Temperature sensitivity

I’m curious how others are when seasons change. The past couple of years, I have had to adjust things dramatically with temperature changes. Here in Australia, I believe (as do many indigenous people) that we have more than 4 seasons, although because I live in the small subtropical region on the east coast, we most likely have only 2 or 3 weather type changes over a year.
In Summer, insulin works quickly and my doses seem to run out faster. But in Winter, I am really struggling with hypos.

I remember that when I was at a party some considerable years ago, I was sitting on a couch around a fire outside, and I fell asleep. The fire went out and obviously my body used its reserves to keep me warm (alcohol certainly wouldn’t have helped), and I woke up to what must have been an extremely low hypo, as I couldn’t talk! Fortunately for me, I had a friend there that knew immediately what was going on and kept bringing me cups of warm water with buckets of sugar dissolved into it.

I have been finding that of late, hypos have increased overnight which I have attributed to me turning the heater off when I go to bed. My house is not that cold overnight (around 18°C), but I can’t contribute the 1-2am hypos to anything else, considering that my ‘usual’ hypo time is generally between 4-6am and can be explainable (I’m in the process of adjusting dose times in an attempt to stop my drops at that time of day).
So I was wondering, how sensitive is everyone else to temperature and temperature changes? How have those of you that are in the Northern Hemisphere gone with the high heats that some regions have been getting?


My hypos almost always are due to exercise, or taking too much bolus or taking it too early. I don’t seem to be effected by temperature. I used to notice I’d have a spike from a hot shower but that seems to have subsided. I have not noticed going low due to cooler or colder weather though (as you do) but perhaps the reaction would be similar to a shower - hot causes spikes while cool lowers (in your case).

We have been having temps here in the 100+ F range but I don’t notice it specifically effecting my BGs, other than higher BGs caused by lower activity due to the heat.


I’ve noticed the same thing with temperature, although here its seasonal from 35 C down to -30 C, obviously with heating and AC to compensate. I just adjust my basal to compensate. I wouldn’t say its as significant as intense exercise but still impacts my basal.

I have no scientific mechanism for why it happens, but I suspect its along the lines you describe. When I’m warm, no extra energy is needed to maintain a steady body temperature. When I’m cold, especially outside, I need to burn fuel to maintain body temp.


What Karl said is a good point, if your body is working to stay warm it can make a difference.

Other things can just be differences in overall activity. For example, if you spend winter chopping firewood or do different things than you do in the summer. Like if the summer is too hot and you mostly stay indoors and are less active.

Or differences in body weight can be a factor.


I’m much more insulin sensitive in the heat and warm months. Wintertime seems to add some extra insulin resistance.

I’ve seen some post on here about our bodies having a seasonal hormonal shift that contributes to alternating resistance/sensitivity.


The heat helps me adsorp the insulin, well, that’s what I think :wink: I can’t prove it, even empirically.

I suspect we all live in different temperature regimes. I live in Oregon, I go from 15F(-10C) in the winter to extremes of 120F(50C) in the summer. I don’t think that the temperature alone is the issue; the difference in sunlight contributes to a difference in my attitude to everything. I feel great in summer, bummed in winter.

To be honest I don’t think my ability to control my BG is better in either season; it may well be, but I can’t prove that. It should be because my skin is more set up to adsorp the subcutaneous insulin when it is hot, but I’m not sure that is enough to compensate for my own set of elephants in the capillary.


Cheers to everyone for your responses.
I was simply curious about how it might affect others.

I think as me and my D get older, I’m becoming more sensitive to subtle differences. It has also been a cooler winter where I live this year, so that may also play a part in what is going on with my body.

I guess the tell will be when it starts to warm up going into the warmer months and I need to add extra insulin to my regime.


@SBee You are right on the money about the insulin being quicker in the heat. As you warm up, the capillaries dilate to keep you cool. This will cause you to absorb the insulin faster.

My worst times of year are spring and fall. I live in Michigan in the United States, and our spring and fall temps can swing between 40F and 80F (4.5C and 26.6C) and this generally causes severe hypos in me. To add to the problems, our weathermen on the local news station are only about 50% accurate on good days so guessing what adjustments you need to make for the weather can be an interesting time.

surviving these weather conditions every year has been made much easier with glucose sensors.

I hope this helps, and you definitely not alone in this.


Thanks for your insight @MichaelS.

I would suggest checking out weather underground! They rely on people’s personal weather stations for the data. I find that weather forecasts are so generalised for regions, and because the ‘official’ weather stations tend to be located in airports, which with the exception of the inland airports, are generally right on the coastline (in Australia anyway). The difference between what happens there compared to where I am, can mean the difference of up to 5°C and the humidity can also change dramatically.
I also contribute, by having my own PWS. Then I always know for sure what is going on!

I find it fascinating to see the difference in my doses between the seasons. Being halfway through winter, I have substantially reduced my insulin requirements and I think I need to continue the reductions as I am still having far too many hypos.
So far, I have reduced my daily basal by 12u (I am MDI), and that seems like a considerable amount to me. I’m looking forward to seeing my endo soon, to see what his thoughts are!