The Effects Of Extreme Heat On Diabetes

Summers have gotten hotter in many cities across the U.S. over the past five decades, according to climate research group Climate Central, with extreme heat posing serious health risks related to the heat and reduced air quality.

The mild summers of previous generations are in the past, with record-breaking heat waves having deadly consequences. The forecasts mean the dog days of summer will get longer, as scientists project summer could last up to six months by the end of the century, impacting weather patterns, forestry and even water quality.

This spells trouble for those struggling to manage chronic health conditions in hot and humid conditions, such as diabetes, asthma, cardiovascular disease and mental health.

According to 2021 data by the CDC, approximately 38.4 million people (11.6% of the U.S. population) have diabetes, 8.7 million of whom were undiagnosed but met laboratory criteria for diabetes. According to the same report, diabetes was listed as the eighth leading cause of death in the United States, approximately 31 per 100,000 people.

Managing symptoms of diabetes isn’t easy, and the weather certainly doesn’t help matters with temperatures rising. In the guide below, we’ll be outlining the differences between type 1 and type 2 diabetes, how heat and humidity can affect the body, and tips to tackle the summer sun safely.

Type 1 Vs. Type 2 Diabetes

To understand the environmental factors that can affect those with diabetes, we’re breaking down the differences between the two types.

A few important definitions:

• Glucose: A type of sugar for energy that comes from food and the liver.
• Insulin: A hormone that moves glucose from blood to the cells. Without insulin, the glucose would stay in your blood and provide no energy.
• Pancreas: The organ that creates insulin.

Type 1 Diabetes: Autoimmune Disease

Type 1 diabetes is when the pancreas does not make insulin, because the body’s immune system attacks islet cells (the cells that make insulin in your pancreas). People with type 1 diabetes must take insulin because their body no longer produces the hormone.

Possible factors that trigger type 1 diabetes include genes, viruses, certain foods and chemicals, or other chronic conditions.

Type 2 Diabetes: Distinct Causes

About 1 in 10 Americans have diabetes, with most (between 90 to 95%) having type 2. While type 1 diabetes is due to an autoimmune attack, type 2 diabetes can develop due to a variety of factors, including:

• Overweight and obesity
• Insulin resistance
• Genetics
• Gestational diabetes developed during pregnancy

Symptoms Of Type 1 And Type 2 Diabetes

Type 1 and type 2 diabetes share a few similar symptoms, including extreme thirst, hunger, fatigue, headaches, blurry vision and increased urination.

Those with type 2 diabetes may also suffer from frequent infections, poor wound healing, numbness or tingling in hands and feet, and itching. Type 2 diabetes symptoms may take several years to develop.

How Does Heat Affect People With Diabetes?

Diabetes complications can be affected by the heat more than the average person. Below are just a few ways that extreme heat can play a more critical role in triggering the symptoms and complications of diabetes.

Sweating

Increased sweating can be caused by hyperglycemia (high blood sugar) or hypoglycemia (low blood sugar). For those who have consistently high blood sugar levels, the increased sweating may be related to nerve damage.

Decreased sweating, while less common, can occur with those who have diabetic neuropathy, which damages nerves and interferes with the ability of the sweat glands to function. According to the American Diabetes Association (ADA), around half of people with diabetes experience some form of nerve damage.

Dehydration

Hand in hand with sweating, dehydration may follow, especially when it’s humid. The heat index, also referred to as the apparent temperature, is what the temperature feels like to your body when relative humidity is combined with the air temperature. If you get too hot, you may sweat to try to cool down, but if it doesn’t evaporate due to high humidity, your body will continue to struggle to regulate its temperature.

The more you sweat, the more vital fluids and electrolytes (like salt, potassium and others) are lost. Symptoms of dehydration include dizziness, dry mouth, fatigue, headache and even fainting.

High Temperature Affects Insulin

Changes in temperature can affect blood sugar levels, especially during the warmer months. Dehydration can cause blood sugar to rise as the glucose in your blood becomes more concentrated. Hyperglycemia symptoms can include frequent urination and increased thirst and, if left untreated, could become life-threatening with signs including shortness of breath, fruity-smelling breath, nausea, vomiting and very dry mouth.

High temperatures can also cause blood vessels to dilate, increasing insulin absorption and leading to low blood sugar. Symptoms of low blood sugar (called hypoglycemia) may include feeling shaky, sweating and clamminess, confusion, fast heartbeat, nausea, hunger, sleepiness, headache, seizures and more.

Heat Also Affects Diabetes Medicine And Supplies

According to the CDC, heat can damage your blood sugar monitor, insulin pump and other equipment, so leaving them in a hot car or even in direct sunlight is strongly discouraged.

Heat can also damage insulin and test strips, so keeping your equipment at close to normal room temperatures when possible is necessary.

When insulin is damaged by heat, it can become cloudy, and the cloudy insulin will become grainy and stick to the side of the glass. Clear insulin that has been exposed to bright sunlight can sometimes take on a brownish color and should not be used. The meters and test strips shouldn’t be refrigerated, however, as cold temperatures can lead to misleading results.

Helpful Tips To Tackle Warm Weather

If staying indoors just isn’t on your to-do list over the summer when kids are out of school and you’ve been saving up your vacation time, it’s important to have a management plan in place when you have diabetes.

1. Check your blood sugar often: Check it before, during and after activities. It can impact how much insulin you actually need to use versus your regularly timed dosages.
2. Drink plenty of water: Even if you don’t feel thirsty, you could still be losing valuable fluids and electrolytes you need to avoid dehydration.
3. Avoid certain beverages: You don’t want to spike your blood sugar levels and lose even more water with certain drinks, such as alcohol, caffeinated beverages (like coffee and soda), and energy or sports drinks.
4. Bring snacks: Make sure you have the proper snacks or glucose tabs in case you end up with low blood sugar pressure.
5. Appropriate attire: Wear loose-fitting, light-colored clothing. Sun protection shirts that have UV protection are also a plus.
6. Sunscreen: If you can’t wear long sleeves, be sure to apply sunscreen and wear a hat when you're outside. Sunburn can raise your blood sugar levels.
7. Time of day: Consider going out earlier in the day or find enough shade that the temperature and humidity will be slightly lower.
8. Avoid walking barefoot: Don't go barefoot, especially on the beach or at the pool. Diabetics can have circulation and nerve receptor issues, so stepping on something sharp could cause cuts or punctures that can be difficult to treat. With decreased foot sensitivity, stepping on something sharp during the day may go unnoticed, so it’s important to check your feet nightly.
9. Air conditioning: Use your air conditioner or go to an air-conditioned building since a room fan may not cool you down enough. Be sure to check out our guide on portable air conditioners if you’re interested in shopping for one.

The Weather Company does not provide medical advice, diagnosis, or treatment. Talk with your doctor before starting any new medicine, supplement, weight loss or exercise regimen.

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