Go to main content
Type 1
Type 2

Being Prepared: How Your Environment Can Affect Your Glucose

Did you know that something as seemingly unrelated to diabetes as getting a sunburn can actually have an effect on your glucose? Various environmental factors can affect your glucose levels and how you can effectively prepare to spend time outdoors.

Spending time outdoors, whether for exercise, travel, or just to get fresh air, is one of the best things you can do to maintain positive physical and mental health. Whether you love the beach, are an avid skier or hiker, or just want to spend time outside, knowing how your glucose is affected by your environment is crucial for staying safe and healthy. These factors can also pose challenges to storing your medical supplies and medicine – keeping them safe and effective.

Here we discuss three different environmental factors that can affect your glucose levels:

  • Outside temperature

  • Exposure to the sun’s UV rays

  • Being at high altitude

“People typically pay little attention to how the environment can affect their glucose, medications, and supplies,” said Dr. Kenneth Rodriguez, an endocrinology and diabetes specialist in Orlando, Florida. “There needs to be more awareness about these details and the simple fact that all these factors can affect glucose in the first place.”

Our bodies respond to our environment in different ways with changes in glucose levels. How then does temperatures, sunburns, or elevation changes affect your diabetes management and how you can always be prepared to enjoy outdoor activities?

Outside temperature

Managing your diabetes in hot or cold weather can present unique challenges. Not only can the surrounding temperature affect your glucose levels, but it can also damage your insulin and testing equipment. In extreme heat, your body produces excess sweat, which can lead to dehydration. Dehydration has the potential to cause higher glucose levels because there is less water in the blood stream and also can cause your body to release stress hormones (like cortisol) that tell your cells to release glucose. When you have high glucose levels, your body will then respond by urinating more, further contributing to this dangerous dehydration cycle. 

Exposure to high heat can also cause the temperature of your insulin to elevate and lose activity (making it less effective); this may change the color or texture of the insulin in some cases. In extreme cases, heat exposure could even damage your blood glucose meter (BGM), test strips, or other medications. If you plan to spend time outside on a hot day, be sure to store your supplies in a cooler, away from direct sunlight or extreme temperatures. Staying hydrated and checking your glucose levels regularly can also help you avoid fluctuations. 

On the other hand, cold weather can also have effects on your insulin and BGM. If your insulin freezes, it’s ruined, and extremely cold temperatures can cause your BGM to stop working. Being in colder temperatures and getting too cold can also increase your risk for hypoglycemia, as your body is using extra glucose in an attempt to stay warm (this is especially true if you are shivering, and your body is trying to generate heat). 

Not only that, but temperature can also affect your body’s ability to absorb insulin into the blood stream.

“Temperatures outside can affect when you should give yourself a bolus of insulin, in terms of how quickly your body will absorb it,” said Dr. Rodriguez. “When you are hot, your blood vessels near the surface of your skin expand, and you will absorb insulin much faster. When in cold temperatures, the opposite will occur, and bolus action can be delayed, potentially causing glucose to go higher temporarily [if you don’t time your dosing correctly].”

If you venture out into the cold, keep your insulin and glucose monitoring supplies close to your skin, or in a warm, insulated container. Additionally, wear gloves and warm your hands prior to checking your glucose to ensure that you have enough blood flow to get an accurate reading. 

Sun Exposure

For people with diabetes, the negative effects of a bad sunburn can be especially significant. When you get a serious sunburn, your body releases a hormone called cortisol – also known as the “stress” hormone – which can stimulate your liver to make glucose and increase insulin resistance.

The most obvious and effective way to avoid this? Apply sunscreen! Also, wear hats and clothes with UV resistance.

“I advise my patients to wear sunscreen, reapply every two hours, wear UV rated sunglasses, loose and light-colored clothing, and stay hydrated,” said Dr. Rodriguez. If you do get a bad burn, there are steps you can take to mitigate the effects, he explained, such as staying hydrated and treating it with aloe vera.

It is also important to be aware of any side effects of your medications that can cause increased skin sensitivity toward sunburn as well. According to Dr. Rodriguez, “Sulfonylureas [a glucose-lowering medication typically used for people with type 2 diabetes] can cause increased sensitivity to the sun, so people taking different medications should be aware about any warning labels or side effects.”

High Altitude

For those visiting high altitudes, and those who enjoy alpine activities like skiing or hiking, it’s important to know how your body responds to elevation. As anyone who has traveled to high altitude knows, altitude sickness can cause significant discomfort in the form of shortness of breath, nausea, exhaustion, and an increase in heart rate. 

These symptoms can also be caused by hypoglycemia, so be sure to check your glucose regularly to identify the source of these symptoms. This response to altitude can also result in dehydration and cortisol release, putting you at a higher risk for hyperglycemia. 

“In terms of symptoms, it is hard to tell the difference between altitude sickness and hypoglycemia,” said Dr. Rodriguez. “I recommend the same thing for when my patients encounter hot weather – check your glucose more frequently. If you feel any symptoms, check just in case to make sure [your glucose level] isn’t causing the problem.”

For those who have access to one, wearing a continuous glucose monitor (CGM) and getting real time glucose data can help. In addition, you may consider changing your CGM setting so that you are alerted earlier to concerning changes in your glucose.

In very extreme cases, cold weather and altitude may also affect the operation of insulin equipment. Though it is rare, as you travel to or from “High altitude, [it] may make some insulin pumps deliver more insulin [than intended by the user] due to the pressure change,” said Dr. Rodriguez. “Different pumps and meters will usually state how much altitude change they can withstand, so the user should take this information into account.” Check your devices user guide to see if there is an altitude limit.

One final note is that in order to circulate your blood and deliver oxygen to your body at high altitude, you may increase the work required for breathing. This can lead you to using more energy (and thus glucose), resulting in hypoglycemia. When traveling to a high-altitude region, be sure to stay hydrated and talk with your healthcare provider about any necessary insulin dosing adjustments that need to be made.

To learn more about managing diabetes in the outdoors, check out Justine Szafran’s article, “Off-the-Grid with Diabetes: Hiking and Backpacking in the Wilderness.” And for more information on staying safe during extreme situations or natural disasters where you may be exposed to extreme heat or cold, read “Be Prepared: Surviving Natural Disasters with Diabetes.”

Read about the other factors in Adam Brown’s, “42 Factors that Affect Blood Glucose,” here and download a free copy of his book, “Bright Spots and Landmines: The Diabetes Guide I Wish Someone Had Handed Me.”