Personalized nutrition apps could provide valuable data to people trying to eat healthier, though more research must be done to show effectiveness.
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.”
Sonja Bauman, 39, and Mariela Florez, 83, taking one of their regular walks in Plantation, Fla. The pair met through an online platform called Papa that provides "family on demand." (Photo by Sonja Bauman)
In 2020, Papa connected Bauman, the 39-year-old Floridian, with another woman in her mid-70s who lives alone and has very limited mobility. Bauman began driving her to doctor’s appointments and helping her with chores around the house. “When I’m not there, she doesn’t leave her apartment,” said Bauman. The two have gone to the gym together, and they walk slowly through the neighborhood, chatting so it feels less like exercise.
Parker was driven to start Papa by the problem of social isolation among seniors, exacerbated by the pandemic, but he believes users of all ages can benefit. “Many of our Pals feel more comfortable opening up with older members than their same-aged friends,” he said.
Other platforms aim for similar, in-person connections. Generation Tech unites teens with seniors for technology training. And Mon Ami, which provides case management software for aging and disability service providers, has an app that connects isolated older people with college-age volunteers.
Making new connections through video
Several new sites match you with strangers for real-time video chatting on various topics, such as finding common ground on political issues. Other video platforms focus on intergenerational connections.
S. Jay Olshansky, a gerontology professor at the University of Illinois-Chicago, recalls the first time he saw Hyunseung Lee, an 11-year-old from Seoul, through his computer screen. The kid was shy, but Olshansky, 67, encouraged him to ask questions. “Turns out, he was thirsting for this kind of interaction.”
They’d connected through Eldera, a platform that pairs mentors age 60 and up with mentees, using an algorithm, for video conversations. “The time and wisdom of older adults is the most important natural resource we can give future generations,” said Dana Griffin, Eldera's CEO. “Connecting through a screen is the opposite of social media.”
In weekly meetings, Olshansky noticed Lee’s unique interest in math. “There’s something special in you,” Olshansky told him. “How do we bring it to the surface?” He suggested Lee write a book on his favorite subject, and the preteen ran with it, cranking out 70 pages in two weeks. Lee has published his love letter to theorems on Amazon.
Hyunseung Lee, age 11, of Korea, and U.S. college professor Jay Olshanksy, 67, discuss math, strategy and Hyunsung's budding career as a book author during their video chats through a platform called Eldera. (Photo by Dana Palmer/Eldera)
Lee’s parents told Olshansky that their son has become more assertive — a recurring theme, Griffin said. “Confidence is the number one thing parents tell us about.” Since Eldera’s inception last year, the number of mentors has grown exponentially. Even so, Griffin said the waitlist for mentors typically numbers 200 kids.
Another site, Big and Mini, hosts video interactions between seniors and young adults; about 10,000 active users have joined since 2019, said co-founder Aditi Merchant.
Users often bring the benefits of their video interactions to their real-world relationships. Olshansky views Lee as an older version of his grandkids. “Eldera teaches me how to interact with them.” Lee, high on confidence, began instructing his classmates in math. Griffin noted that a group of Eldera mentors in Memphis, who met initially on Eldera, now take walks together in-person to trade ideas for helping each other’s Eldera kids solve problems in their schools and communities.
“We’ve evolved into a community for older adults who want to give back to the world,” said Griffin. Other new tools for connection take the form of virtual reality apps.
Connecting in virtual reality
During pandemic isolation, record numbers of people bought devices for virtual and augmented reality. Such gadgets can convince you that you’re hanging out with friends, even if they’re in another hemisphere. Lifelike simulations from miles away could be especially useful for meaningful interactions between people of different generations, since they’re often geographically segregated.
VR’s benefits require further study, but users report less social isolation and depression, according to MIT research. The immersive, 3-D experience is more compelling than FaceTime or Zoom. “It’s like the difference between a phone call and video call,” said Rick Robinson, Vice President of AARP’s Innovation Labs.
“When VR is designed right, the medium disappears,” said Jeremy Bailenson of Stanford.
Dana Pierce, a 56-year-old government employee in Indiana, got Meta's VR headset in May, 2021, thinking she’d enjoy it more than a new laptop. After many virtual group tours of exotic destinations, she has no regrets. Her adventures occur on Alcove, an app made by Robinson’s Innovation Labs. He co-created it with VR-company Rendever and sought input from people over age 50 to tailor it to their interests. “I’m an introvert,” said Pierce. “I’ve been more socially active since getting my headset than I am in real life.”
Tagging along with her to places like Paris are avatars representing real people around the world. She’s gotten to know VR users in their 70s, 80s and 90s, as well as younger people and some her own age. One is a new friend she plays chess with in relaxing nature settings. Another is her oldest son. He lives 90 minutes away but, earlier this year, Pierce welcomed him and his girlfriend to her virtual house on Alcove. They chatted in the living room decorated with family photos uploaded by Pierce. Then they took out a boat to go VR fishing — because why not — until 2 a.m.
“When VR is designed right, the medium disappears,” said Jeremy Bailenson, a communications professor who directs Stanford’s Virtual Human Interaction Lab. He’s teaching a class of 175 students entirely in VR. After months of covid isolation, the first time the class met, “there was a big catharsis. It really feels like you’re in a big crowd.” Like-minded people meet in VR for events such as comedy shows and creative writing meetups, while the Swedish pop group ABBA has performed this year as digital versions of themselves (“ABBA-tars”) during a virtual concert tour.
Karen Fingerman, a psychologist and director of the Texas Aging and Longevity Center at the University of Texas-Austin, supports the idea of VR for social connection, though she added that some people need it more than others. Hospitals and assisted-living facilities are using products such as Penumbra’s REAL I-Series and MyndVR to bring VR excursions to isolated patients and seniors. “If you’re in a bed or facility, this gives you something to talk about,” said Gita Barry, Penumbra’s executive vice president.
Pierce uses it on most days. She may see another adult son, who lives with her, less often as a result. But VR helps her manage real-world stressors, more than escaping them. After a long workday, she visits her back porch on Alcove, which overlooks a pond. “It’s my little retreat,” she said. “VR improves my mood. It’s added a lot to my life.”
Some seniors are using more than one technology. Olshansky and Lee discuss strategy while playing Internet chess. And Olshansky recently began using VR. He sees his sister, who lives far away, in a virtual beach house. “It’d be a great way to interact with Hyunseung,” he said. “I should get him a headset.”
A version of this article first appeared in The Washington Post on December 3, 2021.