Glucose monitors, recommended for use by diabetics, are increasingly popular among lifestyle content creators who claim they can help non-diabetics stay healthy. But nutrition experts say it is normal to experience an increase in blood sugar after eating and medical professionals warn social media posts offering tips on controlling “spikes” may do more harm than good.
“I tested Chick-fil-A on my continuous glucose monitor and it took my blood sugar to the moon. I was absolutely shocked how many people in the comment section thought it was normal. For the record, I am not diabetic, I am very fit and healthy,” says Jason Wittrock, who goes by @bloodsugarking on TikTok, in a May 24, 2022 video viewed 3.4 million times.
Wittrock, a fitness content creator who claims to “fight a war” against obesity, then says eggs and bacon, instead, provoked a “healthy” glucose response in his blood.
“That is the secret to optimizing your health,” he claims.
In a more recent video, Wittrock claims eating a red apple triggered “a shockingly bad” blood sugar reaction. “If you’re gonna eat an apple, Granny Smith is the way to go,” he says.
His videos are part of a trend of social media posts promoting the use of continuous glucose monitoring (CGM) devices — compact and now minimally invasive sensors that can be placed on one’s arm or abdomen to check glucose levels.
As of April 2023, the keyword “CGM” had gathered two billion views on TikTok.
French biochemist Jessie Inchauspe, who goes by “The Glucose Goddess” online, grew her Instagram following to more than 1.8 million by posting charts of her blood sugar levels after meals and sharing “hacks” to avoid “spikes” in a bestselling book titled “The Glucose Revolution.”
She has claimed on multiple platforms, including podcasts and television interviews, to teach “glucose science” helping people avoid glucose “events” by consuming vinegar before a meal or eating vegetables first.
But blood sugar usually increases after a meal, and medical professionals say this type of content can lead to potentially harmful habits.
Body reaction
A blood sugar level of less than 140 mg/dL is considered normal. While Wittrock labels levels above 140 as a “danger zone” in his content, exceeding that level for brief periods of time after a meal should not be cause for too much concern, experts told AFP.
“Everyone’s glucose will ‘spike’ after they eat, particularly a food that has a high glycemic index” like fruits or sugary beverages, said Dawn Davis, professor in the division of endocrinology, diabetes, and metabolism at the University of Wisconsin School of Medicine and Public Health.
“This is normal. In patients without diabetes, the body will secrete insulin to help clear this glucose load and the blood glucose will return to normal baseline levels within about 2 hours,” she said on April 3.
Christine Byrne, a registered dietitian in Raleigh, North Carolina, agreed. “There’s no reason to constantly be checking your blood sugar levels unless you have a medical condition like diabetes that necessitates it,” she told AFP on March 23.
A “laser focus” on glucose is not even recommended to diabetics as it can lead to people omitting healthy foods, said Rohin Francis, a British cardiologist and founder of a YouTube channel on science education. He said he has seen patients needlessly cut fruit or bread from their diets based on CGM readings.
“If a non-diabetic, healthy person eats a fruit, they will see their glucose rise slightly and then settle back to normal, whereas if they eat a burger, the glucose might change less,” he said on April 4. For diabetics, high glucose can be bad, but it is incorrect for a non-diabetic to “draw the conclusion that the fruit is more harmful to them than the burger,” he said.
The World Health Organization classifies cured meats and processed meats — including bacon that Wittrock qualifies as “healthy” in his glucose monitoring video — as carcinogens.
Francis said influencers like Inchauspe share “some sensible advice” — for example by highlighting the importance of dietary fiber for a healthy diet — but mix it with “factually incorrect statements.”
He pointed to her anecdote-driven “hacks” and questioned the evidence that reducing glucose spikes is preferable. The review cited by Inchauspe in this post about vinegar, for example, focuses on diabetic patients, he noted.
“For non-diabetic patients, my main concern is that we are pathologizing normal glucose physiology,” he said. “I have no problem with people recording data and being curious about how their bodies work, it’s what they’re doing with that data — and what influencers are telling them about that data — that has potential for harm.”
Risk of disordered eating
Abby Langer, a registered dietician in Toronto, Canada, said drawing comparisons between eating fudge with or without going for a run right after — like Inchauspe did in this post — could trigger restrictive dieting responses.
“Walking after meals is a great way to stabilize blood sugar. Running 5K after eating sweets is disordered. We don’t need to exercise to ‘burn off’ what we’ve eaten,” she told AFP on April 1.
The same is true for recommending a certain order in which to eat meals, Langer said.
“If we eat vegetables before starches, this may lessen glucose spikes, but to what end? In non-diabetics, this likely won’t make a difference. Also, feeling like we need to deconstruct meals to eat each food separately is disordered,” she warned.
Accessibility for diabetics
There is also a concern among medical professionals of potential shortages of glucose-monitoring devices for people who have diabetes, the University of Wisconsin’s Davis said.
“There are already a number of shortages/accessibility issues with many pharmaceuticals and supplies for patients with diabetes,” she said, citing the diabetes drug Ozempic as an example.
The injectable, prescription drug from Danish pharmaceutical firm Novo Nordisk was initially developed and approved in numerous nations to treat type 2 diabetes, and was shown to reduce appetite in patients, which led to a rise in popularity of Ozempic among people without diabetes.
“Even if this ‘off-label’ use does not actually cause the shortage, it means that when these things are in short supply for any reason our patients are competing with those who don’t truly need these medications or devices to improve their health,” she said.
AFP also reported on similar claims about glucose monitoring circulating in French, here.
