Continuous glucose monitors: New guidelines recommend expanding CGM use for people with diabetes

A continuous glucose monitor (CGM) is a small, wearable device that automatically estimates your blood glucose (sugar) level every few minutes, 24 hours a day. About the size of two stacked quarters, a CGM device is worn on the arm or belly. A tiny sensor inserted under the skin measures a proxy for blood sugar and wirelessly transmits the results to a smartphone or other device.

If you have diabetes, a CGM reduces the need for frequent finger-stick blood tests and alerts you if your blood sugar drops dangerously low or rises too high. Another big benefit: the real-time data provide helpful feedback about how your diet, exercise, and other habits affect your blood sugar.

Broader use, proven benefits

Initially, CGMs were recommended mainly for people who rely on insulin to manage their condition, which includes everyone with type 1 diabetes (the less common but more severe form) and a small percentage of people with type 2 diabetes. The new guidelines recommend CGMs for far more people with type 2 diabetes, including those who take any medication that lowers blood sugar and for those with newly diagnosed with type 2 diabetes, according to the American Diabetes Association’s 2026 Standards of Care in Diabetes.

“Among my patients with type 2 diabetes, it’s been obvious that CGMs have helped them achieve much better blood sugar control and lose more weight,” says Dr. Osama Hamdy, an associate professor of medicine at Harvard Medical School and director of the Obesity Clinical Program at the Joslin Diabetes Center. In turn, that weight loss has helped to lower their blood pressure and levels of harmful blood lipids, he adds. Recent findings confirm these trends (see “Better blood sugar tracking may help your heart”).

Using CGMs to your advantage

When counseling patients, dietitians at Joslin Diabetes Center use the glycemic index (a measure of how much a particular food spikes blood sugar) as a starting point and base their questions and advice on the patient’s CGM data, says Anna Bondy, a nutrition and diabetes educator at Joslin Diabetes Center. “Continuous glucose monitoring is the best way to determine your individual glycemic response to foods,” she says. For people with diabetes, the recommended blood glucose target is less than 180 milligrams per deciliter two hours after a meal. With a CGM, you can check if you’re meeting that target and see if specific foods are causing blood sugar spikes, she says.

“Bananas are a great example. After eating them, some people feel fine, but others notice their blood sugar rises and falls quickly and they feel terrible,” she says. They may want to opt for fruits with a lower glycemic index, such as blueberries, stone fruits, and citrus fruits. Another option is have your banana with some peanut butter, as the protein and fat in the peanut butter will slow the glycemic response, she adds.

“We encourage people to eat about the same amount of carbs at each meal, usually around 45 to 60 grams, which helps keep your blood sugar balanced throughout the day,” says Bondy. For example, if you have a salad with grilled chicken for lunch, include a serving of carbs. Add some garbanzo beans or whole grains (such as brown rice or farro) to the salad or on the side, or even end your meal with a banana, she suggests.

“Using a CGM gives people with diabetes an extra layer of accountability,” says Bondy. The readouts reveal how food and exercise affects their blood sugar in real time, enabling them to make healthier choices.

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