Intense fatigue, night sweats, unexplained weight gain and extreme hunger.
These were some of the sudden symptoms Lia Pinelli described to her doctor in August 2023. Since she was 46, her doctor said, it was likely perimenopause. But when the symptoms worsened, Pinelli knew something was wrong.
“It was so stressful trying to convince my doctor,” said Pinelli, of Buffalo, New York. “It felt like, ‘You’re not even listening to me.’”
Desperate for insight into her symptoms, Pinelli decided on her own to start wearing a continuous glucose monitor. The data from the medical device, typically prescribed to diabetics for monitoring blood sugar, showed she was experiencing episodes of hypoglycemia or low blood sugar. This finding finally got her doctor's attention, prompting further investigation into the confusing symptoms that may have been tied to autoimmune issues.
Continuous glucose monitors, or CGMs, have become more accessible since the Food and Drug Administration cleared them for over-the-counter use in March. Pinelli is part of a growing group of people without diabetes who use them as tracking tools to improve their health and wellness.
Some nutrition experts say a CGM can help people without diabetes be more aware of what they eat and how it affects their blood sugar. This could encourage them to choose healthier foods and stave off chronic disease, especially if they have a family history of metabolic disorders such as obesity or diabetes.
However, other experts say there's little data showing people without diabetes benefit from using CGMs. Some people with diabetes feel this wellness trend trivializes their experience, especially since many patients can't access these lifesaving devices due to the cost.
"It's been hard to get these devices and seeing it over the counter almost feels like a little slap in the face," said Mila Clarke, founder of the diabetes and nutrition blog Hangry Woman.
Can anyone buy a continuous glucose monitor? How much does does it cost?
People without diabetes can choose between the two continuous glucose monitors cleared by the FDA.
The agency approved the first CGM for over-the-counter use in March. Stelo, by Dexcom, was approved for anyone 18 and older who doesn’t use insulin, including nondiabetics and people with diabetes who only take oral medications.
One sensor is worn for 15 days. It’s about $99 to buy two sensors, to cover 30 days of wear time, or $89 for two sensors if they're purchased as a monthly subscription.
In the summer, the FDA approved two more devices that don't need a doctor's prescription. Lingo, created by Abbott, was designed for people 18 and older without diabetes. Libre Rio, by the same company, was approved for people with Type 2 diabetes who do not use insulin.
The Abbott options are only available online. The Lingo device costs $49 for a 14-day sensor or $89 monthly for two sensors.
Experts say these over-the-counter options have some limitations compared to prescription monitors. CGMs prescribed by medical professionals send alerts that notify users when they have high or low blood sugar, but that information is not provided in over-the-counter versions. The prescription-free ones also don't update readings as frequently as prescription devices.
Do CGMs improve wellness across the board?
Nutritionist Karen Kennedy uses CGM data in tandem with other tools to help her clients lose weight and improve overall health at her business, Real Food Matters, based in Vancouver, Washington.
Most of her clients don't have diabetes but they have other concerns: food cravings, headaches, pain and inflammation. Some have prediabetes or a family history of metabolic disorders. Kennedy recognizes the need for blood sugar control and said CGMs have helped.
"You get to peek under your hood and see what's going on in real time," she said. The fear of seeing a spike in their glucose forces clients to rethink their food choices.
Some research suggests that frequent blood sugar spikes in healthy individuals are associated with bad health outcomes, including cardiovascular disease. However, there's little data on what's considered a normal blood sugar range for someone without diabetes or on whether a CGM can improve health outcomes for this population.
Continuous glucose monitors:They're becoming more popular among the elite. What are they?
The Mayo Clinic says a blood sugar reading below 140 mg/dL is considered "normal." However, a study published in September by Boston University researchers found healthy individuals may spend up to three hours a day above that marker.
While there's an established blood sugar range for people with diabetes, the study suggests this may not apply to nondiabetic individuals, said Nicole Spartano, the study author and assistant professor of medicine at Boston University's medical school.
“We don’t necessarily know what is healthy in terms of these glucose monitor reports for someone who doesn’t have diabetes," she said. "It could be that it’s totally healthy to have spikes.”
Dr. Matthew Freeby, director of the Gonda Diabetes Center at the David Geffen University of California, Los Angeles School of Medicine, believes CGMs can play a role in improving the health of people without diabetes. But the medical community is still in a "learning phase."
"There's some potential but we need to learn more at this point," he said.
Response from the diabetes community
As more people opt into this wellness trend, many who suffer from diabetes still have trouble accessing CGMs due to inconsistent insurance coverage and out-of-pocket costs.
Diabetes doctors and patients say getting a CGM can take months, including wait times for an appointment, prior authorization and back-and-forth correspondence with insurance companies. Sometimes, insurance companies won't cover these costly devices if a diabetic patient isn't taking insulin.
Over-the-counter CGMs expand access to people with diabetes who aren't taking insulin, but approving them doesn't do anything to address the prohibitive cost, said Clarke from Hangry Woman, who has latent autoimmune diabetes, a form of Type 1 diabetes that develops slowly over time in adults. This is concerning because diabetes disproportionately impacts people in low-income communities, according to research from the American Diabetes Association.
Clarke is baffled by the device's popularity and wouldn't choose to wear one if she could help it. She said continuous glucose monitors may be trendy accessories for those without diabetes, but they're a lifesaving tool for her and others with this medical condition.
"If I didn't have to wear this device, if I didn't have to listen to the low glucose alarms at 3 a.m. and wake up to fix them, if I wasn't like a walking beeper all the time − I would love that," she said. "We can't just take it off, we can't just throw it away... It's part of our every day, to stay alive."
Jake Leach, Dexcom's executive vice president and chief operating officer, said the company's initial focus was to market and design its device for people with Type 2 diabetes not using insulin but adds Stelo "can help all people adopt healthier habits by better understanding the relationship between glucose levels and diet, exercise, sleep and medication."
Pam Nisevich Bede, head of nutrition at Lingo by Abbott, said her team is "passionate about the science" behind CGMs for nondiabetic individuals and prioritizes expanding access to all who need these devices.
"That's always on our mind because we've spent decades on diabetes research to make it more accessible and accurate for all patients and all clients," she said.
Clarke is hopeful the recent CGM trend will raise awareness, underscoring the importance of these devices for people with diabetes.
“I do hope the systems in place can really use the information they get from the general public using CGMs and apply that to people with diabetes,” she said. “These devices are our lifeline.”
(This story was updated to add new information.)
Adrianna Rodriguez can be reached at adrodriguez@usatoday.com.