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Low BG on low carb

NickiSanta

Member
Messages
17
Type of diabetes
Prediabetes
Treatment type
Diet only
Hi

I got a pre-diabetes diagnosis in December and after reading and researching I decided to alter my eating to low carb.

I test before and after meals and my fasting level.

I've managed to get my readings into the 4s and 5s, but several times a week I catch my BG in the 3s . This is usually before a meal, indicating I might have waited too long, but I've also had "hypo" symptoms such as racing heart, chills, anxiety and tiredness at times when my BG is in the 4s or 5s.

I don't understand why my BG can dip to 3.2 or 3.8 (also following retesting) with my current diagnosis of pre-diabetic. From what I understand this is rare in non diabetics and DT2.

Is this all down to just being a little late with meals and eating low carb?

Thanks

Nicola
 
Hi Nicki,
I don’t think it’s a specific meal, or lack of, which are dropping your BG levels. You need to consider the whole picture. You’re pre-diabetic so not officially insulin resistant, as T2.
So you have gone low carb, so depending on the rest of your lifestyle and general activity levels, you will generally store less glucose in your liver and muscles. If your body doesn’t dump that reserve into you blood stream quick enough you could head into a hypo. But then the stress of entering a hypo can also trigger the release of your reserved glucose. Which could explain why your numbers don’t quite add up.
From my experience, the first few months are the most erratic, while your body gets use to a different regime. You should start to see settle after a couple more months.
You could be also placing yourself into Ketoses. If you don’t already know this is when your body switches from using carbs for energy and starts using your body fats.
 
I would argue that 3.8 is pretty common for non diabetics before a meal. The reason T1s have to be paranoid about it is that injected insulin on board can make them go much lower. Likewise some non diabetic people feel a bit faint and hungr y before meals.
There's an interesting study here about the blood sugars of 153 non diabetics who wore a continuous glucose monitor
(US units so you have to divide the blood sugar readings by 18)
Continuous Glucose Monitoring Profiles in Healthy Nondiabetic Participants: A Multicenter Prospective Study - PMC (nih.gov)

28% had one or more hypos (<3.9 in the US)
Overall they spent on average 15 minutes a day with a bg less than 3.9, but the ones who had hypos had a median below range time of an hour...
 
Thank you for your replies

My carb intake is very low (less than 22g a day), and yes I'm probably in ketosis. I didn't know I could lower my blood sugar enough to feel ill just by diet alone. :O

I guess that means water fasting is out of the question. I'd heard it can reset all sorts of things including blood glucose problems.
 
Part of the normal process of glucose regulation is that when the liver senses lower levels it will dump glucose into the blood to bring it back to “normal”. This is why we all don’t go into a coma if we skip a meal or two. Some medications (including insulin and some other diabetic medications) or a few unusual conditions might interfere with or override this but otherwise it’s pretty reliable. When fasting people reach a certain low point and this mechanism kicks in.

The other thing is if you are used to a particular range your body thinks this is “normal”, whatever that might be. It’s why some can walk around with horribly high levels and be unaware of it and also why when they lower their levels noticeably they feel as if they are hypo even when their levels remain above 4mmol. Known as a false hypo. The body can reset a new normal once it becomes accustomed to it after a while.
 
Unless you have weight to lose (adipose fat / abdominal spare tyre) then going into ketosis is probably unecessary. There have been studies done that show that running with sugars below 5 mmol.l is not actually beneficial and the mortality curve starts to rise below 5.4 mmol/l. My doctor prefers me to have a target of 7 mmol/l and my hospital consultant advises 12 mmol/l as his recommendation. Needless to say I set my eyes on about 6 and am currently running an average of 6.4.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2258341/
 
If you were doing the Atkins diet, which starts off with a couple of weeks at 20gm a day, you would be more than ready to start to add small amounts of carbohydrate into the mis.
As the Atkins diet has been done by so many people, it is probably well investigated, and as you are equipped with a meter you can check to see at what levels you are still in normal numbers - so heading out of the prediabetes range.
Did someone advise you that going so low carb was a good idea?
There are so many willing to give advice without having actually done what they advise.
I knew that I did well of 50 gm of carbs a day, so that is what I went to and reversed my Hba1c of 91 down to 41 in 6 months - I really think that you don't need to go so low carb to deal with prediabetes, it is a powerful tool to tackle problems with weight and blood glucose, and your glucose regulation might really not need to be hammered so hard.
 
This study utilised intensive medical (drug) treatments and possibly the lower levels associated with hypos rather than stable normal levels and potentially side effects of medication as well as likely underlying increasing insulin resistance. As such surely that’s quite different to non medical methods (like low carb and increased insulin sensitivity that results) so not especially relevant to a non medicated approach.
In fact the study itself says “This leaves us with the intervention itself as the possible culprit—the highly intensive treatment (often multiple insulin injection regimens combined with multiple oral agents) aimed at reaching the target of HbA1c <6.0%.” and “The problem of increased deaths may in some way be linked to higher doses of injected insulin in combination with stimulation of endogenous insulin secretion (by sulfonylureas) or use of insulin sensitisers (metformin and thiazolidinediones), or both. If insensitivity to insulin is actually a protective mechanism, rather than the pathological outcome of overeating as it is perceived today, then perhaps trying aggressively to overcome it may have adverse cellular effects that we have not yet begun to understand.”
 
A valid observation. But looking at the overall T2D cohort, the position at the moment is that the majority are following current NICE guidelines and Eatwell or worse. The number of people using a sensible diet to control their condition is definitely a minority. There are also reports coming out that Low Carb diets are also associated with increased mortality, but not increased CVD outcomes. LCHF in its current form is a recent introduction, and does not have long term studies to support its safety yet. We here are guinea pigs in that respect. We have yet to really see the implications of that diet in the long term. There is longer experience and review of restricted calorie low fat diets for instance, and some of them have been shown to be injurious. Most of the diet research is connected to the Health and Fitness industry, which forms the basis of our Nutrition theory. The weight loss industry is also involved but do not fund research to any significant level. The medical use of diets and research do not really seem to team up except in Eatwell.

Whilst it is difficult to see why a low carb approach should be associated with an increase in mortlity since all it is doing is mimicing 'normal' non diabetic range of bgl, it is nonetheless an intervention which may be inducing its own co-morbidities. We do not at the moment know for certain that keeping bgl in target range as a normal non diabetic actually reduces all the complications linked to T2 diabetes. I am hopefull that it does, but we see evidence from bariatric surgery follow up that it is not the complete picture. The remission is not a cure, and it is not pemanent.
 
But we are talking - here in this thread - about low carb not the general cohort so again I make the point this study is not particularly relevant to this specific conversation.

Bariatric surgery is a different approach to low carb and it’s successes and failures are once again not the same thing as other methods of control and it’s results should not be extrapolated directly across to low carb methods, even whilst there may be links between them.

Please link the reports that low carb alone is increasing mortality or inducing co-morbidities. This claim is quite alarming to see and needs supporting

I accept that low carb to treat diabetes is a new approach on any sort of widespread scale. Nor are we convinced yet that it does reduce all the complications but it certainly is at least helping many of them so far. Maybe we won’t stop every sign and symptom in the long term but it seems to be doing an awful lot better than purely medication approaches.

No one here, and certainly not I, is suggesting cure.
 
You are putting the blinkers on. The paper is not apparently relevant to the OP but may well apply to readers of the thread. Your point is valid, but there is still open ground around it that other papers show similar stories and outcome. The curve is a bathtub curve, and while different medications affect the actual inflection point, there will come a stage where the curve changes slope and rise and going too low seems to be harmful. even in ketosis, our brains and nerves need glucose, which we synthesise from protein if necessary. but that is an inefficient process, and is limited to provide the essential functions for survival. ketosis is actually a form of starvation, and yes, we do appear to be able to sustain a lifestyle with it, but only while there is fat in lipid form to use for overall energy. As I said above, the keto diet is a new kid on the block, and we need to see what happens as it reaches maturity. as an ex-smoker, I am indeed paying the price now in later life.

My twopennoth, i.e.my opinion, people here are encouraged to aim for ketosis and follow a restricted diet (compared to my medium low carb variant) that seems to cause stress in itself. That stress may also be harmful. So I have chosen for myself a less restictive path with a higher (but still technically lowcarb ) approach that reduces that stress and the need to keep to strict diet plan and readings range. The OP is apparently following a keto diet that IMO is not actually necessary in their case, and is showing concern and hints of that associated stress. Pre diabetics should not be advised to go for keto diet IMHO. Low Carb? - yes go for it.

As requested
https://pubmed.ncbi.nlm.nih.gov/23372809/
https://www.healio.com/news/primary...of-lowcarb-lowfat-diet-impacts-mortality-risk
https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2759134
https://www.bluezones.com/2018/09/n...r-keto-diets-could-lead-to-shorter-lifespan/#

Note the latter link above is from a vegan supporting network and is potentially biassed.
 
I'd say you don't have bg problems but you are adjusting from having higher bgs to lower ones and to burning of fat for fuel rather than glucose from food. You can't have a true hypo (insulin over dose) unless you are taking blood sugar lowering meds or insulin itself (that doesn't include metformin and most other types of diabetic meds).
Your blood pressure is also lowering and you will be losing excess fluid as a result. Tha't's healthy but make sure you have adequate salt intake in case the feelings you describe are down to that.
Overall you may find fasting or one meal a day/intermittent fasting is not needed or desirable unless you were very insulin resistant and overweight but it sounds as if just lowering the carbs is working pretty well.
Next stage could be adding back in a few carbs to see what you can tolerate but that the longer you go on in ketosis the more you will adjust to these perfectly normal blood sugars. Type 1s get hypo feelings if they have previously been running high and I suspect its the adjustment process that is giving you symptoms or anxiety.
 
One aspect to consider is that current home testers have an error allowance or _/- 0.7 mmol/l at the levels you are measuring and would still be considered as 'accurate'. i.e. meeting their specification. Hypo's technically start when the bgl drops below 3.9 mmol/l. so your 3.2 could be the start of a minor hypo, but is possibly a 3.9 masquerading as a hypo. either way, a couple of jelly babies or a slice of bread will sort that out.
 
No blinkers. Just trying to stay relevant and on topic. Nor was I arguing the merits or problems of that or similar papers. Just that they were medication based not diet and thus you cannot draw the same conclusions as a result no matter what they are, especially when the report itself points out that the medication is the driving factor behind the detrimental effects seen.

Nor was I arguing for or against the long term benefits of ketosis as opposed to low carb. I don’t know the op’s goals, weight, desired weight loss or preferences. Only what she has said about bgl. Whether someone finds keto stressful is very individual and at least some of the stresses are easily avoidable with more detailed knowledge. Eg hydration, electrolytes, knowledgeable of false hypos etc

thanks for the links I’ll take a look and come back later with any observations.
 
One thing that may be relevant is that there are recorded events of hypoglycemia occurring post prandial for people who have had gastric interventions (i.e. band or bypass). Apparently this can manifest several years after the operation.

https://www.healio.com/news/endocri...a-a-serious-complication-of-bariatric-surgery

It is probably more associated with the Roux-Y technique, which is the most successful for reversing diabetes.
 

Hi Nicki - I also see blood glucose scores akin to yours, and I have done since soon after I git my blood sugars under control. I have never taken any medications for my diabetes.

Like you, the low scores are generally before a meal, and sometimes I'm rather hungry. I don't quite get the shivers or shakes, but do sometimes JUST WANT TO EAT!

I have never been one for snacking, so that isn't going to be my personal go-to solution to that situation.

If my meal is imminent, I'll stick it out, but if it is a but further off, I just have a cup of tea, with milk in it, and that just brings my sugars up the tiniest amount, and won't spoil my meal.

Provided you are not taking any medications to drive your blood sugars down (with pre-diabetes, I'd be astonished if you are), and are otherwise generally fit and healthy, you should be fine, but if you have concerns it is something to talk to your doctor or nurse about.

Well done I say.
 

I think the most important thing is to take notice of how your body is responding and adjusting to suit. You have only just started this journey, and it is very easy to go extreme at the beginning.
Consider increasing your carbs a little and give your body a chance to adapt. You can alway lower your carbs again later.
I also intermittent fast and my target carbs are 25g per day, which can be hard to maintain and can give me mild headaches. It has worked well for me,but I have also learnt that mixing it up a bit helps keep my metabolism guessing. This can be the occasional 18 to 24 hour fast or ‘high’ carb days of up to 100g. I would also aim for zero carb breakfasts. Treating it as a ‘carb fast’
 
If you're also taking some kind of med that increases your insulin that'll be the cause of the hypos. Essentially, it you are controlling your bs via diet and it's working, you probably don't need to be taking that med.
 
Thank you all for your replies.
I wanted to quote this because I have indeed had gastric surgery .. a gastric band. This was emptied at the start of the pandemic (due to discomfort) and not adjusted correctly (to this day). As a result I gained 50kg (yes kilos) in 18 months and I'm afraid I'm rather desperate to 'be myself' again .

This is where keto comes in. Believe it or not the diagnosis of pre-diabetes helped solve my years long question of why I would gain weight even if CICO was observed!

It's been a real eye opener. Finally I feel somewhat educated about the effect man-made carbs have on the body


For me, and probably many, keto js not sustainable long term, and I have these horrible hypo like symptoms occasionally (which without fail make me think I'm either having an anxiety attack or another stroke) so I plan to raise carbs a little some time in April.

Don't want my body getting used to non diabetic ranges if I am indeed diabetic (as I believe as I am nearer DT2 at 47.5 hba1c). I can forsee all sorts of complications including having to continue ultra low carb to avoid weight gain and having to put up with these horrible symptoms, or gaining weight and putting my BG up.

As others have pointed out, there's actually really no firm evidence that low carb can be good for you long term, as the science isn't in yet - it's too new a concept. It does, however, make sense to me as we haven't been processing our food for that long relative to how long we were around before relying on meat and natural sugars in fruit.

Thanks again. Great discussion for newbies.
 
NickiSanta said:
Don't want my body getting used to non diabetic ranges if I am indeed diabetic
Click to expand...
This makes absolutely no sense to me. Why would you want to maintain diabetic levels deliberately and unnecessarily risk complications?
NickiSanta said:
I can forsee all sorts of complications including having to continue ultra low carb to avoid weight gain and having to put up with these horrible symptoms, or gaining weight and putting my BG up.
Click to expand...
aren’t you facing exactly these choices whatever eating style you adopt? Manage it by making particular choices or risk blood glucose and weight gain? That’s not saying you should or shouldn’t choose to continue keto, just that the reality is choices do need to be made. It may be for you low carb without keto strikes the balance suitable for you. And for the record those horrible symptoms may well be temporary anyway not ongoing once you are adapted to the new levels or you find a better balance between carbs and symptoms and levels.
 
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