The Surge in Popularity of Continuous Glucose Monitors: Are They Necessary for Everyone?

Continuous glucose monitors (CGMs) have gained significant traction recently, becoming a popular tool in the realm of wearable health technology. These small devices, often resembling a patch the size of two stacked quarters, provide real-time insights into blood sugar levels, offering a potential means for individuals to manage their health proactively.

Health Secretary Robert F. Kennedy Jr. has emphasized the importance of these devices, stating that they empower users to take charge of their health decisions, including diet and physical activity. CGMs play a crucial role for individuals with diabetes, a condition affecting over 38 million Americans, which can lead to severe health complications if not properly managed.

However, the increasing popularity of CGMs among individuals without diabetes raises questions about their necessity and effectiveness. While some advocates, including prominent health figures, have marketed these devices to the general public, experts caution that the evidence supporting their use for those with normal blood sugar levels is limited.

According to Dr. Jody Dushay, an endocrinologist at Beth Israel Deaconess Medical Center, healthy individuals can effectively regulate their blood sugar levels without the assistance of a monitor. She points out that normal fluctuations in blood sugar occur after eating or engaging in physical activity, and relying on CGMs may lead to unnecessary anxiety over these natural changes. Furthermore, inaccuracies in readings can mislead users, potentially causing them to misconstrue their health status.

CGMs function by utilizing a tiny sensor that is inserted under the skin, typically on the upper arm or abdomen. This sensor continuously measures glucose levels in the interstitial fluid and transmits data to a mobile application or handheld device, allowing users to track how their food intake and activities affect their blood sugar levels.

For people without diabetes, a typical fasting blood glucose level ranges from 70 to 99 milligrams per deciliter. After consuming carbohydrates, it is normal for blood sugar levels to rise, sometimes exceeding 140 milligrams per deciliter shortly after a meal, before returning to baseline levels within a few hours.

Although CGMs have been available since the late 1990s for diabetes management, the last year marked a significant shift with the FDA's approval of the first over-the-counter models. This approval led to a surge in consumer interest, with many companies promoting these devices as tools for individualized health monitoring, often priced around $100 per month. For example, the weight-loss app Noom introduced a blood glucose tracking feature that has attracted numerous users.

While CGMs can be beneficial for those with diabetes and individuals at risk of developing the condition--such as those with obesity, prediabetes, or a family history of diabetes--their role for the general population remains unclear. Dr. Alaina Vidmar, a pediatric obesity specialist, notes that CGMs can help users understand their body's responses to different foods and activities, potentially leading to healthier choices.

Nevertheless, experts like Dr. David Kessler, a former FDA commissioner, caution against using these monitors purely out of curiosity. He highlights the lack of consensus on how to interpret data from CGMs for individuals without diabetes, as no established guidelines exist for optimal blood sugar levels in this population.

Before considering the use of a CGM, individuals should reflect on their motivations for wanting to wear one. Dr. Dushay encourages potential users to ask themselves what they hope to gain from the data provided by the monitor. Understanding the limitations and interpreting the information accurately is crucial for making informed health choices.