Hypoglycaemia on a shorter fast (3-4 days). I need your wisdom

#1

Hi.
I am new here. So hi to you all. Thanks for this great forum.
Apologies for the length of this but I want to put as much info in as possible to help you all formulate answers for me.
Please see below for the background section for info about me which may help you answer me.

My Question: Earlier this year I did two attempts at a short fast of 3-4 days - only broth and water, lots of salt and one coffee with cream a day. My aim was to reverse my small weight gain, AND just to just see if I could do it because I would like to access the anticancer and other long term metabolic advantages of fasting.
My problem is this. On both occasions I sailed through Day 1 and 2. No hungries, no grumpys, no low energy. However on the morning of day 3 (72 h) I got out of bed and almost fainted. I was clammy, dizzy, shaky, racing pulse, low bp. So I sat down and took my bloods readings. My blood sugar was 3.6, ketones 2.6. My morning blood sugar is usually around 5.0. So I had 3 or 4 macadamias and a cup of tea and in maybe 40 minutes I felt completely fine and continued my fast with no problems for the rest of the day. Next morning (96 hours)… same thing, felt like full- on hypoglycaemia. Blood glucose at 3.1, ketones now up to 4.9. Felt f**n terrible. Again I ate some macadamias and had a cup of tea and felt ok after 45 minutes. This time however I decided to break the fast at this point… no problems from then on.
About 6 weeks later I gave it another go… Same thing. Day 1 and 2, no problems, not even hungry. Got out of bed on the Morning of day 3 a (72 hours) - faint, shaky, clammy, high heart rate, low blood pressure. Blood glucose 2.7, ketones 6.0. This time it took a good hour to feel better after eating a handful of macadamias and a cup of tea. I broke the fast at this point.
So. What am I doing wrong? I have recently found Richard’s fasting calculator (fantastic!). This says that I actually do not have enough fat to fast without additional dietary fat. Also at the time I was not actually in ketogenisis, I was just low carb. Is it just a combo of the above two? ( ie I was not fat adapted so even tho I made ketones, my body didn’t know what to do with them? AND my body couldn’t get enough energy from my fat reserves)? Should I try again now that I am properly ketogenic? Is there something else I have missed? I really don’t want to hurt my body or damage my metabolism so I am anxious about another attempt.
Please help! All wisdom accepted. Thanks in anticipation.

Background: I am female, 53, probably perimenopausal ( dunno. How do I tell). I have been doing IF on a daily basis for 5 years (16/8 - 20/4 depending on the day and how I feel ), low carb for 3 years, but only full on keto for the last couple of months. I am not prediabetic, based on fasting blood sugar ( below 100). Other blood work ok ( triglycerides below 70). I am 165 cm and 58 kg so not overweight, however my dexa scan shows a body fat of 27% which I am NOT happy with. My weight has been increasing over the last 9 months and I have possibly added 3 kg ( don’t weigh- I go on how my clothes fit). I have not exercised seriously for about 2 years due to a persistant low back injury. I am now starting to get back into bodyweight exercises with an aim to more serious weights in the very near future.

#2

I wonder if you are experiencing an electrolyte imbalance. After eating nuts, you say you feel better. And nuts have electrolytes, like magnesium, and possibly sodium, too (if they are the salted variety).

#3

Thanks Fiorella,
I did consider that. I do take a daily magnesium supplement and continued that during the fasts. I also was conscious to keep my salt (NaCl) up during both fasts. On the second one I felt like I was constantly at a salt lick! I suppose there are other electrolytes I could add in though. Or try a general electrolyte replacement drink. If I could find one without sugar…

#4

There are recipes on this forum for ketoaide. You can also buy electrolyte tablets (like a multivitamin, with just minerals/electrolytes). Or perhaps take a multivitamin, too.

What type of salt do you use? Salts like sea salt have micronutrients (zinc, manganese, selenium, iron, as well as the common electrolytes, like potassium and magnesium).

You may also want to look into drinking mineral water…like Pellegrino. Check out the nutritional data on the bottles and buy the mineral water with highest mineral content. Pellegrino tends to be higher (than for example Perrier).

#5

Ok thanks for your help. My normal salt is pink Himalayan.
I will look at the keto aid recipe. And the mineral water idea!

#6

Sounds like you figured it out, your glucose was low, but not crazy low (by fasting standards) but when your body isn’t used to be down that low it’s screw with you big. As you figured out not being on a fat metabolism is a huge disadvantage when fasting. But the racing heart thing is usually potassium many people never have to worry about that one, I personally go low on that easy. My resting heart rate will sit at 100-115bpm for no reason at all, hear my heart beating when I lay down, etc. Eat an avocado a day leading up to the fast and grab some potassium pills but go easy on them. Most pills will only be around 3%DV but only a few is all it takes to keep you good, don’t try to get 100%, won’t turn out well. I also drink a lot of smartwater while fasting, like the taste and its a slow electrolyte infusion throughout the day.

#7

Thanks ifod14
I will give my body another few weeks on keto to fully fat adapt. And then give it another shot with a full suite of electrolytes.

#8

Where did you find Richard’s fasting calculator? Never heard about this but now I’m curious.

#9
(Stephen Price (Lythix)) #10

I just finished a 72hr fast and shared my blood sugar and ketones on Facebook.
It’s my longest fast and first time to measure. The post brought out some people telling me I would be having a mild hypo with blood sugar of 3.9. ketones were 3.3.
Following morning after fest, I was 0.9 ketones and 5.6 glucose.
Should I be worried or did I do something wrong? I felt fine. Definitely hungry and maybe a tiny bit light headed occasionally perhaps a couple of times on the last day.

(Penny Vogel) #11

I just finished a 92 hour water fast on Sunday night. I had one exogenous ketone drink/day. I decided to break the fast early because I had a reading of 4.8 as a ketone reading and a blood glucose reading that was too low for my Precision Xtra metre to read “LO”. which means it was lower than 1.2 mmol/L . I still had brain fog, no energy, terrible sleep. My guess is that my body had not switched over yet. My question is - Is it okay that it got that low?