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New CGM wearer, is this typical dawn phenomenon?

EmilyMay11

Active Member
Hi, applied my Libre 2 sensor for the first time last night before bed, I’ve read about dawn phenomenon and have done some finger prick readings while waking/ mid morning but never with this level of constant monitoring. Is this typical dawn phenomenon. It’s 08:55 and I seem to be sitting at constantly around 6 and have done for the past 45 mins ish.
Is there a way to stop this without medication or is it normal? My log book shows it more quickly if you can see over the dots. I’ve gone too excited with scanning, ha.
 

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I would say looking at that, it's a classic example, and very normal. with prolonged good control, your body will adjust to realise that you don't need to reach as high a level. You could try experimenting with eating a small amount of protein, just a mouthful, which may stop it, but don't worry if it doesn't. It's just normal life.
 
First, a few warnings.

Be careful of reading too much from one single day and graph. The libre is probably most useful for spotting trends, but you might find another days graph is completely different.
Don't automatically believe what you are told applies to you (including what I tell you). Your diabetics and hence your experience may be significantly different from mine.

Haven't said that, this is my guess.

Looking at your graph and assuming you were resting during that time and not eating. I would see four stages.


1) Between 1am and 3am. Relatively steady between 6 and 7 mmol/l
2) Between 4am and 5am. Sharp fall from 7 mmol/l to 4 mmol/l and then sharp rise back up to 7 mmol/l
3) Between 5am and 6am. Slower rise by 7mmol/l to 10 mmol/l
4) Between 6am and 9am. Slower fall from 10mmol/l to 6 mmol/l

Stage 1 is normal.

Stage 2. This looks to me like a compression low where you are lying on the sensor and it is reporting false (lower) values until you stop lying on it.

Stage 3. This looks like what I would expect from dawn phenomenon, although much more pronounced than I have ever experienced.

Stage 4. Not sure. Judging by the number of scans, you were awake during this time, but unless you got up at 6am and hence started burning extra glucose I would not expect your blood sugar to reduce that much.

> Is there a way to stop this without medication

Sometimes not even medication can stop it. If it is a problem then you may be able to minimise the phenomenon and the usual recommendation is to try to reduce carbs the previous night or else try to burn off extra glucose. This may be by avoiding carbs at night, eating a lower carb evening meal, eating your evening meal earlier or going for a walk after your evening meal.

But if stage 4 is normal for you and your blood sugar does fall, I would not think that you have a problem (Again just my opinion).
 
Aside from everything already said, I find the libre sensors are not reliable in the first 24 - 48 hours. In my case they read low but others find they read high. Some people place the sensor on their arm and don’t activate it for atleast 24hours.
 
Hi, applied my Libre 2 sensor for the first time last night before bed, I’ve read about dawn phenomenon and have done some finger prick readings while waking/ mid morning but never with this level of constant monitoring. Is this typical dawn phenomenon. It’s 08:55 and I seem to be sitting at constantly around 6 and have done for the past 45 mins ish.
Is there a way to stop this without medication or is it normal? My log book shows it more quickly if you can see over the dots. I’ve gone too excited with scanning, ha.
Might be. You've one day's data there - I'd want to see a bit more before reaching a conclusion. It is possibly a CGM artefact as well, particularly if you don't notice any effects from going low - although 4+ is not hypo territory.

It does look similar to what I have seen using a CGM - a drop into very low numbers sometime in the early morning, then a steady climb. I go lower and don't rise as high. My drop is accompanied by nightmares/vivid dreams and extremely heavy sweating, coinciding neatly with the low point. I can stop the steady rise "dawn phenomenon" bit with three almonds - my liver seems to accept I've got food and stops making glucose. I just wish I could do something about the drop.

"Dawn phenomenon" seems to be a perfectly normal thing and is reported by non-diabetic people who've been using a CGM.
 
Main thing here is - "don't panic"

For the obvious reason, but also because stress hormones are no help either...

I personally think that the first applied sensor is best thought of as a trial run - use it to learn a little about what the sensor does. After a few months, you will also be much more familiar with the fact that no two sensors are exactly the same..

beyond that, the key benefit of GCM is that it will give you information about what your body is doing, not generalised advice, or anyone else's opinion of what you should be seeing based on their experience..

There are generalisations that can usefully be made, but the definite benefit is that you will see what your own body is doing, and will start to make sense of it based on where you are on your own journey.

As for the Dawn Phenomenon... it's pretty complicated when you get right down to the details, but if you understand that there are lots of things going on to prepare you for the day, and in the same way that Diabetes (T2) is one of the end points of Insulin Resistance, you may find that your reaction to the various hormones that set you up for the day, change as you become more sensitive to them.

For me ... it took months for my "morning spike" to settle down, but each of us is different, it usually is not something that needs to be 'stopped' with any medication. In many ways - you should see something of a raise of blood glucose in the morning, but lots of things come in to play; levels of stress, sleep quality and regularity etc..

Definitely do not worry about the result of the first day...
 
@EmilyMay11 looking at your DP rise it looks to me like your pancreas wasn’t able to bring your Liver’s morning dump down. This can be due to a compromised First Phase Insulin Response coupled with your insulin resistance . It could be you had something very carby in the evening. Which ever, your pancreas was unable to produce enough insulin to cover that dump . Most people, none diabetics and diabetics alike, their livers dump first thing in the morning. These liver dumps are orchestrated by your circadian rhythms, your inner clock if you will, in preparation for activity. In none diabetics, these rises are quickly brought down, usually by their first phase insulin response. In a none diabetic, this first phase is strong, and it stops that spike. This initial wave of insulin is drawn from a small reservoir of insulin. It quickly runs out and if it doesn't bring your blood sugars down, your second phase insulin response kicks in. You can see that on your first graph. Two peaks, the first peak, just before 6am I am thinking is your weak response to your liver dump, then when that didn’t bring your blood sugars down your body started producing insulin which is your second phase insulin response. This second phase insulin production continues until your blood sugars return to homeostasis. Which for you was around 8:30 am. This is assuming you didn’t eat.

There is a degree of error in the Libre CGM once the reading go over 10 - 12 mmol/ls. You would need to confirm your actual readings with a finger prick. It wouldn’t alter the graph pattern, but the readings maybe lower. I find that the Libre can exaggerate the readings once you go over or under the ‘normal’ blood sugar range.

My DP can go up to around 10. If I do a lot of exercise the previous day it’s lower. Eating less carbs in the evening helps as your body doesn’t have a chance to burn those carbs off. Skeletal muscles consume 70% of your carb intake so it makes a difference.
 
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