What constitutes a hypo?

I have been having discussions on another forum about what constitutes a hypo. In my belief, it’s a low blood sugar, which causes symptoms, such as sweating, shaking and confusion and impairs functioning.
I have met with an opposing view that it is a particular blood glucose level. 4mmol/l (I am in England).
I personally believe that without impairment, it’s not a hypo and hypo unawareness isn’t being hypo, without knowing it and without impairment.
My belief also meshes in with the idea that the sometimes called false hypo, when a person has hypo symptoms, but their BG isn’t very low, is a true hypo, characterised by normally having high blood sugar.
I don’t get hypos, since I’m only diet and metformin controlled, but I wondereed what the people on this group think about it

I have always considered a hypo as in when I have the shakes, confusion, weakness, etc. I would only call 3 or 4 a low, hyp for me is 3 and going down to 2. Some people don’t feel their hypos coming on so they may have a different take on things, but if your blds are down at 2 and you don’t feel it, it’s still a hypo IMO. You still need to treat the low, it’s just a hypo caught in time. I used to get the feeling of being low, with high blds, but never felt hypo.

Yeaa. personally I don’t feel a low until I’m down to the 2 marker. I can still fully function when my sugars at 3, which is a little concerning expecially when I’m out running etc… Buut I don’t really think about it to that extent. Same with me as Josephine. A hypo is below 3 for me and a low is in the 3 region. I prefer my levels to be at the lower end of the scale i.e 4 - 4.8 when I’m not really doing much during the day, and then when I know I’m going to be active to stop the lows I’ll eat a little more or take a little less insulin…

That’s nearer what I thought ladies! Becca, I note you are using insulin. Obviously it’s more of a problem with insulin than diet and/or Metformin.

I get hypo symtoms when my blood glucose level drops to 80’s or below. I know it doesn’t sound like a low number since I don’t take insulin, but I get all the same symtoms. Once I eat a 15 Carb Gram snack, it goes up to around 98-100 and I feel fine again.

“hypo unawareness isn’t being hypo, without knowing it and without impairment.”

Sorry, but WHAT?!!!

Let me just say, that as a T1, just because I may not be symptomatic AT ALL at say, 50, or even lower… that doesn’t remove the danger. It can be very dangerous… I can’t honestly tell that I’m impaired, and that’s really part of the problem - it messes with your judgment and the functioning if your brain (reaction time, thinking, etc). It’s why I test before I drive, EVERY time - because I just cannot tell. I have to keep testing every hour if I am driving a long distance because I can drop very low and not be aware of it. Yesterday in fact I was in the middle of a 4 hour drive, we pulled over to get some dinner, I had tested an hour before and was at 124, then I tested because we were going to eat, and I was 55, and had NO idea. It’s scary because 2 minutes before I had been behind the wheel.

Sometimes I don’t get typical hypo symptoms until I’m well into the 30’s, but that does not mean that I’m not impaired well before that, I just can’t see or feel it, but I would bet money that other people around me CAN tell. It’s almost like how someone who is drunk, on narcotics may not always be able to tell how impaired they are, but to anyone else it’s obvious from the slurred speech and slow reactions.

Sarah, I agree with you. I am hypo unaware, and I know for a fact that at 52 I am over the hill and going into the woods. I don’t shake, rattle and roll but my mind is not clear, and the confusion, even though I am not aware, means my mind is off track.

I drop over at about 35. I usually wake up in the ER and never even know how i got there. Geese it sounds so crazy to folks who still recognize lows, but it happens, and nope its not a good thing.

rick phillips

I’m with Sarah…WHAT?!? Not sure I really even understand the question here. You make it sound as if “a hypo” is a benign term for hypoglycemia and that without physical symptoms it doesn’t exist or isn’t real or dangerous…When your BG drops below 70 you are considered hypo whether you feel it or not. Chances are at this point there is at least a mental fog starting to creep in and left untreated the BG can continue to drop fast because we cannot tell when or at what level it will stop. Here’s a good article on what " a hypo" is. HYPOGLYCEMIA.

Your description of the hypo creeping down or BG dropping fast, Is only something that happens if you’ve taken medication that causes that. Anyone can have low blood sugar, with or without confusion. they don’t only happen to diabetics. Only if combined with Sugar lowering medication, will it continue to drop. A non-diabetic “auto-corrects” fast. that’s where most the danger lies, in diabetics, you don’t get the correction. I am T2 and use diet, exercise and a low dose of Metformin. I don’t have “chemically induced” hypos ever. In fact if I drop below 4 (72), the only awareness I have is that my legs feel a bit leaden. My thinking processe and reaction times are unaffected. I haven’t had hypo symptoms for years. since I stopped using Gliclazide.

When ones BG tends to be high all the time - it can happen that they feel low when going beyond a certain point. Eg when someone has high bg’s say 13 to 18 all the time they can feel low ie sweating, shaking when reaching 8 - This is a false low - normally one would recommend such a person not to eat so that his/her body gets use to the lower bg- because their body wants to go back to the comfort zone of say 13. I normaly suggest that one should only start treating a low below 3.2 mmol - true low.

And as someone already mentioned - when bg drops very fast one can also experience the symptoms of a low even if his/her bg is not below 4mmol/l.

People also experience different symptoms when in hypo. Some may only sweat while other starts shaking or have heavy legs. My son experience heavy legs, sweating, and he becomes very white around his mouth.

Firstly you have to look at the definition. Hypoglycemia literally means low blood sugar so your thoughts that it’s possible to have it with normal blood sugar levels doesn’t really make sense. I don’t agree with the 70/4 = low blood sugar rules because a person without diabetes who gets tested at 60/3.3 will be considered normal but under 60 is not normal and should be considered low and therefore hypoglycemia or hypo. It’s also been shown that blood sugar under 60, even if you feel fine, can cause permanent damage to the brain.

Hypo unawareness and false hypos are essentially the same principle, your body “learning.” If your body is used to having high blood sugar for long periods of time it will trigger your hypoglycemia reaction when it thinks it’s going low, even if technically your blood sugar is high or normal. If your body is used to running at a reasonably low or normal range and/or you have frequent dips in blood sugar, your body will not recognize a drop in blood sugar and will not trigger it’s hypoglycemic response. False hypos are not hypoglycemia because you can’t have normal or high blood sugar and low blood sugar at the same time. Likewise, hypo unawareness is a real hypo because of the same reason. You either have low blood sugar or you don’t. They also didn’t just pick numbers for the low blood sugar criteria out of a hat. They are based on thousands and thousands of blood tests that work out the average persons blood sugar ranges. the 70/4 is for diabetics only because in the days of insulin and sulfonylureas being the only treatments it was felt that having a higher goal for low blood sugar would help reduce the number of actual hypoglycemic attacks. It kind of just stuck.

However, you can believe what you want to believe but hopefully it doesn’t come back and cause you problems in the future because it is possible to get low blood sugar from metformin or even without any medication, with or without symptoms.

I searched for months and eventually found only 1 yes ONE study on normal non-diabetic blood sugar. David Mendosa found anohter one. It’s not something that has been done often. Probably because there’s no money in it.
the one I found was funded by Abbott Diabetes Care. I have mislaid the link, so I’ll have to hunt it up again. The average HbA1c in the study I found was 5.1%. I remember that and have set it as my target . I’m at 5.9% now.

A1c only tells part of the story. It’s possible to have a fantastic A1c but do it in a dangerous way. In fact, I have read more than one story of people with A1c’s in the 5% range or slightly below who die suddenly. The reason, they were having episodes of low blood sugar very often, often without symptoms.

I’m sure that’s true, but in my case, I never let my BG go over 6(108). And since I don’t use insulin or sulphonylureas, It never goes below 4(72 ) either. The danger lies with the use of insulin or insulin promoting medications. "Natural " BG control, by diet, is FAR safer.

However read this, it’s an eyeopener


Actually, this (and the symposium presentation) is a more appropriate page for this discussion. I’ve read most of her site and it does offer some fantastic information.


If you are in that 100% of the time then you have some other issue making your A1c as high as it is because it doesn’t quite add up, you should be hitting that 5.1 or maybe even lower. Since the A1c is not solely based on blood sugar it’s possible that something is making it higher in your case or your blood sugar is actually going higher than 4 but just not testing at that time.

I had realised that the numbers didn’t add up, but being in England under the care of the National Health Service, I only get 2Hb A1cs per year and I tightened up between the last 2 Also I don’t test often.I am not allowed Strips on the NHS for more than 2 tests per week As a non-insulin using T2. I fund my own, but I am a pensioner, I tend to use them only when I need to which is about 1 per day. I don’t get tests below 4 or above 6, when I do test. I am keeping tight to that at the moment, because I have weight issues too. I have lost about 40 pounds, but still need to get rid of as much again. I had hat last Hba1c in February and only really tightened up on the diet last summer. Due again in July, so I’m making sure it’s lower this time. I’m aiming for that 5.1%

I so agree with you Sarah - I am a type 2 myself and my better half is a type 1. We are having huge issues with Hypo unawareness. It is soo dangerous. I have looked all over for support forums for spouses, and supporters of diabetics, but have yet to find one that keeps up with the blog (maybe that is a hint to me to start one - just unsure how to do it). I am also a trauma nurse, so I understand what can happen. I think that many people do not understand that after your body spends an extended period of time in a hypo state ( meaning that you are low more often than anything else) you body adjusts to that. My fiance’ is completely unaware of anything when he is low, he does not sweat or shake anymore. I usually know by either him going into never never land and staring into space, or because he becomes extrememly agitated and will throw something or scream and yell at anyone around. This is tooooooo late to realize anything. Glucogon and I are very good friends and trying to get it in him has become a challenge. I wish people were as careful and aware as you are. You seem to be a great voice on Diabetes!

Thanks for that!!

I agree, the only A1c’s I’ve ever had in the 5 range were the result of multiple lows during the night… I would go low and just not wake up… so I had no idea it was happening. For me it wasn’t a good thing, I’d wake up feeling completely and utterly drained.

For me I was going VERY low… like in the 40’s and 50’s and staying there for very long stretches. My endo actually put me on a 3 day CGMS (this was 4 years ago) to identify it, because as she put it “with your meter average, your a1c doesn’t make sense”. She was right… it was probably close to a full percent lower than expected. I had NO IDEA it was happening… I knew I felt horrible after I got up in the mornings, but the #'s I saw didn’t reflect what was happening (and I’d only occationally wake with a low - not often enough to see a true pattern). I prefer to have my fastings around the 80-90 range, and I’d normally wake up there, but that wasn’t where I was all night long. The only reason my fasting #'s did come up is I have a pretty strong dawn phenomenon.

Part of the problem with T1 is that the function of the alpha cells (which produce glucagon) is often impaired, even though those cells themselves may not be damaged - our bodies just don’t react to lows the same way a “normal” person (or even T2 diabetic) would… so many of us simply don’t have the ability to recover from a moderately low blood sugar before it becomes a serious issue. I know that for me, a serious low (30’s) often results in rebound highs that can last the better part of a day - it’s like my body won’t release any glucagon on it’s own in any amount that would be helpful, and then just goes overboard.

I would definitely consider myself low if I were below 70 (don’t usually get symptoms till the 50’s) & I would treat it - if I tested & it was in the 70’s I would take into account the amount of insulin I had left on board (I use a pump) and my recent physical activity to see if I thought I was in danger of going lower. The value of CGMS is that it will catch lows before they actually happen - if I am with my husband or kids they will recognize a low before I do - I either start becoming incoherent or get stubborn and bitchy (though I did have one recently where I got silly instead - which was kind of nice). The bad thing about CGMS for me is that I don’t wake up when it gives a low BS alarm while I am sleeping - I don’t feel the vibrate or hear the sound - if someone is awake near me they hear it before I do!

Hi Sarah

Have the same experience with “bad” lows. I will get a rebound high about 3 or 4 hours after the low and then sometimes ping back and forth for the next12 hours. So frustrating!