Over the past year there has been a boom in “bio‑hacking” devices. Not content with smartwatches and heart‑rate straps, health enthusiasts are now strapping continuous glucose monitors (CGMs) to their arms in the hope of unlocking the secrets of metabolism. Social media adverts show runners checking blood sugar mid‑run, while influencers wear sensors during meetings and meals.
But do you really need to track your glucose if you don’t have diabetes? As someone who loves useful tech but hates useless noise, I decided to dig into the science behind this trend.
What Is a CGM, Exactly?
A continuous glucose monitor uses a tiny sensor (a thin filament) that sits under the skin on your arm or abdomen and measures glucose in the fluid between your cells. The sensor is held in place by an adhesive patch and sends data to a receiver or smartphone app. Older models required a prescription, but new over‑the‑counter devices are making it easier for anyone to buy a CGM. Originally designed for people with Type 1 or Type 2 diabetes to adjust insulin dosing and prevent dangerous highs and lows, they’ve become trendy among athletes and wellness‑seekers.
Why Healthy People Are Interested
If you’re already tracking steps and sleep, monitoring glucose sounds like the next logical step. Some of the reasons non‑diabetics are experimenting with CGMs include:
- Curiosity and control: Seeing your body’s response to different foods, workouts or stressors can feel empowering, even if you don’t change anything.
- Optimizing performance: Athletes hope to time carbohydrate intake to avoid energy crashes during long training sessions. Some companies claim “perfect glucose curves” boost focus and energy, though this hasn’t been proven.
- Detecting prediabetes: People with a family history of diabetes might use a CGM to see if they’re trending toward higher fasting glucose.
What the Research Actually Shows
Despite the hype, there is very little published evidence that CGMs improve health in people without diabetes. A Harvard Health review notes that among 153 non‑diabetic adults, 96 % of the time glucose levels were normal, and abnormal readings were often errors. The same review found no studies demonstrating health benefits from CGM use in healthy people.
Sports scientists echo that caution. Researchers at the University of the Sunshine Coast examined CGM use in healthy athletes and concluded there’s little evidence these pricey devices improve fueling strategies or performance. Studies exploring carbohydrate timing during endurance training have reported mixed results, and more research is needed before recommending CGMs as a coaching tool.
The Downsides and Risks
Before you slap a sensor on your arm, consider the drawbacks:
- Cost and waste: CGMs aren’t cheap; sensors typically last 10–14 days and cost about A$90–100 per fortnight or roughly $1,000 a year. Most health insurers don’t cover CGMs for people without diabetes.
- Comfort and reliability: Sensors can be knocked off during workouts, showers or daily chores. They may also cause skin irritation or adhesion issues.
- Information overload: Constant glucose data can lead to anxiety and obsessive eating behaviours. Experts warn that the deluge of numbers may prompt people to make unnecessary dietary changes or fear normal “spikes” after meals. Misinterpreting insignificant drops could even lead to extra snacking and weight gain.
- False sense of security: For healthy individuals, CGM readings rarely reveal actionable issues. You might spend money and mental energy chasing tiny fluctuations that aren’t clinically meaningful.
Are There Any Benefits for the Rest of Us?
There are scenarios where short‑term CGM use can be informative:
- Prediabetes or metabolic risk: If you have risk factors—such as a family history of diabetes, metabolic syndrome, or certain medications—wearing a CGM for a few weeks may help identify patterns that keep your blood sugar steadier.
- Understanding patterns: CGM data can show how different meals, meal timing or exercise types affect your glucose. For example, you might learn that a post‑meal walk blunts your glucose rise or that a high‑intensity workout temporarily spikes it.
- Working with a professional: Endocrinologists recommend using CGMs under medical supervision to interpret the data correctly. Athletes experimenting with CGMs should consult a sports dietitian to avoid misinterpretation.
Who Should (and Shouldn’t) Use a CGM
- People with Type 1 or Type 2 diabetes: CGMs are life‑changing for insulin management, hypoglycemia prevention and long‑term health. The devices are FDA‑approved for this group and often covered by insurance.
- Individuals with prediabetes or high risk: Short‑term use might provide insight into lifestyle adjustments. Discuss it with your doctor.
- Healthy, active adults with normal glucose: There’s no clear benefit. You’re better off focusing on proven habits like balanced nutrition, regular exercise, sufficient sleep and stress reduction. Save your money (and skin) unless new evidence emerges.
Final Thoughts: Don’t Let FOMO Drive Your Health Choices
It’s tempting to jump on every new health gadget, especially when friends or influencers rave about it. But remember the words of a Harvard physician: just because you can measure something doesn’t mean you should.
Rather than obsessing over real‑time glucose curves, most of us will see bigger gains from:
- Prioritizing whole foods over processed snacks.
- Incorporating Zone 2 cardio and strength training—check out my Zone 2 Training Guide for an easy starting point.
- Tracking your VO₂ max or heart‑rate variability to gauge fitness and recovery. Our free calculators on matisio.nl make this simple.
- Getting 7–9 hours of sleep and managing stress with mindfulness or nature walks.
Continuous glucose monitors are powerful tools for people who need them, but they’re not a magic bullet for the average gym‑goer. Be skeptical of marketing claims, consult professionals if you’re at risk, and keep your focus on the fundamentals. Your future self (and your wallet) will thank you.