Heat waves can make diabetes care more challenging in several ways. Here, we'll explain how extreme heat affects diabetes management and share practical tips to help you stay safe, protect your supplies, and maintain better blood sugar control during hot weather.
Quick Overview: How Heat Waves Affect Diabetes Management
- Heat waves can affect diabetes management by increasing the risk of dehydration, blood sugar fluctuations, and heat-related illnesses.
- Hot weather may cause both high and low blood sugar, depending on factors such as hydration, activity level, and how your body responds to insulin.
- Extreme heat can damage insulin, CGMs, and insulin pumps if they're exposed to temperatures outside the manufacturer's recommended range.
- Staying hydrated, monitoring your blood sugar more often, and protecting your diabetes supplies can help you manage your diabetes safely during a heat wave.
- Knowing the warning signs of dehydration and heat exhaustion can help you seek treatment early and prevent more serious complications.
How Heat Can Affect Blood Sugar
Hot weather can affect blood glucose in several different ways, and the impact isn't always the same from person to person. Some people notice their blood sugar runs higher during a heat wave, while others may experience more frequent episodes of low blood sugar. Although there are several factors that can contribute to this, it's also important to remember that everyone handles heat differently. Understanding how your body responds to high temperatures can help you make adjustments to your diabetes care routine and reduce the risk of complications. Still, a high heat index can have the following effects.
Heat Can Increase the Risk of High Blood Sugar
One of the biggest ways heat affects blood sugar is through dehydration. When you lose fluids through sweating and don't replace them, the amount of water in your bloodstream decreases and dehydration can contribute to higher blood glucose levels. High blood glucose can then increase urination, cause even more fluid loss and creating a cycle that's difficult to break. You may be at a greater risk of high blood sugar during a heat wave if you:
- Don't drink enough water throughout the day
- Spend extended periods outdoors in high temperatures
- Engage in high degrees of physical activity
- Experience vomiting or diarrhea in addition to heat exposure
- Already have elevated blood sugar levels before going outside
People with type 1 and type 2 diabetes feel the summer heat more and may be at increased risk for dehydration and heat-related illness than people who don't have diabetes. Therefore, it's important to work with your doctor to better implement tips to manage your diabetes in the heat, and what to do if you experience heat stress or symptoms of diabetes complications.
Heat Can Increase the Risk of Low Blood Sugar
Heat can also increase the risk of hypoglycemia (low blood sugar), particularly for people who use insulin or certain diabetes medications. This is because high temperatures can increase blood flow to the skin, which may cause insulin to be absorbed more quickly than usual. Faster insulin absorption can lower blood sugar sooner than expected.
In addition, many people are more physically active during the summer months. Even low-impact activities like walking, swimming, gardening, or spending time outdoors can further lower blood sugar, especially if you don't adjust your food intake or medication. Other situations that may increase your risk of low blood sugar include:
- Exercising outdoors during hot weather or in direct sunlight
- Using insulin during prolonged heat exposure and when combined with increased physical activity
- Skipping meals while remaining active
- Drinking alcohol in hot weather, which can contribute to dehydration and increase the risk of hypoglycemia particularly for people taking insulin or certain glucose-lowering medications.
Why Blood Sugar Responses Differ From Person to Person
There isn't a universal blood sugar response to hot weather. Some people consistently experience higher blood sugar during a heat wave, while others notice lower readings or greater fluctuations throughout the day. Your response depends on several individual factors, including:
- The type of diabetes you have
- Whether you use insulin or other glucose-lowering medications
- Your hydration status
- Your activity level
- How long you're exposed to the heat
- How effectively you manage your diabetes
Due to these differences, it's important to check your blood sugar more frequently during periods of extreme heat. Monitoring your levels can help you identify patterns, recognize unusual changes early, and make informed decisions throughout the day. However, if you experience persistent high or low blood sugar that doesn't improve, it's important to contact your doctor.
Other Ways that Heat Waves Can Affect Diabetes Management
People with diabetes may also be more susceptible to heat exhaustion and heat stroke, especially if blood sugar levels are inadequately controlled or dehydration develops. Some people with diabetes may also have nerve damage (diabetic neuropathy), which can reduce the efficiency of sweat glands, making it harder to cool down. This makes it more difficult to regulate body temperature and increases the risk of overheating. Therefore, it's important to try to stay cool and hydrated during heat waves, while also prioritizing diabetes care.
How Extreme Heat Can Affect Diabetes Supplies
High temperatures can also impact the performance of your diabetes supplies. Many diabetes medications and devices are designed to operate within specific temperature ranges, and exposure to excessive heat can reduce their accuracy or effectiveness. Therefore, it's important to take proactive steps to protect your supplies and ensure they continue working as intended during summer months.
Insulin Storage During a Heat Wave
Insulin is particularly sensitive to heat. If it gets too hot, it can lose its potency, making it less effective at controlling your blood sugar. While unopened insulin should generally be stored in the refrigerator until you're ready to use it, most opened insulin products can be kept at room temperature for a limited period, according to the manufacturer's instructions. However, they should never be exposed to extreme heat or direct sunlight. To help protect your insulin during a heat wave:
- Keep insulin out of direct sunlight and never leave it in a parked car
- Store it in a cool, shaded place whenever possible
- Use an insulated medication travel case if you'll be outdoors for an extended period
- Check the insulin for changes in appearance, such as clumping, discoloration, or cloudiness (unless it's normally cloudy), before using it
- If you think your insulin has overheated, contact your pharmacist or healthcare provider before continuing to use it
Continuous Glucose Monitors (CGMs) in Hot Weather
Continuous glucose monitors (CGMs) can also be affected by extreme heat. While the sensor itself is designed for everyday wear, extreme temperatures outside the manufacturer's recommended operating range may affect CGM performance. Heat and heavy sweating can also make it more difficult for the sensor adhesive to remain secure. To help keep your CGM working properly during a heat wave, try to avoid prolonged exposure to direct sunlight whenever possible.
You may also want to consider using adhesive patches or medical tape if sweating causes the sensor to loosen and always follow the manufacturer's instructions for securing or replacing it if it becomes loose, damaged, or stops providing reliable readings.
Insulin Pumps and Extreme Heat
Insulin pumps contain insulin that can also be affected by high temperatures. If the insulin inside the pump reservoir becomes too warm, it may lose effectiveness. Heat can also affect the pump's electronics, battery performance, or display if the device is exposed to excessive temperatures for prolonged periods.
To protect your insulin pump, it's important to follow the manufacturer's recommendations for safe operating temperatures and try to keep the pump covered or shaded when you're outside. If you find that your blood sugar becomes difficult to control, check the insulin reservoir and monitor your blood glucose more often. If you suspect that heat has affected your insulin or pump performance, follow the manufacturer's troubleshooting instructions and your diabetes care plan. Contact your healthcare provider or the pump manufacturer if you're unsure how to proceed.
Tips for Managing Diabetes During a Heat Wave
To help manage diabetes during heat waves or humid days, consider the following tips:
- Stay hydrated by drinking water regularly, even if you don't feel thirsty, to help prevent dehydration and support healthy blood sugar levels.
- Check your blood sugar more frequently.
- Store insulin and diabetes supplies properly; follow the manufacturer's recommended temperature guidelines.
- Avoid spending time outdoors during the hottest part of the day, typically between late morning and early evening, when temperatures are at their highest.
- Wear lightweight, loose-fitting, light-colored clothing to help your body stay cool and reduce the risk of overheating.
- Take breaks in air-conditioned or shaded areas if you're outside for extended periods.
- Adjust your exercise routine when necessary, such as working out early in the morning or later in the evening when temperatures are cooler.
- Carry water and a fast-acting source of glucose whenever you're away from home in case your blood sugar drops.
- Keep a close eye on your diabetes devices, including your CGM or insulin pump, to ensure they're functioning properly in hot weather.
- Watch for signs of dehydration, such as excessive thirst, dry mouth, dark urine, dizziness, or fatigue, and rehydrate promptly.
- Learn the signs of heat exhaustion, such as heavy sweating, weakness, dizziness, headache, or nausea. Confusion, loss of consciousness, or a very high body temperature may indicate heat stroke, which is a medical emergency requiring immediate medical attention.
- Create a heat emergency kit with extra insulin, medications, test strips, CGM sensors, pump supplies, snacks, water, and cooling packs in case you're away from home during a heat wave.
Explore Byram Healthcare's wide selection of diabetes management products and educational resources to help you stay safe and confidently manage your diabetes all summer long.
