AI and you: Is the promise of personalized nutrition apps worth the hype?
As a type 2 diabetic, Michael Snyder has long been interested in how blood sugar levels vary from one person to another in response to the same food, and whether a more personalized approach to nutrition could help tackle the rapidly cascading levels of diabetes and obesity in much of the western world.
Eight years ago, Snyder, who directs the Center for Genomics and Personalized Medicine at Stanford University, decided to put his theories to the test. In the 2000s continuous glucose monitoring, or CGM, had begun to revolutionize the lives of diabetics, both type 1 and type 2. Using spherical sensors which sit on the upper arm or abdomen – with tiny wires that pierce the skin – the technology allowed patients to gain real-time updates on their blood sugar levels, transmitted directly to their phone.
It gave Snyder an idea for his research at Stanford. Applying the same technology to a group of apparently healthy people, and looking for ‘spikes’ or sudden surges in blood sugar known as hyperglycemia, could provide a means of observing how their bodies reacted to an array of foods.
“We discovered that different foods spike people differently,” he says. “Some people spike to pasta, others to bread, others to bananas, and so on. It’s very personalized and our feeling was that building programs around these devices could be extremely powerful for better managing people’s glucose.”
Unbeknown to Snyder at the time, thousands of miles away, a group of Israeli scientists at the Weizmann Institute of Science were doing exactly the same experiments. In 2015, they published a landmark paper which used CGM to track the blood sugar levels of 800 people over several days, showing that the biological response to identical foods can vary wildly. Like Snyder, they theorized that giving people a greater understanding of their own glucose responses, so they spend more time in the normal range, may reduce the prevalence of type 2 diabetes.
The commercial potential of such apps is clear, but the underlying science continues to generate intriguing findings.
“At the moment 33 percent of the U.S. population is pre-diabetic, and 70 percent of those pre-diabetics will become diabetic,” says Snyder. “Those numbers are going up, so it’s pretty clear we need to do something about it.”
Fast forward to 2022,and both teams have converted their ideas into subscription-based dietary apps which use artificial intelligence to offer data-informed nutritional and lifestyle recommendations. Snyder’s spinoff, January AI, combines CGM information with heart rate, sleep, and activity data to advise on foods to avoid and the best times to exercise. DayTwo–a start-up which utilizes the findings of Weizmann Institute of Science–obtains microbiome information by sequencing stool samples, and combines this with blood glucose data to rate ‘good’ and ‘bad’ foods for a particular person.
“CGMs can be used to devise personalized diets,” says Eran Elinav, an immunology professor and microbiota researcher at the Weizmann Institute of Science in addition to serving as a scientific consultant for DayTwo. “However, this process can be cumbersome. Therefore, in our lab we created an algorithm, based on data acquired from a big cohort of people, which can accurately predict post-meal glucose responses on a personal basis.”
The commercial potential of such apps is clear. DayTwo, who market their product to corporate employers and health insurers rather than individual consumers, recently raised $37 million in funding. But the underlying science continues to generate intriguing findings.
Last year, Elinav and colleagues published a study on 225 individuals with pre-diabetes which found that they achieved better blood sugar control when they followed a personalized diet based on DayTwo’s recommendations, compared to a Mediterranean diet. The journal Cell just released a new paper from Snyder’s group which shows that different types of fibre benefit people in different ways.
“The idea is you hear different fibres are good for you,” says Snyder. “But if you look at fibres they’re all over the map—it’s like saying all animals are the same. The responses are very individual. For a lot of people [a type of fibre called] arabinoxylan clearly reduced cholesterol while the fibre inulin had no effect. But in some people, it was the complete opposite.”
Eight years ago, Stanford's Michael Snyder began studying how continuous glucose monitors could be used by patients to gain real-time updates on their blood sugar levels, transmitted directly to their phone.
The Snyder Lab, Stanford Medicine
Because of studies like these, interest in precision nutrition approaches has exploded in recent years. In January, the National Institutes of Health announced that they are spending $170 million on a five year, multi-center initiative which aims to develop algorithms based on a whole range of data sources from blood sugar to sleep, exercise, stress, microbiome and even genomic information which can help predict which diets are most suitable for a particular individual.
“There's so many different factors which influence what you put into your mouth but also what happens to different types of nutrients and how that ultimately affects your health, which means you can’t have a one-size-fits-all set of nutritional guidelines for everyone,” says Bruce Y. Lee, professor of health policy and management at the City University of New York Graduate School of Public Health.
With the falling costs of genomic sequencing, other precision nutrition clinical trials are choosing to look at whether our genomes alone can yield key information about what our diets should look like, an emerging field of research known as nutrigenomics.
The ASPIRE-DNA clinical trial at Imperial College London is aiming to see whether particular genetic variants can be used to classify individuals into two groups, those who are more glucose sensitive to fat and those who are more sensitive to carbohydrates. By following a tailored diet based on these sensitivities, the trial aims to see whether it can prevent people with pre-diabetes from developing the disease.
But while much hope is riding on these trials, even precision nutrition advocates caution that the field remains in the very earliest of stages. Lars-Oliver Klotz, professor of nutrigenomics at Friedrich-Schiller-University in Jena, Germany, says that while the overall goal is to identify means of avoiding nutrition-related diseases, genomic data alone is unlikely to be sufficient to prevent obesity and type 2 diabetes.
“Genome data is rather simple to acquire these days as sequencing techniques have dramatically advanced in recent years,” he says. “However, the predictive value of just genome sequencing is too low in the case of obesity and prediabetes.”
Others say that while genomic data can yield useful information in terms of how different people metabolize different types of fat and specific nutrients such as B vitamins, there is a need for more research before it can be utilized in an algorithm for making dietary recommendations.
“I think it’s a little early,” says Eileen Gibney, a professor at University College Dublin. “We’ve identified a limited number of gene-nutrient interactions so far, but we need more randomized control trials of people with different genetic profiles on the same diet, to see whether they respond differently, and if that can be explained by their genetic differences.”
Some start-ups have already come unstuck for promising too much, or pushing recommendations which are not based on scientifically rigorous trials. The world of precision nutrition apps was dubbed a ‘Wild West’ by some commentators after the founders of uBiome – a start-up which offered nutritional recommendations based on information obtained from sequencing stool samples –were charged with fraud last year. The weight-loss app Noom, which was valued at $3.7 billion in May 2021, has been criticized on Twitter by a number of users who claimed that its recommendations have led to them developed eating disorders.
With precision nutrition apps marketing their technology at healthy individuals, question marks have also been raised about the value which can be gained through non-diabetics monitoring their blood sugar through CGM. While some small studies have found that wearing a CGM can make overweight or obese individuals more motivated to exercise, there is still a lack of conclusive evidence showing that this translates to improved health.
However, independent researchers remain intrigued by the technology, and say that the wealth of data generated through such apps could be used to help further stratify the different types of people who become at risk of developing type 2 diabetes.
“CGM not only enables a longer sampling time for capturing glucose levels, but will also capture lifestyle factors,” says Robert Wagner, a diabetes researcher at University Hospital Düsseldorf. “It is probable that it can be used to identify many clusters of prediabetic metabolism and predict the risk of diabetes and its complications, but maybe also specific cardiometabolic risk constellations. However, we still don’t know which forms of diabetes can be prevented by such approaches and how feasible and long-lasting such self-feedback dietary modifications are.”
Snyder himself has now been wearing a CGM for eight years, and he credits the insights it provides with helping him to manage his own diabetes. “My CGM still gives me novel insights into what foods and behaviors affect my glucose levels,” he says.
He is now looking to run clinical trials with his group at Stanford to see whether following a precision nutrition approach based on CGM and microbiome data, combined with other health information, can be used to reverse signs of pre-diabetes. If it proves successful, January AI may look to incorporate microbiome data in future.
“Ultimately, what I want to do is be able take people’s poop samples, maybe a blood draw, and say, ‘Alright, based on these parameters, this is what I think is going to spike you,’ and then have a CGM to test that out,” he says. “Getting very predictive about this, so right from the get go, you can have people better manage their health and then use the glucose monitor to help follow that.”
Meet the Shoe That Will Never End Up in a Landfill
Have you ever wondered what happens to your worn-out sneakers when you throw them away? They will likely spend the next few decades decomposing in a landfill.
"You simply take it, grind it up and make a new one. But under the surface, it's extremely technical and complex."
According to the most current government statistics, eight million tons of shoes and clothing were sent to landfills in 2015 alone. As the trashed items break down over many years, they produce toxic greenhouse gases like methane and carbon dioxide, contributing to global climate change.
The Lowdown
Sportswear manufacturer adidas was well aware of their industry's harmful environmental impact, so they set out to become part of the solution. A few years ago, they partnered with various companies to gather and reuse plastics from the ocean to make clothes and parts of shoes.
Then they wondered if they could take their vision a step further: Could they end the concept of waste entirely?
This ambition drove them to create a high-performance athletic shoe made with entirely reusable material – the new FutureCraft Loop. It's a shoe you never have to throw out.
"It's something that outwardly appears very simple," said Paul Gaudio, adidas' Global Creative Director. "You simply take it, grind it up and make a new one. I think that's super elegant and easy to understand. But under the surface, it's extremely technical and complex and it is quite literally a science project."
This project began with a group of engineers, material scientists, and designers trying to find a material that could be pliable enough to take the place of 10-12 different components normally used to make a shoe, yet durable enough to provide the support a running shoe requires. The team decided on thermoplastic polyurethane (TPU), a strong and versatile material that can be re-melted and re-molded even after it's solidified. The team worked for close to a decade on research and development.
Adidas FUTURECRAFT.LOOP
The result, Gaudio said, is an athletic shoe that doesn't compromise on quality and also won't pollute the planet. The wearer will likely notice the shoe feels different because it's welded together by heat alone.
"You feel a more direct connection [to the shoe] because you don't have the layers and glue," he explained.
Next Up
One of the next steps will be for adidas to engage with consumers to find out the best way to get them to return their used shoes for recycling so that they can, so to say, close the loop.
"We're trying to decide what that looks like," Gaudio said. "Is it a take-back program, is it a subscription mode? Do you return it at stores? So that's the next big challenge that we're working on and that's why we've started to engage people outside the brand in that process."
The FutureCraft Loop is in beta testing with a small group, but if all goes well, the shoe may be available for purchase in early 2021. The pricing hasn't been set, but Gaudio said that the goal is to make it affordable.
"If it's something that's too exclusive or unattainable," he said, "it defeats the purpose."
Open Questions
Although TPU is a completely recyclable material, the team at adidas is working to perfect the process.
"We have a passion to apply creativity and imagination to the problems of plastic in the oceans and the plastic waste."
"Each time you recycle something there is a change – a degradation and contamination," Gaudio noted. "So if I ground the whole thing up, can I make the exact same shoe again with this exact same batch of material today? No, but we can still recycle 100 percent of it. But we're working towards being able to take the knit upper and make a new knit upper."
Gaudio hopes that other companies will follow suit, although adidas is moving to develop ownership of their solutions, including the process behind making the FutureCraft Loop.
"We have a passion to apply creativity and imagination to the problems of plastic in the oceans and the plastic waste and that's what's driving us," he said.
Kelly Mantoan was nursing her newborn son, Teddy, in the NICU in a Philadelphia hospital when her doctor came in and silently laid a hand on her shoulder. Immediately, Kelly knew what the gesture meant and started to sob: Teddy, like his one-year-old brother, Fulton, had just tested positive for a neuromuscular condition called spinal muscular atrophy (SMA).
The boys were 8 and 10 when Kelly heard about an experimental new treatment, still being tested in clinical trials, called Spinraza.
"We knew that [SMA] was a genetic disorder, and we knew that we had a 1 in 4 chance of Teddy having SMA," Mantoan recalls. But the idea of having two children with the same severe disability seemed too unfair for Kelly and her husband, Tony, to imagine. "We had lots of well-meaning friends tell us, well, God won't do this to you twice," she says. Except that He, or a cruel trick of nature, had.
In part, the boys' diagnoses were so devastating because there was little that could be done at the time, back in 2009 and 2010, when the boys were diagnosed. Affecting an estimated 1 in 11,000 babies, SMA is a degenerative disease in which the body is deficient in survival motor neuron (SMN) protein, thanks to a genetic mutation or absence of the body's SNM1 gene. So muscles that control voluntary movement – such as walking, breathing, and swallowing – weaken and eventually cease to function altogether.
Babies diagnosed with SMA Type 1 rarely live past toddlerhood, while people diagnosed with SMA Types 2, 3, and 4 can live into adulthood, usually with assistance like ventilators and feeding tubes. Shortly after birth, both Teddy Mantoan and his brother, Fulton, were diagnosed with SMA Type 2.
The boys were 8 and 10 when Kelly heard about an experimental new treatment, still being tested in clinical trials, called Spinraza. Up until then, physical therapy was the only sanctioned treatment for SMA, and Kelly enrolled both her boys in weekly sessions to preserve some of their muscle strength as the disease marched forward. But Spinraza – a grueling regimen of lumbar punctures and injections designed to stimulate a backup survival motor neuron gene to produce more SMN protein – offered new hope.
In clinical trials, after just a few doses of Spinraza, babies with SMA Type 1 began meeting normal developmental milestones – holding up their heads, rolling over, and sitting up. In other trials, Spinraza treatment delayed the need for permanent ventilation, while patients on the placebo arm continued to lose function, and several died. Spinraza was such a success, and so well tolerated among patients, that clinical trials ended early and the drug was fast-tracked for FDA approval in 2016. In January 2017, when Kelly got the call that Fulton and Teddy had been approved by the hospital to start Spinraza infusions, Kelly dropped to her knees in the middle of the kitchen and screamed.
Spinraza, manufactured by Biogen, has been hailed as revolutionary, but it's also not without drawbacks: Priced per injection, just one dose of Spinraza costs $125,000, making it one of the most expensive drugs on the global market. What's worse, treatment requires a "loading dose" of four injections over a four-week period, and then periodic injections every four months, indefinitely. For the first year of treatment, Spinraza treatment costs $750,000 – and then $375,000 for every year thereafter.
Last week, a competitive treatment for SMA Type 1 manufactured by Novartis burst onto the market. The new treatment, called Zolgensma, is a one-time gene therapy intended to be given to infants and is currently priced at $2.125 million, or $425,000 annually for five years, making it the most expensive drug in the world. Like Spinraza, Zolgensma is currently raising challenging questions about how insurers and government payers like Medicaid will be able to afford these treatments without bankrupting an already-strained health care system.
To Biogen's credit, the company provides financial aid for Spinraza patients with private insurance who pay co-pays for treatment, as well as for those who have been denied by Medicaid and Medicare. But getting insurance companies to agree to pay for Spinraza can often be an ordeal in itself. Although Fulton and Teddy Mantoan were approved for treatment over two years ago, a lengthy insurance battle delayed treatment for another eight months – time that, for some SMA patients, can mean a significant loss of muscular function.
Kelly didn't notice anything in either boy – positive or negative – for the first few months of Spinraza injections. But one day in November 2017, as Teddy was lowered off his school bus in his wheelchair, he turned to say goodbye to his friends and "dab," – a dance move where one's arms are extended briefly across the chest and in the air. Normally, Teddy would dab by throwing his arms up in the air with momentum, striking a pose quickly before they fell down limp at his sides. But that day, Teddy held his arms rigid in the air. His classmates, along with Kelly, were stunned. "Teddy, look at your arms!" Kelly remembers shrieking. "You're holding them up – you're dabbing!"
Teddy and Fulton Mantoan, who both suffer from spinal muscular atrophy, have seen life-changing results from Spinraza.
(Courtesy of Kelly Mantoan)
Not long after Teddy's dab, the Mantoans started seeing changes in Fulton as well. "With Fulton, we realized suddenly that he was no longer choking on his food during meals," Kelly said. "Almost every meal we'd have to stop and have him take a sip of water and make him slow down and take small bites so he wouldn't choke. But then we realized we hadn't had to do that in a long time. The nurses at school were like, 'it's not an issue anymore.'"
For the Mantoans, this was an enormous relief: Less choking meant less chance of aspiration pneumonia, a leading cause of death for people with SMA Types 1 and 2.
While Spinraza has been life-changing for the Mantoans, it remains painfully out of reach for many others. Thanks to Spinraza's enormous price tag, the threshold for who gets to use it is incredibly high: Adult and pediatric patients, particularly those with state-sponsored insurance, have reported multiple insurance denials, lengthy appeals processes, and endless bureaucracy from insurance and hospitals alike that stand in the way of treatment.
Kate Saldana, a 21-year-old woman with Type 2 SMA, is one of the many adult patients who have been lobbying for the drug. Saldana, who uses a ventilator 20 hours each day, says that Medicaid denied her Spinraza treatments because they mistakenly believed that she used a ventilator full-time. Saldana is currently in the process of appealing their decision, but knows she is fighting an uphill battle.
Kate Saldana, who suffers from Type 2 SMA, has been fighting unsuccessfully for Medicaid to cover Spinraza.
(Courtesy of Saldana)
"Originally, the treatments were studied and created for infants and children," Saldana said in an e-mail. "There is a plethora of data to support the effectiveness of Spinraza in those groups, but in adults it has not been studied as much. That makes it more difficult for insurance to approve it, because they are not sure if it will be as beneficial."
Saldana has been pursuing treatment unsuccessfully since last August – but others, like Kimberly Hill, a 32-year-old with SMA Type 2, have been waiting even longer. Hill, who lives in Oklahoma, has been fighting for treatment since Spinraza went on the U.S. market in December 2016. Because her mobility is limited to the use of her left thumb, Hill is eager to try anything that will enable her to keep working and finish a Master's degree in Fire and Emergency Management.
"Obviously, my family and I were elated with the approval of Spinraza," Hill said in an e-mail. "We thought I would finally have the chance to get a little stronger and healthier." But with Medicare and Medicaid, coverage and eligibility varies wildly by state. Earlier this year, Medicaid approved Spinraza for adult patients only if a clawback clause was attached to the approval, meaning that under certain conditions the Medicaid funds would need to be paid back. Because of the clawback clause, hospitals have been reluctant to take on Spinraza treatments, effectively barring adult Medicaid patients from accessing the drug altogether.
Hill's hospital is currently in negotiations with Medicaid to move forward with Spinraza treatment, but in the meantime, Hill is in limbo. "We keep being told there is nothing we can do, and we are devastated," Hill said.
"I felt extremely sad and honestly a bit forgotten, like adults [with SMA] don't matter."
Between Spinraza and its new competitor, Zolgensma, some are speculating that insurers will start to favor Zolgensma coverage instead, since the treatment is shorter and ultimately cheaper than Spinraza in the long term. But for some adults with SMA who can't access Spinraza and who don't qualify for Zolgensma treatment, the issue of what insurers will cover is moot.
"I was so excited when I heard that Zolgensma was approved by the FDA," said Annie Wilson, an adult SMA patient from Alameda, Calif. who has been fighting for Spinraza since 2017. "When I became aware that it was only being offered to children, I felt extremely sad and honestly a bit forgotten, like adults [with SMA] don't matter."
According to information from a Biogen representative, more than 7500 people worldwide have been treated with Spinraza to date, one third of whom are adults.
While Spinraza has been revolutionary for thousands of patients, it's unclear how many more lives state agencies and insurance companies will allow it to save.