How Does a High Altitude Effect Type 2 Diabetes?

If you live with diabetes, you are likely already aware that traveling can throw off your diabetes care routine. What happens when you plan out a ski trip to the mountains and find yourself at a high altitude? You may be surprised to discover that altitude can affect your ability to be active and your blood sugar levels.

What is a high altitude?

A high altitude is considered to start around 8,000 feet above sea level. A very high altitude is between 12,000 to 18,000 feet, while an extremely high altitude is anything over 18,000 feet. For some context, Mount Kilimanjaro is 19,341 feet, and Mount Everest is 29,000 feet tall.¹

Many people coming from a close-to-sea-level location might start to feel the effects of altitude beginning at 5,000 feet. For example, someone coming from a coastal town in Southern California would likely feel a difference when they arrived in Denver, Colorado, which is at 5280 (a mile above sea level).

What happens at a high altitude?

High altitude has less oxygen. The higher you go, the less oxygen is present. Due to this, you may find yourself experiencing some unpleasant side effects if you are visiting a location that is high in elevation, such as:

• Low energy
• Fatigue
• Dizziness
• Headaches or migraines
• Shortness of breath and chest tightness
• Coordination issues

These are typical symptoms of acute altitude sickness. Although this is a rather mild condition, it can still affect your ability to go about your day and be active. Moderate and severe altitude sickness will result in the worsening of these listed symptoms.¹

Altitude sickness shares many symptoms with hypoglycemia, so it is important to check your blood sugar levels frequently to know what the source of your symptoms is. If you experience symptoms from type 2 diabetes or side effects from your medication, experiencing altitude sickness on top of this could put a damper on your trip.

High altitude and diabetes

Now that you know what high elevation entails let's review the relationship between type 2 diabetes and high altitudes.

Blood glucose meters

A small study found that high elevation can actually affect the performance of blood glucose meters. A group that was mountaineering on Mount Rainier in Washington State (with a total elevation of 14,410 feet) tested blood glucose meters at random elevations during their journey.

The researchers found that elevation does indeed affects glucometer precision. For every 1,000 feet in elevation, the glucometer underestimated blood sugar levels by 1 to 2 percent.²

Due to this, it is recommended that you do not calibrate a continuous glucose meter (CGM) during a flight. Some devices have an altitude limit, so be sure to check this.

Dehydration

Drinking enough water is very important for those who live with diabetes, especially at high elevations. Certain diabetes medications and experiencing nausea, vomiting, and diarrhea (common side effects of certain diabetes medications) can quickly lead to dehydration.

At high elevations, it is easier than you might think to become dehydrated, especially if you are being active and enjoying activities like skiing, snowboarding, hiking, and mountaineering.³

At high elevations, it is recommended that you drink between 3 to 4 quarts (96 to 128 fluid ounces) of water. If you are prone to dehydration due to your diabetes medications or symptoms, it will become crucial to drink plenty of water when you find yourself at high altitudes.¹

Hyperglycemia

Dehydration and the release of cortisol (a stress hormone) can occur at high altitudes, leading to a higher risk of hyperglycemia. Therefore, it is important to frequently check your blood sugar levels, stay hydrated, and be prepared if your blood sugar levels are too high.³

Be mindful of altitude

Diabetes self-care is essential all the time, especially at high altitudes. When you are traveling, it is vital to have a plan in place. Even for those who do not live with a chronic illness, high altitudes can cause many unpleasant symptoms.

If you are planning a ski trip or a getaway to the mountains, be sure to stay hydrated, check your numbers often, and have a plan if you are at risk for hypoglycemia or hyperglycemia.

What has been your experience at high altitude?