A blood sugar of 4mmol/l or under is considered a low blood sugar and requires immediate treatment. But many people can experience hypoglycemia at much higher numbers such as 5 -6mmol/l. This may suggest poor control of blood sugar levels, as the person begins to lose some of their hypo awareness. The same could be said of someone who maybe keeping their blood sugar levels too tight to achieve normal levels and may only feel a hypo at 2-3mmol/l or not at all.

People associate hypos or low blood sugars with those on insulin, but many people on certain types of medications for Type 2 diabetes i.e. sulphonyureas can experience hypo’s as well.

[pull_quote align=”left”]Hypoglycaemic events can be almost as damaging as a high blood sugar levels[/pull_quote]There is evidence from the American Diabetes Association to say that hypoglycemic events are almost as damaging as high blood sugar levels especially in the cardiovascular system [1]. After years of people been drilled about the dangers of complications from high blood sugar levels, we are now turning around in certain individuals and telling them to avoid the lows at all costs. Confusing isn’t it?


I see many people in my practices striving for HbA1c’s of 6% and under because thats what they believe is perfect control and will keep complications of diabetes at bay. I do get concerned, rather than a cause of celebration, scalesas to achieve this kind of level, you will have hypo’s, possibly too many. The other reason for a low HbA1c maybe due to the fact that a person could be anaemic. Teaching someone to rise their blood sugar levels is nearly harder than getting them to lower them!

The other reason I would be concerned about a low HbA1c is that I suspect someone is having hypos and is not feeling them. There is evidence to suggest that at least 50% of hypos go undetected especially when someone is asleep.



[pull_quote align=”left”]The hypos you feel by night are very different to the hypos you feel by day[/pull_quote]The hypos you feel at night are very different to the ones you feel by day. A hypo by day has all the classic symptoms of sweaty, dizzy, shaky, hungry, light headed, feeling fearful. By night you might not experience any of the symptoms. You might be restless in bed, having vivid dreams or night mares and/or sweating. Your partner might notice you groaning, snoring strangely etc. You should always have your meter by your bed, with fast acting carbs. If you wake in the middle of the night and can’t figure out why you have woken, check your blood sugar level. It might be that you are low and your body has woken you to tell you.

People underestimate the power of their own bodies and the unique ways it has of alerting you to problems. The issue I have is that people don’t take the time to listen to the signs their bodies have of letting them know there is a problem and this is really important, especially when you have diabetes. Listen to your body and if you are not sure whether you are having hypos or not at night, set your alarm for a few nights at 2am and take a blood sugar level. Also be aware waking with very high blood sugar levels may indicate a night time hypo as blood sugars will rebound to a high in reaction to a hypo.

Of course frequency of blood sugar testing is proven to help to reduce the risk of hypo’s in people with diabetes [2], but this is a very personal choice. Its not feasible for many people to be testing their blood sugars 8-10 times a day, not a mind your sore fingers!! But neither is it feasible for someone to go on their gut instinct when they think they are having a hypo. Symptoms of hypos can be similar to those of low/high blood pressure, or even hyperglycemia and if you are new to diabetes you might not be familiar with these warning signs. Also if you have had diabetes for some time and your control might not be the best, you need to test to confirm your hunch.

Hypos after meals can happen due to high fat meals and the delay that it causes in carbohydrates being absorbed and glucose being released into the blood stream. Alcohol taken without food can also cause hypoglycemia for up to 16 hours after consumption, depending on the quantity. The effects of exercise can also cause hypos for up to 17 hours post exercise, especially cardio or aerobic exercise. Extra blood sugar monitoring will need to be carried out to avoid the risk of hypos.

New driving regulations are going to also have a bearing as to how people deal with the whole issue of preventing or treating lows while driving with diabetes. Further info can be got from:


Swinging blood sugars from highs to lows, rebound hypos and hyper, can be very problematic for many people on insulin, and it takes time, effort and support to regulate these into a manageable pattern. It also helps to avoid the undetected or ‘hidden’ hypos that could be causing as much damage as the highs.


[1] http://care.diabetesjournals.org/content/36/Supplement_2/S264.full.pdf+html

[2] http://www.medscape.org/viewarticle/709187

One Thought to “Hidden Hypos”

  1. […] Basal insulin’s real handy work is seen with fasting blood sugars. If you are consistently waking with raised blood sugar levels too high or too low, then your basal insulin maybe an issue. For those who inject many people adjust by 4 units which in my opinion is too much, basal insulin needs to be adjusted by 2 units every 2-3 days before the desired result is achieved. Many people don’t like doing this, because it could take over a week to see the desired results, but in the long term it is worth it. When you adjust by more than 2 units, you end up correcting daytime blood sugars with bolus insulin, either by reducing or taking more, therefore you will never know what doses actually work for you. Just be mindful if you are waking with very high blood sugars, one of the reasons could be a hypo while you are asleep which has caused a rebound. For further info go to Hidden Hypos […]

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