Summertime can bring extra challenges for people with diabetes. Research suggests that hot weather can lead to health issues for people with diabetes, making you more sensitive to high temperatures and humidity.

You may find it harder to keep your blood sugar levels under control, and you may be at increased risk for developing heat exhaustion.

So, when the weather heats up, it’s important to closely monitor your blood sugar levels and watch for possible symptoms that your body is not handling the heat very well. That way, you can take action before the situation becomes serious.

It’s not just that the hot weather can make you feel tired and sluggish. It can have some negative effects on how your diabetes affects your body. For example, people with diabetes tend to get dehydrated more quickly than people without diabetes. Signs of mild to moderate dehydration can include:

When dehydration becomes more severe, you may develop:

Some people even notice their sweat production drops off.

Dehydration can make your blood glucose levels rise. Then, you may develop a more frequent need to urinate, which compounds the problem.

You’re also more vulnerable to heat exhaustion because diabetes can damage your blood vessels and nerves, including the nerves in your sweat glands, so you may not be able to cool your body as efficiently as it needs.

Additionally, high temps can alter how your body uses insulin. Typically, if you’re exercising, it reduces your need for insulin. But hot weather can throw a wrench into that, and you may be at risk for both high and low blood glucose levels.

That’s a good incentive for discussing with a medical professional how to adjust your insulin, if need be, to account for your activity level and the weather.

In some places, it’s not just hot. It’s hot and humid at the same time. The extra moisture in the air can make the heat feel worse.

And here’s the challenge for people with diabetes: When it’s humid, your sweat doesn’t evaporate as well as it would under drier conditions. That makes it harder to stay cool, and that can make it harder for you to keep your blood glucose levels under control.

The Centers for Disease Control and Prevention suggests monitoring the heat index in your area, since that takes both temperature and humidity into account.

Managing your diabetes carefully is the best way to stay on top of the situation. Here are a few tips to help you do that and stay safe in the heat this summer:

  • Drink plenty of water. Avoiding dehydration is critical, so you’ll want to make sure you’re keeping up your fluid intake. But skip the sugar-sweetened beverages.
  • Dress for the weather. That means lightweight, loose-fitting clothes to help keep yourself cool, especially if you plan to spend time outside.
  • Avoid alcoholic beverages. Alcohol has a diuretic effect, so drinking alcoholic beverages will make you need to urinate more frequently, and you’ll wind up losing fluids.
  • Check your blood sugar levels frequently. This includes before and after activities like exercise, which affects your blood sugar levels regardless of the weather. Hot weather can make your blood glucose levels fluctuate even more than you might realize.
  • If you’re going to be outside, stay in the shade as much as possible. The heat index can be quite a bit higher in direct sunlight, so opt for the shade where it’s a little cooler.
  • Exercise indoors in air-conditioned spaces. You’ll be less vulnerable to heat and humidity. Or if you really love to exercise outside, fit in a workout in the early morning hours when it’s a little cooler.
  • Know your medications. Carefully read all the instructions for your medications so you’ll be aware of any warnings about heat.
  • Be prepared. Keep urine ketone tests on hand if you have type 1 diabetes and use insulin, since you may be at risk for developing a complication known as diabetic ketoacidosis.

How to keep your medicine and supplies safe in hot weather

The heat’s hard on your body, but it’s also hard on your diabetes supplies. They’re vulnerable to the hot summer weather. Here are a few tips for handling your diabetes medications and supplies:

  • Don’t leave your insulin pump, glucose meter, or other supplies in a hot car or even outside in the direct sun.
  • Keep test strips and other supplies in a cool location. A good rule of thumb: store them with your other equipment, and keep all of it out of the sun and heat.
  • Keep your insulin in a cooler if you’re traveling, but don’t pile ice packs directly on top of it.
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If you have diabetes, you’ll want to monitor yourself for the possible development of symptoms of heat exhaustion, as well as hypoglycemia and hyperglycemia. Sometimes the symptoms can be similar, so you may want to keep an eye out for a range of symptoms, and when in doubt, seek medical care.

Heat exhaustion

Your body can overheat in response to hot weather and develop a condition known as heat exhaustion. Symptoms tend to include:

  • drop in blood pressure
  • feeling faint
  • profuse sweating
  • dizziness
  • nausea
  • headache
  • weak and rapid pulse rate
  • muscle cramping
  • moist or cool skin even in high temperatures

While not as serious as heat stroke, heat exhaustion can pave the way for it, so don’t ignore these symptoms.


Hypoglycemia occurs when your blood sugar drops to abnormally low levels. Officially, it occurs when your blood glucose levels fall below 70 milligrams per deciliter (mg/dL).

Your risk for hypoglycemia increases in the summer because your metabolism tends to run higher in hot, humid weather, and you’re more likely to absorb more insulin.

When hypoglycemia develops, you may start feeling confused or develop blurred vision. Other symptoms include:

  • anxiousness
  • sweating
  • tremors
  • heart palpitations

In extreme cases, you may lose consciousness. Be sure to keep glucose tablets or another source of fast-acting carbohydrates on hand so you can take them right away if your blood sugar levels start to drop.


Hyperglycemia occurs when your blood glucose levels are too high. Your body either doesn’t have enough insulin or it can’t use the insulin it has effectively.

You have hyperglycemia if your blood sugar levels exceed 180 mg/dL after meals or hover above 130 mg/dL before you eat.

Feeling really thirsty or fatigued? Do you need to pee frequently? Those are common signs of hyperglycemia. Of course, excessive thirst and fatigue can also develop as a result of dehydration. But either way, you don’t want to brush them off. Check your blood sugar levels and make sure you’re also drinking enough fluids.

If you start developing signs that you are becoming dehydrated or having heat exhaustion, stop what you’re doing. Head indoors to a cool spot, drink some fluids to help you rehydrate, and check your blood sugar levels.

If your blood sugar levels have dropped below 70 mg/dL, remember the “15-15 rule,” suggests the American Diabetes Association. That is, consume 15 grams of carbs to raise your blood sugar levels and wait 15 minutes to test your levels again.

If your blood sugar levels are too high, quick-acting insulin can help counteract high blood sugar levels in many cases.

However, if your blood sugar levels are dangerously high, don’t wait. Have someone take you to the hospital. If you have low insulin levels, and very high blood sugar levels, you could go into diabetic ketoacidosis, which is a medical emergency.

Summer can be a marvelous time, but the heat and humidity can take their toll on people with diabetes.

It’s important to watch out for signs of dehydration and heat exhaustion, and keep close tabs on your blood glucose levels. Keep an ample supply of fluids, medications, and other supplies close by. That way you can reach for your medication, fast-acting carbohydrates, or other supplies as soon you need them.