People who have diabetes—both type 1 and type 2—feel the heat more than people who don’t have diabetes. The reasons behind that include:1
- Diabetes complications, such as damage to blood vessels and nerves, can affect your sweat glands so your body can’t cool as effectively.
- People with diabetes get dehydrated (lose too much water from their bodies) more quickly.
- High temperatures can change how your body uses insulin.
It’s the Heat and the Humidity
Even when it doesn’t seem very hot outside, the combination of heat and humidity can be dangerous. When sweat evaporates on your skin, it removes heat and cools you. It’s harder to stay cool in high humidity because sweat can’t evaporate as well.1
Physical activity is key to managing diabetes, but don’t get active outdoors during the hottest part of the day or when the heat index is high. Get out early in the morning or in the evening when temperatures are lower, or go to an air-conditioned mall or gym to get active.1
How heat can affect your medication
Most types of insulin can tolerate temperatures up to 35 degrees Celsius. Exposing your supply to anything higher than this will make the medication quickly break down. Be careful and pay attention to any insulin you’re carrying with you in the heat.2
While it’s fine to store insulin and glucagon in the refrigerator, hot temperatures (as well as freezing temperatures) will cause the medications to degrade, making them ineffective and unusable. High temperatures can have a negative effect on other medications and diabetes management supplies too. Don’t forget about the weather’s effect on things like test strips and monitoring devices. When the mercury begins to rise, these items can change in their effectiveness.2
Tips for managing blood sugar
The summer season can throw off your routine, and possibly your diabetes management plan. Check your blood sugar more often to make sure it’s in your target range no matter what the summer brings. It’s especially important to recognize what
low blood sugar feels like and treat it as soon as possible.1 Follow these tips to help manage your diabetes while enjoying the outdoors:2
- Drink plenty of water. Staying hydrated is important for everyone during physical activity, and it’s especially critical if you have diabetes.
- Avoid becoming dehydrated. Carry small bottles of water or low-calorie electrolyte-replenishing sports drinks in a backpack or on a belt while you’re playing sports.
- Adjust your insulin as needed. Ask your provider or diabetes educator how you should adjust your insulin (and sometimes eating extra carbohydrates) before exercising. Typically, your first few doctor’s visits focus on urgent issues, such as getting diabetes under control. Ask about how to adjust your insulin so you can prepare to be physically active.
- Test your blood sugar levels frequently. Since hot temperatures can cause blood sugar levels to fluctuate, it’s a good idea to test more often. That way, you can take appropriate and immediate action to keep your levels stable. You should continue frequent monitoring for several hours after you’re done with your workout or other activity. That’s because the effects of activities on blood sugars usually last for a longer period of time.
- Take some snacks with you. Some snacks can serve as a meal replacement while others help prevent low blood sugar. Discuss possible options with your dietitian
- Protect your medication and supplies. Take proactive steps to protect your insulin, glucagon kit and other supplies before you head outdoors, regardless of the temperature. If you’re going away from your car for an extended period, you’ll need to take your supplies along with you. If you are on insulin pump, be sure to protect your insulin pump from high temperatures. Depending on the situation and how long your activity will be, you might simply need to monitor your glucose more often. In certain circumstances (if it’s extremely hot or you’re out for an extended amount of time) consider using a long-acting insulin temporarily along with meal insulin injection instead of an insulin pump.
1 Managing Diabetes in the Heat [Internet]. Centers for Disease Control and Prevention. 2021 [cited 4 July 2021]. Available from: https://www.cdc.gov/diabetes/library/features/manage-diabetes-heat.html
2 How to Manage Your Diabetes in Extreme Summer Heat [Internet]. Health Essentials from Cleveland Clinic. 2021 [cited 4 July 2021]. Available from: https://health.clevelandclinic.org/how-to-manage-your-diabetes-in-extreme-summer-heat/