Diabetes: know who should monitor glucose – 07/18/2023 – Health

Monitoring blood glucose levels was something that in the past was only done by diabetics. In recent years, however, glucose has become one of the most used biometric factors by people interested in optimizing their health. This is largely due to the increasing accessibility of an instrument called a continuous glucose sensor, or CGM.

CGMs monitor levels of glucose, the body’s main source of energy, in real time. A tiny, needle-like sensor is inserted into the skin and reads interstitial fluid glucose levels. That information is sent to a smartphone, where people can track it throughout their day.

The devices were developed more than 20 years ago for diabetics dependent on insulin injections. Today there are at least five companies selling apps and CGMs to people who don’t have diabetes, saying that knowing your glucose levels can help you lose weight and improve your health.

Abbot and Dexcom, the two biggest makers of CGMs, are also starting to invest in non-diabetic users. In its 2022 annual report, Abbott said it intends to broaden the application of CGMs to “use beyond diabetes”.

The company’s CGM sales totaled $4.3 billion in 2022, up more than 20% from 2021. Dexcom, which exclusively produces CGMs, also changed its mission to instead focus exclusively on diabetes, now return to to health in general. Its revenue is up nearly 20% in 2022.

Endocrinologists say CGMs are a must-have for diabetics who need to know when and how much insulin to receive. The sensors could also be useful in guiding diet and lifestyle changes for people with type 2 diabetes or who are at risk of developing it. This includes adults over age 45, people with a family history of diabetes, or people whose body mass index qualifies them as overweight.

For people outside these groups, there is little evidence that knowing how your glucose levels react to certain foods is a health advantage, in part because glucose spikes are usually not that big.

“I think most people, when they hear about CGMs, think it’s pretty cool,” commented Stanford University endocrinologist Sun Kim. But young, healthy people, he said, are generally bored because nothing is really changing.

Here are three things that are commonly said about the benefits of monitoring your glucose levels for non-diabetics and what the research indicates so far.

Help with weight loss

Firms that sell CGMs often say that the sensors help with weight loss. There is ongoing research to test whether this is true or not.

A company that sells CGMs says non-diabetic users of the device have seen modest weight loss (1.8 pounds in 12 weeks), but that’s comparable to the outcome of many dietary interventions, Kim said. When she compared the effects of CGMs and nutritional counseling in a small preliminary trial, she found no difference in terms of weight lost.

Theoretically, avoiding blood sugar spikes could promote more weight loss than just counting calories. When food is digested, glucose is released into the blood stream. This prompts the pancreas to secrete insulin, which helps cells take in glucose and use it for energy. Excess glucose is converted to fat, so the more glucose released during a meal, the more glucose can be stored as fat.

“This is one of the main mechanisms by which we store fat in our cells and gain weight,” said Eran Segal, a computational biologist at the Weizmann Institute of Science in Israel.

Author of a diet book based on that theory, Segal said the sensors provide those who use them with personalized information about how to avoid glucose spikes and lead to greater weight loss than general nutritional advice. Foods can have different effects on different people’s glucose levels, so without a CGM you are less likely to know which meals caused you to spike.

But other experts — including Michael Bergman, a professor of medicine at New York University Langone Health who studies diabetes prevention, and Kevin Hall, a senior fellow at the National Institute of Diabetes and Digestive and Kidney Diseases — said the idea that avoiding spikes in glucose can help with weight loss is controversial and “probably not correct”.

protect the heart

Another thing that is said in favor of sensors is that fluctuations in glucose levels in non-diabetic people can be detrimental to heart health. Therefore, using CGMs to identify (and thus prevent) glucose spikes may have cardiovascular benefits.

“But we don’t have studies that necessarily show us that this is correct,” said Jannifer Sherr, a pediatric endocrinologist at the Yale University School of Medicine.

For diabetics, persistently high glycemic indexes and large spikes in glucose are known to produce worse long-term outcomes, including heart disease and stroke.

Research has shown that higher glucose levels among non-diabetics are also linked to a higher risk of cardiovascular disease. But the studies reveal a correlation, not an unambiguous causal effect, said Robert Gabbay, chief scientific and medical officer of the American Diabetes Association. It is unclear whether lowering glycemic indexes actually leads to better health outcomes.

“That’s the missing piece,” he said.

prevent diabetes

The clearest potential benefit of CGMs is for people who are at risk of having diabetes. It is estimated that one in three American adults is pre-diabetic – that is, their fasting glycemic index is higher than the recommended (below 101 milligrams of glucose per deciliter of blood) but below the diabetes limit (126 for above). But the vast majority don’t know that. Research suggests that pre-diabetics have an increased risk of developing type 2 diabetes within the next five years.

CGMs are not officially used as a diagnostic tool, but elevated resting glucose levels or higher-than-normal spikes after meals are signs that something may not be right. The user can adopt behavioral changes to reduce their risk of developing diabetes, using the CGM data to learn which foods caused their glycemic index to rise and which behaviors keep it stable.

“It’s really important to identify individuals at a much earlier stage than we do today,” Bergman said. “I think using these devices is one way to do that.”

To improve your health, it’s not enough to know your glucose levels – you have to do something about it. Some experts, including Bergman and Gabbay, said real-time feedback on how different meals affect their glucose levels could motivate people to modify their diet. Others, like Kim, said that even with the sensors, it’s not easy to convince their patients to change their behavior.

For some people, it’s worth a try.

Most companies that sell CGMs charge between $300 and $400 for the device (including an off-label prescription for non-diabetics) and an app that helps users interpret their results.

For young, healthy people, there is no clear evidence that spikes in glucose (which are much lower than spikes in diabetics) are harmful to health. So while some people might be curious to see if manipulating this aspect of their biology changes how they feel, several experts said the potential benefits probably don’t justify the cost.

For people at risk of diabetes – a substantial portion of the population – the calculus is different. For that group, “I think CGMs are totally worth it,” Sherr said.

Translated by Clara Allain