Continuous Glucose Monitors (CGMs): Do You Really Need One If You Don't Have Diabetes?
- Daisy Habib, MS, RDN
- Jul 10
- 4 min read
If you've spent any time on social media lately, you've probably seen someone wearing a small sensor on the back of their arm while talking about "glucose hacks," "avoiding blood sugar spikes," or how they discovered that bananas, oatmeal, or even carrots are "bad" for their blood sugar.
Continuous glucose monitors (CGMs), a tool primarily used to help people manage diabetes, have become the latest wellness trend. Companies now market CGMs to healthy individuals with promises of optimizing metabolism, increasing energy, preventing disease, and helping people make "better" food choices.
As a registered dietitian, I have some thoughts about this trend. While CGMs are life-changing medical devices for people living with diabetes, their use among people without diabetes often creates unnecessary fear around food, reinforces diet culture, and can contribute to disordered eating behaviors.
What Is a Continuous Glucose Monitor?
A continuous glucose monitor is a small wearable device that measures glucose levels in the fluid just beneath the skin throughout the day and night. Rather than checking blood sugar with a finger stick, a CGM provides readings every few minutes, allowing users to see how glucose levels change in real time.
For individuals with type 1 diabetes, insulin-dependent type 2 diabetes, and some other medical conditions, CGMs are an invaluable tool. They help guide medication dosing, detect dangerous highs and lows, and improve overall diabetes management.
Blood Sugar Is Supposed to Rise After You Eat
One of the biggest misconceptions promoted on social media is that any rise in blood sugar after eating is harmful.
In reality, a glucose rise after eating is exactly how the body is designed to function.
When you eat foods containing carbohydrates—including fruit, grains, beans, dairy products, and many vegetables—your digestive system breaks those carbohydrates down into glucose.
As glucose enters the bloodstream:
Blood glucose naturally rises
Your pancreas releases insulin
Insulin helps move glucose into your body's cells
Your cells use that glucose for energy or store it for later use
Blood glucose gradually returns to baseline.
This entire process is a hallmark of human physiology—not a sign that something is wrong.
Are "Glucose Spikes" Dangerous?
The word "spike" has become a buzzword in wellness marketing, often implying that any noticeable increase in blood glucose is harmful. For people without diabetes, the research simply doesn't support this narrative.
Blood glucose fluctuations are influenced by many factors, including:
What you eat
How much you eat
Time of day
Sleep
Stress
Hormonal changes
Physical activity
Illness
These variations are not only expected—they're a sign that your body's regulatory systems are working.
Current evidence has not demonstrated that people need to eliminate normal post-meal glucose rises in order to improve health or prevent chronic disease.
Social Media Makes Normal Physiology Look Abnormal
One challenge with wearing a CGM without a medical reason is that you're suddenly exposed to hundreds of glucose readings every day.
It's easy to begin interpreting every fluctuation as a problem to solve.
You might notice that:
Oatmeal causes a larger glucose rise than eggs
A ripe banana raises your glucose more than berries
Eating lunch after a stressful meeting produces a different response than eating the same meal on vacation
None of these observations mean the food is unhealthy. Our bodies are dynamic systems, and glucose responses naturally vary from day to day—even when eating identical meals.
Focusing on individual glucose readings without understanding the bigger picture can lead people to assign moral value to foods that don't deserve it.
The Eating Disorder Concern
As an eating disorder dietitian, this is where my concern grows. Many people begin wearing CGMs simply out of curiosity.
Over time, however, some find themselves:
Avoiding foods that create larger glucose responses
Feeling guilty after seeing a "high" reading
Constantly checking their numbers throughout the day
Restricting carbohydrates unnecessarily
Becoming increasingly anxious around eating
This kind of hyper-vigilance can erode trust in internal body cues and encourage eating based on data rather than hunger, satisfaction, cultural preferences, or enjoyment.
For individuals with a history of dieting, disordered eating, or an eating disorder, CGMs used outside of medical necessity may reinforce obsessive thoughts about food and body control.
Glucose Regulation Is Only One Piece of Puzzle
A CGM cannot measure:
Nutrient adequacy
Mental health
Relationship with food
Satisfaction after eating
Social connection
Sleep quality
Joy
Stress
Overall quality of life
Nor can it tell you whether a meal was "good" or "bad." A meal shared with friends that causes a temporary rise in blood glucose can still be incredibly nourishing. Nutrition is about much more than one measurement.
Carbohydrates Are Not the Enemy
Many wellness influencers use CGM data to promote eating less carbohydrates.
Yet carbohydrates remain the body's preferred source of energy and are utilized for:
Brain function
Exercise performance
Hormone production
Digestive health (through fiber-rich carbohydrate foods)
Whole grains, fruit, beans, dairy products, potatoes, and many vegetables all contain carbohydrates—and all absolutely fit into a balanced eating pattern.
Restricting carbohydrates simply to flatten glucose curves is rarely necessary for people without diabetes and may have unintended physical and psychological consequences.
Should Someone Without Diabetes Wear a CGM?
For most healthy adults, there is currently little evidence that wearing a CGM improves long-term health outcomes.
Instead, many people simply become more aware of perfectly normal biological fluctuations.
If you have concerns about blood sugar, prediabetes, diabetes risk, or another medical condition, it's always appropriate to discuss those concerns with your healthcare provider. In those situations, glucose monitoring may be clinically indicated.
But if your motivation is driven by social media trends or the desire to achieve perfectly "flat" glucose lines, it may be worth asking a different question:
Is this helping me build trust in my body—or is it encouraging me to fear it?
Our bodies are designed to regulate blood sugar. Temporary increases after eating are not failures—they are signs of a functioning metabolic system.
