Can Wildfire Smoke Affect Blood Sugar? What People with Diabetes Should Know…
Every summer, headlines remind us of the impact wildfires can have on communities across Canada. This year is no exception, with fires burning in parts of northern Ontario and smoke affecting air quality well beyond the fire zone.
Wildfire smoke doesn’t respect provincial boundaries. Changing winds can carry smoke hundreds—even thousands—of kilometres, meaning many people experience poor air quality without ever seeing a single flame.
If you are a person living with diabetes, you may notice something unexpected during these smoky days. Your blood sugar readings might seem a little higher than usual, even though you’re eating the same meals and following your normal routine.
So, what’s going on?
The short answer is yes—wildfire smoke and the conditions surrounding it can temporarily affect your diabetes management.
Your Body Sees Smoke as Stress
Wildfire smoke contains microscopic particles known as PM2.5, tiny enough to travel deep into your lungs and, in some cases, enter your bloodstream.
Your body doesn’t simply ignore these particles. Instead, it activates its natural stress response.
Stress hormones such as cortisol and adrenaline are released to help your body respond to a threat. Unfortunately, those same hormones can also make your body temporarily more resistant to insulin while encouraging your liver to release stored glucose into your bloodstream.
The result?
Even if you haven’t changed what you’re eating, your blood sugar may run a little higher than usual.
This doesn’t mean your diabetes is getting worse. It’s simply your body’s normal response to an environmental stressor.
Smoke Isn’t the Only Factor
Poor air quality often changes our daily routines.
Many people stay indoors when smoke levels rise, which usually means less walking, fewer outdoor activities, and more time sitting.
Since regular movement helps your muscles use glucose more efficiently, even a few less-active days can have a noticeable effect on blood sugar.
Stress Has a Bigger Impact Than We Think
Wildfires don’t have to be in your neighbourhood to affect you.
Watching the news, worrying about loved ones, disrupted sleep, or simply feeling anxious about what’s happening can all increase stress hormones that influence blood sugar.
If your glucose seems more unpredictable during these times, stress may be playing a larger role than you realize.
Don’t Forget About Hydration
Wildfires often occur during stretches of hot, dry weather.
When you’re dehydrated, glucose becomes more concentrated in your bloodstream. Higher blood sugar can also increase urination, making dehydration even worse.
Keeping a water bottle nearby and drinking regularly is one of the simplest ways to support your body during smoky conditions.
Your Medications and Devices Need Protection Too
Heat doesn’t just affect people—it can also affect diabetes supplies.
If you ever need to evacuate or spend extended time outdoors, remember:
- Insulin should never be left in a hot vehicle.
- Many injectable diabetes medications have recommended storage temperatures.
- Blood glucose meters, test strips, and CGMs can become less reliable if exposed to excessive heat.
- Sweat and heat may also loosen CGM sensors or cause adhesives to fail sooner than expected.
A little preparation can prevent a lot of frustration.
What You Can Do
When wildfire smoke affects your area:
- Check your local Air Quality Health Index (AQHI).
- Stay indoors when air quality is poor.
- Keep windows closed and use air conditioning on the recirculate setting if available.
- Consider using a HEPA air purifier if smoke is entering your home.
- Drink plenty of water.
- Continue monitoring your blood sugar, especially if readings seem different than usual.
- If you normally exercise outdoors, consider moving your workout indoors until air quality improves.
- Don’t panic if your numbers run a little higher for a few days.
The Measured Take
Living with diabetes means paying attention to more than what’s on your plate.
Sleep, stress, illness, exercise, weather—and yes, even the air we breathe—can all influence blood sugar.
The good news is that these changes are often temporary. Once air quality improves and life returns to its normal rhythm, blood sugar usually follows.
The next time wildfire smoke rolls into your community, remember that a slightly higher glucose reading isn’t necessarily a sign you’ve done something wrong. Sometimes it’s simply your body responding to the environment around you.
Understanding these influences can help you respond with confidence instead of concern.
After all, managing diabetes isn’t just about counting carbohydrates—it’s about understanding your body, adapting when life changes, and taking one measured step at a time.
Quick Tip 🍴
If your glucose runs a little higher during smoky days, resist the urge to make drastic changes to your medication or diet without first speaking with your healthcare provider. Focus on the basics: stay hydrated, keep moving indoors if possible, reduce your exposure to smoke, and continue monitoring your blood sugar.
