Continuous glucose monitor: see how your blood sugar responds to real life

How Continuous Glucose Monitor works

A thin flexible filament sits just under the skin of your upper arm and measures glucose in the fluid between cells every few minutes. Readings go to an app on your phone. Over a wear period, the data shows your overnight baseline, how high and how long glucose rises after meals, and how quickly it returns to normal.

Who it’s for, and who it isn’t

What’s included

• Clinician screening to check a CGM is a good fit
• Sensor supply based on your plan
• Review of your glucose data alongside your labs, medicines and habits
• A written summary with practical next steps
• No membership fee

Possible side effects

• Skin redness, itching or irritation from the adhesive
• Mild pain or discomfort at insertion
• Rarely, local infection at the sensor site
• Anxiety about normal glucose rises after meals if data is over-interpreted

This isn’t a complete list. Your clinician reviews risks, interactions and warnings with you before prescribing. In an emergency, call 911.

What the evidence says

CGMs are well established in diabetes care, particularly for people using insulin. In March 2024 the FDA cleared the first over-the-counter CGM for adults who do not use insulin, including people without diabetes who want to see how diet and exercise affect blood sugar. Evidence that CGM use improves long-term health outcomes in people without diabetes is limited.

What a CGM shows that a lab test can't

An A1c tells you your average blood sugar over the past two to three months. A fasting glucose shows one moment after an overnight fast. Neither shows what happens after a bowl of pasta, a stressful meeting, a poor night of sleep or a brisk walk after dinner.

A CGM fills in that picture. Seeing your own patterns can make advice about meal order, fiber, protein, activity after eating and evening alcohol feel concrete rather than abstract.

What it cannot do

A CGM cannot diagnose diabetes or prediabetes. The CDC bases those diagnoses on lab tests: an A1c of 5.7% to 6.4%, or a fasting glucose of 100 to 125 mg/dL, indicates prediabetes, and higher values indicate diabetes. If your CGM data looks concerning, the next step is a confirmatory lab test.

Sensor readings are estimates from the fluid under the skin, not a blood draw. The National Institute of Diabetes and Digestive and Kidney Diseases advises checking with a finger-stick test if a reading doesn't match how you feel. The FDA also advises not making medical decisions from an over-the-counter CGM without talking to a health care provider.

Who gets the most out of a wear

The people most likely to benefit are those whose labs are heading the wrong way: an A1c in the high 5s, fasting glucose that has crept up, or a family history of type 2 diabetes. A short wear can make the risk tangible and show which changes help.

People on a GLP-1 medicine may also find it useful while they adjust how and what they eat. If your labs are normal and you feel well, a CGM is less likely to change anything, and your clinician may suggest saving the money.

Midlife changes a CGM can make visible

Glucose handling often shifts in your 40s and 50s. Muscle mass tends to decline unless you train for it, sleep gets lighter, and in women the hormone changes of perimenopause and menopause can coincide with rising waist size and insulin resistance. These changes are gradual, so they can be easy to miss until a lab result crosses a line.

A wear period can show, for example, that your overnight glucose runs higher after short sleep, or that the same breakfast causes a bigger rise than it used to. That kind of personal evidence often makes it easier to prioritize strength training, sleep and meal timing.

Over-the-counter versus clinician-guided

Since 2024, some CGMs have been available without a prescription for adults who don't use insulin. The FDA-cleared over-the-counter sensors provide readings in an app and can be worn for up to about two weeks each.

What HealifyMD adds is interpretation. A clinician screens you first, reads your data alongside your labs, medicines and history, and gives you a written summary of what it means and what to try next. Data without context can create worry about normal after-meal rises; context turns it into a plan.

What happens after your wear

When the wear ends, your clinician reviews the full data set, not just individual spikes. Key points include your overnight and fasting baseline, the size and length of rises after meals, and how quickly glucose comes back down. These are read together with your A1c, lipids, weight trend and medicines.

You receive a short written summary with two or three practical changes to try. If the pattern suggests your glucose may be in the prediabetes or diabetes range, your clinician will recommend confirmatory lab tests and discuss treatment options.

Wearing the sensor

Applying the sensor takes a minute with the built-in applicator, and most people feel little more than a quick press. It is designed to stay on through showers, sleep and exercise. Follow the device instructions about swimming, saunas and imaging scans such as MRI.

For the most useful data, live normally. Eat your usual meals, keep a short note of anything unusual, and try one or two deliberate experiments, such as a walk after dinner, to see the difference.

Price and plans

The CGM is $189 one-time for one 14-day sensor, with the clinician visit included. Pricing is confirmed during your eligibility review. CGMs used for wellness are generally not covered by insurance, and HealifyMD does not bill insurance. There is no membership fee.

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