Effect Of Fasting On Bg

[BarbaraG]

I'm interested in hearing experiences of people who use different types of fasting regimes (e.g 16:8, 5:2, 24 hr, 36 hr, longer) and what difference it has made to your BG.

I got of all meds (and consequently off home testing) 3 years ago following major weight loss, but, unfortunately..... You can guess the rest. I resumed metformin a year ago and dose increase to 500mg twice a day in April. I started eating LCHF eight weeks ago, and earlier this week went for the review of annual test. Lipids all good, but HbA1C 62 - ouch!!! I asked for test strips and was told they can no longer prescribe them. So, I've bought a new SD Codefree meter and strips, arrived today.

First test - about two hours after (low carb) breakfast was 6.8. Before lunch 7.1 (eek), 1 hour after 6.5. At first glance, those wouldn't really explain the HbA1C - but I do recall that I used to have a strong dawn phenomenon.... I'll find out tomorrow. Plus I was only eating low carb for 7 weeks before the blood draw, and before that VERY high carb.

Anyway, sorry for waffling on..... What effect do you see on your BG from the fasting you do? TIA.

 

[bulkbiker]

Personally I get my lowest levels when on an extended fast (up to 5 days). Since giving up breakfast (day after diagnosis) I effectively fast for 16 hours from dinner until lunch the next day every day and find it quite easy to extend that to up to 40 hours. I would wait a few weeks until low carb adapted before trying fasting as the hunger pangs lessen significantly.
Sounds like you are all set up for success with test strips aplenty so good luck. If you need any more tips let us know.
All the best
Mark

 

[jonbvn]

I find my FBG levels about 10% lower after a fasting day (5:2).

 

[KevinPotts]

Big drop in BG like Bulkbiker when on an extended fast (4-7 days), but it's not for everyone

 

[chalup]

I have tried intermittent fasting and I find my sugar levels just keep steadily climbing until I eat something.

 

[bulkbiker]

I have tried intermittent fasting and I find my sugar levels just keep steadily climbing until I eat something.

Really? How long do you fast for?

 

[walnut_face]

I find that cutting a meal (or 2) out helps to bring down readings from about day 3 onwards. But I have found the biggest contributor to be snacking, or grazing, even on nuts and the like

 

[Indy51]

Mine has improved dramatically since starting a strict 8 (or less) compressed eating window. I usually do it most days, with only occasional lapses. I've always been a breakfast person, so I have breakfast, then I eat my main meal anywhere from 11:30 to 14:00. Then I fast until the next morning.

It works well for me because I live alone and can suit myself about meal times - it also works because I'm less likely to get positional reflux at night which has tended to be an issue for me (hiatal hernia). The later in the day I eat, the less likely I am to get a good night's sleep.

My fasting BG has normalised for the first time since diagnosis 4.5 years ago. I'm usually between 4.5-5.5. I'm also getting lower levels before the second meal.

I recently did a 3 day fast for the first time and was getting ketones by 24 hours and just before breaking the fast I nearly reached the 1:1 level of BG:ketones that is recommended for therapeutic ketosis - 3.4:3.2! The only real issue I had during the fasting was a low grade headache the longer the fast went on.

 

[chalup]

Really? How long do you fast for?

I have gone as long as 3 days while ill but while healthy, about 20 hours, several times. Just keep drifting up and up. If I go more than about 6 hours without eating something while awake I start to climb as well.

I also have pretty bad dawn phenomena even after 6 months of very low carb

 

[bulkbiker]

Sorry to hear that.. I haven't had breakfast since I was diagnosed nearly a year ago but bloods usually go down or stay the same when not eating.. my DP took ages to normalise too but I don't think I have gone higher when not eating. Do you have milky drinks when you get up? Just a thought...

 

[Brunneria]

I find that IR for 16:8 is a waste of time for MY body. No impact on fasting bg, and no drop in baseline bg levels.

However, as soon as I moved to 24 hr fasts, things changed. Luckily I was wearing a Libre sensor at the time, so was able to watch it unfold in detail.

Basically, if I fast from evening meal until the next evening meal (approx 24 hrs) then my bg trundles along in its usual tracks until I miss lunch. From then until I eat (midday until that evening meal) is when I see the benefits. So I am sort of doing a string of 24 hr fasts, Monday to Fri at the moment, with just one meal a day in the evening. It seems to improve my insulin resistance wonderfully, but is having precious little effect on my weight.

Unfortunately, life keeps intruding. A birthday lunch at work for a colleague, and then yesterday a long intense morning that sent me into too low bgs, so I ended up treating it like a hypo. But hey, this is a long game.

I would like to try a 72 hour fast, because Fung shows how excellently these are at depleting glycogen reserves and reaching a nice steady higher metabolic rate. But I am still running scared of going to sleep when hungry. It is beginning to feel like a phobia. Much stronger barrier than I anticipated, when I started this fasting lark.

@chalup I have had that steady rise, at times. For me, having a fat fast (fasting from carbs and protein but with either coffee and cream a couple of times in the morning, or havning a Fat bomb as elevenses, will completely stop the rise. Weird but true).

 

[chalup]

Nope I dont drink coffee and only drink tea when sick and take it plain. I am lactose intolerant so don't drink milk at all. I drink water or diet coke and try to stick to mostly water.

@Brunneria Yep a fat bomb does the trick for me as well to stop the rise and that is what I usually have for breakfast, either that or a cheese string.

 

[Heathero]

Am I misunderstanding but you are type 2 fast and take insulin while you fast for days? Can/ do type 1 fast for days?

 

[chalup]

I do not think any of the people who have posted on this thread use insulin, I do not. I could not speak to the safety of fasting for a type 1 and I know nothing about insulin management. That might be a good question for starting a new thread.

 

[Robbity]

I have tried intermittent fasting and I find my sugar levels just keep steadily climbing until I eat something.

I've seen this happen too sometimes, but eventually I've seen a slight reduction in levels overall. I think probably our livers may keep on dumping until their reserves have been depleted.

Robbity

 

[Kristin251]

I'm type 1 and not eating makes it worse. I need to eat at BF but could fast until dinner but not interested. I like my small meals and can take small doses for it. I inadvertently found out fasting requires much more insulin than if I eat for DP.

 

[Brunneria]

Am I misunderstanding but you are type 2 fast and take insulin while you fast for days? Can/ do type 1 fast for days?

Fasting for insulin users takes care and knowledge, but it is definitely possible.
In fact it is regularly used for basal testing.
Also, Jason Fung uses it in his clinic, where he does extensive fasting and finds that type 2 diabetics respond extremely well to it - with impressive reductions in blood glucose, use of meds and insulin and weight loss. Of course, this is under medical supervision.

So yes, fasting is perfectly possible for type 2s, but it requires a good understanding of how to reduce medication at the same time in order to avoid hypos - so unless someone already has that, they will need medical supervision.

 

[Clivethedrive]

Best way that works for me.....4 small carb free meals fairly evenly spaced...keeps my body from reacting and seems to prevent swings,portion control a must,i'm treating my bs like they are an invalid...since doing this my bs has not been over 6.5 at any time and is consistantly 4.5 to 5 mmols am fasting

 

[Bluetit1802]

I am currently experimenting with an 18/6 fast. I skip breakfast and eat lunch and tea within a 6 hour window.

The first full week I saw drops in all my baseline levels (fasting, before lunch, before tea and bedtime). I was delighted.

I am currently part through my second week and seem to be regressing with the exception of the before tea level. This MAY be due to having opened a new tub of strips. My eating and routine are unchanged. I am wondering if it is worth it.

 

[Brunneria]

Well, I think there are two main reasons for fasting (for diabetics), one is to reduce insulin resistance, and the other is for weight loss.

I want both. But I haven't a clue why people would want to do it, unless they wanted one or both of those things...