If you’ve noticed your blood sugar creeping up during the colder months, you’re not alone. We recently ran a study looking at blood sugar readings from members in our Unified Care program between 2020 and 2025, and we found a clear seasonal pattern:
- Fasting blood sugar tends to run a little higher in winter (December–January).
- It dips in the spring, stays lowest in summer, and rises again in the fall.
The difference is small (about a 3% swing), but enough that you might notice changes in your numbers. After-meal readings, on the other hand, didn’t show much of a seasonal trend — likely because they depend more on what and when you eat.
Why Blood Sugar May Rise in Winter
- Less activity: Shorter days and colder temperatures can make us move less.
- Comfort foods: Heavier, carb-rich meals are common in the winter.
- Holiday treats: Celebrations often mean extra sweets.
- Stress and sleep: Less sunlight and more stress can affect hormones that raise blood sugar.
Tips to Keep Blood Sugar Lower
- Stay active indoors: Try short walks, light stretching, or chair exercises. Even 10 minutes helps.
- Choose balanced comfort foods: Add extra vegetables to soups and stews; choose broth-based soups instead of cream-based.
- Watch portions of carbs: Keep servings of bread, rice, and pasta smaller, and fill your plate with non-starchy vegetables.
- Stay hydrated: Cold weather can make you forget water, but dehydration can raise blood sugar.
- Keep a steady routine: Eating meals at the same times each day helps avoid spikes.
- Manage stress: Simple deep breathing, gentle movement, or a favorite hobby can help.
- Get natural light: Even a few minutes outdoors supports mood, sleep, and better blood sugar balance.
Bottom Line
If your blood sugar is running consistently higher than usual, or if you notice big spikes, reach out to your care team. They may need to adjust your plan.
Seasonal changes are real, but small. By staying active, choosing balanced meals, and keeping healthy routines, you can help keep your blood sugar lower all winter long.
