Master Your Metabolism by Using a CGM (Continuous Glucose Monitor)

Have you ever broken the law? Almost everyone has at one time or another. Sometimes it’s a little infraction, like driving 40 mph in a 35 mph zone. Or perhaps you crossed a street outside of the designated crosswalk. Here’s one I frequently observe: failure to signal when changing lanes while driving on a four-lane highway. What if you were notified every time you goofed up, whether in the car or at the dinner table? Would a CGM (continuous glucose monitor) device help you select the best foods for your body?

When Cravings Win: The Allure of Snacks and Sweets

Most people want to do the right thing, whether it’s obeying the speed limit, eating healthy food or flossing our teeth at least once a day. But many of us find it challenging to be consistent about such behaviors.

Let’s be honest. Our good intentions are frequently challenged when something really tasty shows up in our vicinity. For me, it’s pretzels. There is something about that salty crunch that is very satisfying. I have to admit that Peanut M&Ms are also incredibly tempting. And mint chocolate chip ice cream is also hard to pass up.

What’s your favorite snack food? Chocolate chip cookies or potato chips? Some people are suckers for Doritos while others crave Cheetos. Whatever you especially enjoy, it’s hard to pass up when it is readily available. What if you got a glucose report card after every chip, M&M or Frappuccino?

Would a CGM (Continuous Glucose Monitor) Make A Difference?

If we were continuously monitored, would our snacking change? When the navigation app on your smart phone alerts you to a speed check ahead, you probably slow down or at least look at your speedometer to make sure you are not over the limit, right?

Before you visit the dentist, you almost assuredly brush and floss your teeth, right? People who take music lessons of one sort or another almost always practice a bit more energetically prior to a lesson.

Are there devices that would help you be more thoughtful about food choices? It turns out that there is now an over-the-counter device called a continuous glucose monitor (abbreviated CGM) that keeps track of blood glucose levels. This just might make a difference about what and when you eat.

Diabetes and CGM Oversight:

For many years, people with diabetes had only one way to determine if their blood sugar was elevated. They used a test strip to check their urine to see if there was excessive glucose present.

In the 1970s, people with diabetes learned to prick their fingers and test a drop of blood directly. Because glucose levels fluctuate throughout the day, people with type 1 diabetes needed several finger sticks a day to calculate their insulin injections.

Eventually people with type 2 diabetes were also encouraged to monitor their blood sugar with finger sticks. Thus, they could assess the success of their medications and diet at home rather than waiting for a laboratory analysis and a doctor visit.

Continuous Glucose Monitoring:

The latest innovation is a continuous glucose monitor (CGM). This device, worn on the back of the arm, measures blood glucose throughout the day.

Many people with type 1 diabetes use a CGM connected to an insulin pump. This system automatically controls the amount of insulin injected based on the current blood sugar level. People with type 2 diabetes can monitor the effectiveness of their diet and exercise program and their medication.

A one-year outcomes study reported that (Diabetes, June 14, 2024, Supplement 1):

“Self-guided use of CGM by primary care patients with T2D [type 2 diabetes] for one year was associated with clinically meaningful improvements in A1C [hemoglobin A1c] and TIR [time in range].”

Over-The-Counter CGM Now Available:

Until recently, CGM devices were available only by prescription. Insurance pays for the device if the patient has been diagnosed with diabetes. Now that is changing.

The FDA recently cleared over-the-counter sale of continuous glucose monitors. Why, you might ask, would anyone want such a device if they did not have diabetes?

One explanation is that nearly 100 million Americans have prediabetes. That’s more than one third. The American Diabetes Association defines fasting glucose levels between 100 and 125 mg/dL as prediabetes.

A person who realizes that they are on the verge of developing type 2 diabetes can take steps to modify their diet and exercise. That way, they could avoid the serious health complications of this metabolic disorder.

Why Would a CGM make a difference?

Here’s where the continuous glucose monitor comes in. By providing consistent feedback, it allows a person to quickly assess the impact of food or beverages on blood sugar levels. That mid-morning snack of half a donut and a cappuccino could bump blood glucose out of range, but you might not realize that without a CGM.

An afternoon pick-me-up of chocolate chip cookies or a Coke and a bag of chips is also likely to bump sugar levels substantially. If you never see what’s happening internally, the temptation to indulge might be overwhelming. Watching your blood glucose levels shoot up within minutes of such a snack can be a potent reminder that what you put in your mouth matters. It is a notice that refined starches and sugars can mess up metabolism. Cookies, soft drinks or pretzels can elevate blood sugar surprisingly quickly.

Getting an instant report card in the form of a graph on a smart phone can be a great motivator to make better choices. Both the Stelo by Dexcom and the Lingo by Abbott are available for around $100 a month. Once people know how food and physical activity affect their blood sugar, they can begin to modify their behavior.

What Do You Think?

Have you ever used a CGM? Do you think it would affect your behavior? Please share your thoughts in the comment section below.

You may also wish to learn more about food choices that don’t raise blood sugar rapidly. You’ll find that information in our eGuide to Preventing & Treating Diabetes.