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Hot bath and blood sugar levels

We are an exceptional group. For most it lowers, but for a bunch of it it raises; I find it goes down quite quickly afterwards within 15 minutes or so.
I wish this forum automatically translated numbers into the American systems both for A1C and for glucose measurements.
 
Daniel 2 said:
I wish this forum automatically translated numbers into the American systems both for A1C and for glucose measurements.
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It's not going to happen anytime soon, there is a conversion calculator on site but I do not have a link, as I do need not need to convert mine as Australia uses the same system of testing blood as the UK.
 
Tipetoo said:
It's not going to happen anytime soon, there is a conversion calculator on site but I do not have a link, as I do need not need to convert mine as Australia uses the same system of testing blood as the UK.
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Multiply UK by 18 x mmol/L to get US values.
I'll post both if I use any in future. It's my habit to see UK and think US anyway.
Easy nos.
3.5=63, 4.0=72, 4.5=81, 5.0=90, 6.0=108, 7.0=126, 8.0=144
0.1=1.8(~2)
 
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Lotties said:
Multiply UK by 18 x mmol/L to get US values.
I'll post both if I use any in future. It's my habit to see UK and think US anyway.
Easy nos.
3.5=63, 4.0=72, 4.5=81, 5.0=90, 6.0=108, 7.0=126, 8.0=144
0.1=1.8(~2)
Click to expand...
I do not convert anything to minority measurements... :meh:
 
kenroar said:
I have the same problem. I take my reading before and after my shower and my blood sugars rise 50-60 mg/dL at that time. This is before I’ve had breakfast. I found your post by searching for the same thing. It must not be a common thing. This is independent of what I have to eat the night before. The diet the previous night had no bearing on the reading after the shower. I take my readings by scanning my LibreLink with my phone so test strips have no bearing either. I’ve eliminated all other variables so the act of taking a shower is the culprit.
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I get a spike on my Libre when I have a hot shower.
However I have put this down to the hot water affecting the Libre.
I haven't finger pricked before and after a hot shower to confirm that these are true readings.
I wonder if anyone has?
 
LittleGreyCat said:
I haven't finger pricked before and after a hot shower to confirm that these are true readings.
I wonder if anyone has?
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I have, and it's roughly the same before and after hot showers. I get the same thing if I sit in direct sunlight on very hot days in the summer on the libre, so my guess is it's a temperature error rather than a glucose spike from hot water.
 
I get a blip upwards from a hot morning shower, which may be influenced by my usual dawn phenomenon.

lovely relaxed hot bath or hot tub soaks always produce a blip downwards.

neither blip is particularly significant (usually less than 1mmol/L in either direction), and the effects have usually returned to starting point by the time I have dried and dressed.

saunas? Not interested in finding out :D
 
Its quite simple once you understand that insulin resistance (type II) is related to the cortisol hormone system in your body. Cortisol is the stress hormone, ANY type of stress will affect your glucose levels when you are type II with a strong insulin rtesistence factor, physiological (heat usually), psychological (fear, anger, frustration, depression worry) all affect your glucose level to one degree or other. In my casse is heat and driving a car, I worryh about it, I drive as if i am in combat, (fear/worry) which these days is not far short of the truth.When travelling in car in the back seats i have no adverse effect, fronts seats its the same as a hot bath. BTWE ifhey could easily measure cortisol levels and insulin this would become a known medical fact overnight. BTW this will not affect everyone the same. The worser yourm insulin resistance the worse the effect.
 
@LittleGreyCat
I get a spike on my Libre when I have a hot shower.
However I have put this down to the hot water affecting the Libre.
I haven't finger pricked before and after a hot shower to confirm that these are true readings.

I have verified using 2 different additional glucometers and in my case it is a real rise. Note: it usually drops off quickly after cooling down, much faster than after a meal. Indicating that it is in fact a Cortisol reduction (Cortisol has a very short half life in the body - it has to in order to do its job) so when you see rapid rises and falls (within 30-40 minutes) its almost certainly a Cortisol spike that is driving your glucose levels. Please also note that adrenaline can also do it but cortisol is the main cultprit which also is beihind the dawn phenomenon as your body starts manufacturing cortisol at that time to wake you up. Adrenaline will do it because it pumps up cortisol too. That is why exercise CAN raise glucose levels short term (minutes/hours) but lower them long term (weeks / months).
 
nasirali said:
Hi

I have been registered for some time but this is my first posting.

My name is Nasir and I am 77 years old. I was diagnosed accidentally in 1997 with type 2 diabetes. I am on Gliclazide tablets, 4 daily. I have no diabetic complications.

My question is rather unusual.

I am very fond of very hot (40-43 C). I usually have my bath before going to bed about 2100, about 2 hours after supper and it lasts for about 1 and a half hour. Usually I have a fairly high protein supper.

Now, the weird thing is that my blood sugar 2 hours after supper is in the region of 4-7 mmol/L. However, after the bath it frequently rises to 9-12 mmol/L.

I am a retired doctor and just cannot understand why a bath should raise my blood sugar.

I have searched the internet and found almost always that most people find that a bath reduces their blood sugar!

Can someone give me some idea what is happening?

Many thanks.
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Could be related to a drop in blood pressure.
 
SlyFox said:
@LittleGreyCat
I get a spike on my Libre when I have a hot shower.
However I have put this down to the hot water affecting the Libre.
I haven't finger pricked before and after a hot shower to confirm that these are true readings.

I have verified using 2 different additional glucometers and in my case it is a real rise. Note: it usually drops off quickly after cooling down, much faster than after a meal. Indicating that it is in fact a Cortisol reduction (Cortisol has a very short half life in the body - it has to in order to do its job) so when you see rapid rises and falls (within 30-40 minutes) its almost certainly a Cortisol spike that is driving your glucose levels. Please also note that adrenaline can also do it but cortisol is the main cultprit which also is beihind the dawn phenomenon as your body starts manufacturing cortisol at that time to wake you up. Adrenaline will do it because it pumps up cortisol too. That is why exercise CAN raise glucose levels short term (minutes/hours) but lower them long term (weeks / months).
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Could be cortisol, but what is it about hot bath or shower that triggers cortisol . This hormone is not ehe fight or flight hormone, but is an indication of chronic stress. Plausible explanation. But do we get same reaction to hot weather? Do our bgl levels rise in the summer compared to winter? I have not plotted anything like that in my history which is nearly 5 years of daily readings. No seansonal effect that I can observe.
 
Oldvatr said:
Could be cortisol, but what is it about hot bath or shower that triggers cortisol . This hormone is not ehe fight or flight hormone, but is an indication of chronic stress. Plausible explanation. But do we get same reaction to hot weather? Do our bgl levels rise in the summer compared to winter? I have not plotted anything like that in my history which is nearly 5 years of daily readings. No seansonal effect that I can observe.
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Maybe the sudden shock to the system of a difference in temperature? Like when you burn yourself on the iron or get a sudden scald from the kettle, you feel a rush of adrenaline?
 
KK123 said:
Maybe the sudden shock to the system of a difference in temperature? Like when you burn yourself on the iron or get a sudden scald from the kettle, you feel a rush of adrenaline?
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Thats because it hertz. Since when does a nice warm bath threaten us? Where is the stress? I presume that the testing comes after a lie in when the shock should have subsided. Maybe it is the cooling down after getting out that is doing it? I would have thought that this would have shown up in countries where saunas are regularly used, so again mystifying
 
I definitely see same. I have Dexcom. BS just went from 6.0 to 10.1 as I soaked in hot bath after driving home from gym
 
interesting discussion - I am not diabetic but my hba1c is rising and is borderline prediabetic as per the latest blood test. I am using Libre to see which food/activities are impacting my BG and how. I noticed that even with a 24 hour fast, my BG on Libre rises consistently from 4.8mmol to 6.4mmol and drops immediately after. Is this Libre sensor reading problem or is cortisol causing high BG levels?
 
aaq said:
interesting discussion - I am not diabetic but my hba1c is rising and is borderline prediabetic as per the latest blood test. I am using Libre to see which food/activities are impacting my BG and how. I noticed that even with a 24 hour fast, my BG on Libre rises consistently from 4.8mmol to 6.4mmol and drops immediately after. Is this Libre sensor reading problem or is cortisol causing high BG levels?
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Your body is correctly identifying the onset of starvation and has instructed your liver to take energy from that previously stored. In other words your fast is working. You are depleting excess fat.

They used to call it living off the fat of the land, but I prefer to think of it as living off the fat of the lard. It is actual fat from the stored lipids.
 
Oldvatr said:
Your body is correctly identifying the onset of starvation and has instructed your liver to take energy from that previously stored. In other words your fast is working. You are depleting excess fat.

They used to call it living off the fat of the land, but I prefer to think of it as living off the fat of the lard. It is actual fat from the stored lipids.
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Thanks for your response.

Sorry I noticed that I missed an important part of my post above. To clarify - I have been using Libre 2 for the last 7 days. I fasted only on 1 of those 7 days. However, the Libre is consistently showing high reading (6.4 mmol) after showering which drops to 4.8 mmol within minutes. So my point was fasting or not-fasting, rise in the Libre reading post-showering has been consistent. Initially, I thought it may be down to food etc but no matter what I eat or even when I fasted, Libre readings go up after showering and come back down pretty quickly. On the fast day rest of the time the BG reading is constant between 4.2 and 4.8 mmol. My BMI is 23.5.
 
I presume you are not removing the sensor when showering. so it may be affected by temperature or moisture. If it drops back again in minutes, then it is probably not glucose related as in liver dump or cotisol rush. I don't know if the Libre is sensitive to blood pressure but low BP may well alter the timing of the interstitial fluid motility which agian shows this is probably not related to actual glucose values. My guess is that it is moisture related.

Edit to add: Seems showering with the Libre is ok for up to 30 minutes. But that is in regards to the limpet used to glue the sensor, but no comments tregarding spikes have been reported in a thread on this forum discussing this matter. So I have no explanation.
 
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Oldvatr said:
I presume you are not removing the sensor when showering. so it may be affected by temperature or moisture. If it drops back again in minutes, then it is probably not glucose related as in liver dump or cotisol rush. I don't know if the Libre is sensitive to blood pressure but low BP may well alter the timing of the interstitial fluid motility which agian shows this is probably not related to actual glucose values. My guess is that it is moisture related.
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Yes, I keep the sensor on (didn't know it can be removed once installed).

Interestingly, the line chart on the Librelink app does not show the higher values despite the log book showing the higher readings. Also, the daily log on Liberview, although shows the reading, it shows it outside of the line chart (as per the image). So, looks like Libre charts are calibrating out those values.

I'll try a few other things to confirm this conclusion.

Libre.png
 
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