Blood Glucose & Your CGM

Blood Glucose & Why it Matters

We are going to be talking about the importance of blood glucose for metabolic health, and why you should pay attention to it.

You need glucose to fuel your body with energy. 

When you eat food, particularly carbohydrates, your body converts that food into glucose and it enters your blood. This is what we call “blood glucose.” So after a meal, your blood glucose will rise.

Your body does not want that glucose to accumulate in the blood; this can cause serious problems. Your body wants to clear out that glucose and put it to use. 

Let’s talk about two ways to do this:

• Muscles pull that glucose out of the blood for their use; the more you’re activating your muscles, the more glucose they’ll clear → this happens without relying on insulin!

• Insulin is released by the pancreas to clear out excess glucose from the blood, and direct it into the cells for energy.

  • The more glucose there is in the blood, that isn’t being used by the muscles or other organs (i.e., excess glucose), the more insulin needs to be released.

  • When insulin is released, it does a few things:

    • It stores the excess glucose as fat.

    • It blocks the feeling of being full and satisfied, which leads to more hunger.

  • Over time, if we’re constantly relying on insulin to clear that excess glucose, our bodies stop responding to insulin in the same way – this is “insulin resistance”.

With Type 1 Diabetes, your pancreas is unable to produce insulin to clear the blood glucose.

The real epidemic we see today is Type 2 Diabetes, which takes several years to develop. This is caused by chronically elevated blood glucose due to insulin resistance. 

Diabetes can lead to other very serious medical problems, and we want to do everything we can to avoid this.

Strategies to Control Blood Glucose

What can we do to avoid chronically elevated blood glucose levels and insulin resistance?

There are multiple strategies to control blood glucose levels:

• Nutrition

  • Avoid consuming simple carbs that don’t offer a lot of nutritional value and quickly raise blood glucose levels – for example, white bread, pastries.

  • Choose carbs that are high in fiber, which slows the digestion of glucose and avoid the large spikes that create a strong insulin response; for example, instead of orange juice, eat the whole orange which preserves the fiber. 

  • Similarly, try to eat protein and/or fat before, or with, carbs to slow glucose digestion.

• Exercise

  • Muscle activation will lower blood glucose directly, independent of insulin.

  • Exercise also makes you more insulin sensitive.

  • Additionally, building muscle will allow you to clear glucose more effectively.

• Sleep

  • Try to sleep 7-8 hours a night; <6 hours will increase insulin resistance, and also leads to downstream issues like lack of motivation to eat well and to exercise.

• Stress

  • Managing stress levels will help avoid excess cortisol, which causes elevated glucose levels.

Benchmark Glucose Assessments

There are two Benchmark assessments that help us learn about your glucose levels. 

• Blood Test: The primary metric comes from your blood test, giving us your HbA1C value, which is an estimation of your blood glucose levels over the past 3 months.

• CGM: 

  • The other tool we use is a Continuous Glucose Monitor (a CGM)

  • Your CGM has a microfilament that measures the glucose in your skin, and this provides an estimate of blood glucose, taking a reading every 5 minutes. 

    • This is really valuable because it gives us insight into how your blood glucose level varies throughout the day, and it helps you learn about the impact of your daily behaviors. You can start to see how specific foods affect you, because it is highly individualized, as well as the impact of sleep, stress, exercise, etc.

  • An important metric we get from the CGM is Glucose Variability. Not only do we want to avoid high levels of blood glucose overall, but we want to avoid really high, frequent, and/or prolonged spikes in glucose levels, as these can lead to problems.  

    • You can see this day to day. After you eat, your blood glucose rises, and that’s completely expected and normal. If you eat something like a piece of cake or an ice cream cone, you’ll see a big spike. Your body responds to that spike, releasing insulin to bring your glucose level back down. That drop in glucose can cause the feeling of a “crash,” where you feel low in energy and irritable. It also causes your body to feel hungry, causing you to eat more than you would have otherwise. 

How to Approach your CGM & General Targets

Here’s how we want you to approach your Benchmark CGM:

For the most part, follow your regular diet and routine; this will offer the most practical insight into your typical glucose levels.

Here are some suggestions to gain the most learning:

• Monitor the impact of how different foods affect you. 

  • Check your app in the 45 to 60 min. after consumption. Remember, that a spike after eating is normal, as long as your glucose level returns to your baseline level within 2 hours.

  • To gain the most insights, look at your app after:

    • Your go-to meals and snacks (test key foods individually when possible)

    • Your favorite sweet treat or a sugary drink

    • Carb-heavy food vs. protein-heavy vs. fatty

    • Higher-glycemic food alone vs. after a meal with protein and fat

• Monitor the impact of exercise. 

  • High-intensity exercise tends to raise your blood glucose level in the short-term; your body is releasing glucose into the blood to make it available for use. Lower-intensity exercise will help maintain more steady levels. If you go for a walk in the 45 minutes after a meal, you should see that your spike is lower than it would be with the same food, and no post-meal activity.

• Monitor the impact of stress. 

  • Stress signals to your body that you’re in fight or flight mode, so your body wants to make sure that energy is available to use, similar to the impact of intense exercise. With acute stress, like an argument, you may see a glucose spike. If you’re feeling low-grade stress on a regular basis, your average glucose levels will be elevated.

• Notice the impact of sleep. 

  • Studies show that those who get only 5-6 hours of sleep have elevated cortisol levels, and this leads to higher blood glucose levels, similar to the impact of stress. Make use of your wearable data to track this.

• Use the “Notes” feature in your Dexcom app 

  • Record notes (for example, what you ate, when) throughout the day. You’ll then be able to see how those behaviors correlated with the levels recorded on your app.

General Glucose Guidelines for Reference

To give you a sense of ranges for glucose metrics, we have the standard guidelines, as well as more aggressive targets that some experts point to for non-diabetic populations. Keep in mind that research is limited on the use of CGMs for non-diabetic populations, so we’re still learning a lot about what these should be.

• Average Glucose: 

  • Remember, what you see during the day will be higher than your average, because your levels will be lower overnight.

• Standard Guideline: 4.9 to 5.8 mmol/L

• Optimal target based on emerging research & expert opinion: 4.4 to 5.6 mmol/L

• Post-Meal Glucose Peak: 

  • Don’t be alarmed if you see levels slightly higher; you’ll want to take note of which foods cause these spikes.

• Standard Guideline: <7.8 mmol/L

• Optimal target based on emerging research & expert opinion: <6.1 mmol/L, with <1.7 mmol/L increase in the pre-meal baseline.