 hour fast last week in which my ketones reached 4.8 mmol/L, blood glucose dropped to 64 mg/dL.

Now I am on my second 48 hour fast, but my body has appeared stabilize around 1.3 mmol/L, blood glucose 84 mg/dL.

I am afraid I am no longer receiving the benefits of the extended fast.

Any insights here?


(Gregory - You can teach an old dog new tricks.) #2

What benefits are you looking for that you are not getting?


(Susan) #3

I would just keep fasting until you feel that you don’t want to fast anymore. The longer you fast from just water or plain coffee or plain tea --the more autophagy you will get (within reason, what your body is comfortable with, not too long either!). The longest I have done so far is 91 hours, I hope to do longer at some point. I am cooking for 4 non-Keto people daily so it can be difficult during my fasting days at times because of this, not because I feel hungry (because I rarely have any hunger, even on my eating days) but because of all the constant criticism I get from them for not eating (being called anorexic, etc).

I have done Keto now for a year and I have never measured anything with the Pee Sticks or Metres or anything so I don’t think that you should worry so much about them, unless you are a Diabetic or have cancer or another disease that requires you to measure this.

Fast as long as you are comfortable with (past 20 days you should see a doctor though). If you are not registering, perhaps it is because you are not doing a pure fast? If you are using HWC, etc as some people like to do during fasting, then it can change the benefits of a full water fast (some people feel even using coffee and/or tea can do this) so perhaps the numbers are only really relevant pure (as it were) for people doing a full water only fast. I would just fast and stop when your body is not comfortable doing it anymore.


(Windmill Tilter) #4

I think it’s more likely you are no longer receiving benefits of measuring glucose and ketones.

Take a look at the GKI charts of folks who fast frequently. There is not a predictable relationship between hours fasted and ketones/glucose. For that matter, nobody really even knows how to correlate a particular GKI to a specific outcome. The GKI “target ranges” you see in “infographics” are completely unsupported by evidence or research.


(Joey) #5

@Evan_Freethy First of all, welcome to the forum… and congratulations on 2 months of keto and some serious fasting efforts!

Without additional context it’s hard to address your primary concern about keto metrics. I’m assuming you’re talking about blood serum ketones (not urine sticks), since you do blood glucose testing, right?

Another important question: are you concerned about ketone levels because you are battling cancer? (In which case, clearly you want to coordinate/consult with your oncologist for GKI metric targets, etc.)

But assuming you’re like most of us who are taking on keto eating for general improvements in health, then - like some above have suggested - stop worrying about ketone levels.

At 1.3 mmol/L you are CLEARLY in metabolic ketosis. Relax about that and enjoy the ride. Ketone measurement is primarily to determine and/or confirm whether you are in ketosis. Since you are not eating carbs (moreover, in your case, you’re not eating anything), then you are in ketosis. Simply put. [Otherwise you’d be unable to type your question out after two months of hardly any exogenous dietary glucose.]

Ketone measurements beyond this point are for personal interest and self-experimentation only. They serve no further function at this point in your journey. Move onward!

Best wishes :vulcan_salute:


(Michael - When reality fails to meet expectations, the problem is not reality.) #6

When reality fails to meet expectations, the problem is not reality.


(Jane) #7

My ketones usually (but not always) peak in the afternoon of Day 3 of my fasts. And then start to drop off. Same with my glucose in reverse. Drops to the lowest by Day 3 then my body starts to make it and my blood glucose goes up.

Black coffee and water only

But sometimes my body does weird things and doesn’t follow this pattern. No biggie.


(Ricky Foutz) #8

It’s not all about ketosis. Extended fasting puts us in a state of autophagy which has tremendous benefits beyond ketosis. Jason Fung and Sadir Ali explain beautifully in their talks.


(Susan) #9

I totally agree with this =).


#10

I pay attention to my GKI while fasting. Sometimes I get below 2 in a couple of days, and sometimes it takes me 4 days, like what’s happening during this fast. My GKI this evening is 1.5. …after 4 days.

But of course BHB rises during the day, so I would expect my GKI ratio to be lower in the evening as I write this. I’ve bounced between LCHF and Keto ever since the early days of Atkins. …so a long time, and I’ve been doing periodic fasting for a few years now. The lowest blood glucose reading I’ve ever seen on myself was 41. I was asymptomatic for hypoglycemia which that reading might indicate which was fascinating to me.

But despite my diet as I’ve moved into my 50’s my overnight fasting blood glucose has risen. It’s still good, 70s and 80s, but much different then when I was in my 30s and 40s when I’d routinely see high 50s and low 60s.

It also seems to have changed during long-term fasting. I get a lot of variability with each long-term fast. My last long-term fast (7 days) by day 4 my morning blood glucose level were in the low 60s and my BHP levels were above 5.

I suspect the variability in my numbers has to do with variable cortisol levels, but that’s just spit-balling. It’s been a hectic week for me, I’ve been busy. During my last 7 day fast was a more relaxing time.

I wouldn’t sweat it. I track all my numbers because it’s fun for me, but I wouldn’t stress over it.


(Jane) #11

I track my GKI when fasting also and find the data interesting.

I can have predictable numbers 3 fasts in a row and then have one that is very different. And could be a more stressful week or additional exercise

:woman_shrugging:


#12

Over the last several years of fasting about the only thing I can predict with any certainty is I’m not going to eat food.:smiley:

I am sympathetic to all those who are new to fasting obsessing about everything. Fasting is alien to most modern western people.

My mind played all sorts of tricks and games with me trying to rationalize a reason to go ahead and break my fast.

I’d obsess over my BHB levels, while I’ve never really had a blood glucose problem I’d still obsess my blood glucose levels as well. Or where my levels were compared to some guru’s graph or research paper I found online. If their data points looked “better” than mine at the same point of a fast I was on, I felt bad about it.

I’d start to rationalize that maybe I should just go ahead and eat something. It’s funny how the mind works. But I stuck with it. The benefits of fasting go way beyond the physical, it’s a mental and perhaps even spiritual practice as well.

OP just needs to hang in there and don’t sweat the data points. Meters are not 100% accurate, your BHB and Glucose levels are changing all the time, You could test one finger and get one reading, and the 5 minutes level test another finger and get a different reading. It’s the trends that are important. Are you achieving your goals? …whatever they are for you. Don’t compare yourself to other people’s reported results. You are an N of 1 trial.


(Windmill Tilter) #13

Age, sex and bmi are all factors. So is insulin resistance. Track it if it’s interesting to you, but it’s not terribly important. You’ll see GKI charts on the internet with “therapeutic ranges”, but they are completely unsupported by evidence/science. If you think I’m kidding, play around with google scholar a bit and look at the research, or rather the complete absence of research on GKI.

If you’re 48hrs into a water fast, 1.3mmol is exactly where your body should be. :+1:


(Ben ) #14

Exercise in a fasted state has always raised my ketone levels.


(Teb Tengri) #16

I’d assume that day 3 peak of Nitrogen loss is at least a bit gluconeogenesis from proteins thus that might explain the peak this time. Unless your diet and stress levels(both life stress and exercise stress) are identical last time and this time then the variability seems normal to me.