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.”
ECOTEK students Noah Harris, 8, and Amir Muhammad, 10, doing measurements for their wind turbine project.
When Keith Young was a young father shepherding his three children through the Detroit public school system, he felt something was missing.
The students are working on issues ranging from robotics to 3D printing to finding a cure for a rare form of cancer.
"What I'd observed was a gap between the resources that were being offered to university-level folks and in the professional ranks compared to what had been offered to kids in K-12, and in particular, the ones that were in urban and rural communities," he recalls. "There was always a Boys and Girls Camp, always a YMCA. There was never a YMCA for scientists."
Thus, the concept of ECOTEK Lab was born. Young's vision was to narrow that gap -- by financing pop-up labs for students who want to find a scientific solution to hard-to-solve problems that can be found in their own backyards.
He began in 2005, guiding his own children through foundational experiments for eventual startup companies, focusing on climate change, DNA, making biofuels and other fields of research. In addition to the labs, Young says ECOTEK has also reached young people by way of field trips, science fairs, and in-class demonstrations at schools. Young considers himself a venture capitalist, lending resources to kid and teen scientists.
Keith Young, foreground, is the founder of ECOTEK. Behind him, from left, are his daughter, Amber, son, Keith Jr., and ECOTEK students Emmanuel Jefferson and Antoine Crews.
(Courtesy Young)
In 2008, he took a group of six students from Detroit who had been researching brownfields, or previously developed land that's now vacant, and how they affect climate change; their work culminated in a research trip to Cape Town, South Africa, and participation in a conference there.
Today, he's helping transform the lives of around 250 student scientists across the country in places like Detroit, Florida and Maryland. Those students are working on issues ranging from robotics to 3D printing to finding a cure for a rare form of cancer.
Participating students do not receive a grade -- "they have to have passion to do the work." To take part, students must complete an application process and pay a small fee to use the lab, which is based on family resources, Young says. Students usually work in groups of two to three and are matched with a STEM mentor who can help when they run into research roadblocks.
In one lab in Detroit, a trio of teens is working to develop battery technology for smart mobility along with microbial fuel cells. In another lab, students focus on plant-based drug discovery. One of their projects is using plant DNA to better understand how the breast cancer gene mutation called BRCA1 works in the human body. In the African American population, about 35 percent of women with triple-negative breast cancer test positive for this mutation, and they usually don't learn of their diagnosis until the cancer has spread.
ECOTEK students have also had a slightly larger audience – the United Nations.
A third Detroit-based lab is led by Keith Young's daughter and one of ECOTEK's original students: Founder Briana Young, 23, runs a spin-off business called SmartFarms, which works on food security and developing food safety systems for urban farming using advanced drone technology and biochemical sensory systems. According to a recent report, more than 30,000 Detroiters don't have access to a full-service grocery store, and 48 percent are considered food insecure.
"We don't tell them which subjects to do – that's why [the labs] are not working on the same thing," explains Young. "We're trying to give student scientists a place to find their way."
The gap that Young noticed for urban students exists also among rural communities, and the problems they face are different. Students in a lab in Polk County, Florida, decided to tackle citrus greening, a bacterial disease that causes citrus fruit to bear bitter-tasting and underdeveloped fruit. The culprit is the Asian psyllid, a pest common to citrus plants. The problem is so pervasive that it's caused a precipitous decline in the industry, which had been a major one in Polk. At Bok Academy in Lake Wales, also in Florida, students are using drones to get an overhead view of the patterns they can detect to better understand which trees to treat and when.
"With the majority of our area dependent on citrus and various other crops, why not get students involved in problem-solving and research that's going to truly make a difference?" says David Lockett, a STEM facilitator at Bok Academy.
To this end, the students have shared their findings with scientists at the University of Florida and a research lab in Colorado.
A young woman who started in ECOTEK as an elementary-school student will now, at age 24, return to run the research arm of the company.
ECOTEK students have also had a slightly larger audience – the United Nations. The Detroit students have traveled to New York since 2013 to share their learnings with international diplomats from countries like Belize, Cuba, and Antigua.
The students' hands-on experience in the lab often inspires them to pursue academic success across the board at school. Young says that graduating students usually receive an average of $150,000 in college scholarships and score an average of 1450 on the SATs and in the 90th percentile on ACT tests.
Young plans to continue his work to develop these scientists, and after having invested "millions" of dollars of his own money, he's now seeing the fruits of his labor come full circle. A young woman who started in ECOTEK as an elementary-school student will now, at age 24, return to run the research arm of the company.
"It was," he says proudly, "a 14-year investment payback."
Cows on a pasture, who, among other mammals, could experience immense suffering from the New World screwworm.
Combining CRISPR genome editing with the natural phenomenon of gene drive allows us to rewrite the genomes of wild organisms. The benefits of saving children from malaria by editing mosquitoes are obvious and much discussed, but humans aren't the only creatures who suffer. If we gain the power to intervene in a natural world "red in tooth and claw," yet decline to use it, are we morally responsible for the animal suffering that we could have prevented?
Given the power to alter the workings of the natural world, are we morally obligated to use it?
The scenario that may redefine our relationship with the natural world begins with fine clothing. You're dressed to the nines for a formal event, but you arrived early, and it's such a beautiful day that you decided to take a stroll by the nearby lake. Suddenly, you hear the sound of splashing and screams. A child is drowning! Will you dive in to save them? Or let them die, and preserve your expensive outfit?
The philosopher Peter Singer posited this scenario to show that we are all terrible human beings. Just about everyone would save the child and ruin the outfit... leading Singer to question why so few of us give equivalent amounts of money to save children on the other side of the world. The Against Malaria Foundation averages one life saved for every $7000.
But despite having a local bias, our moral compasses aren't completely broken. You never even considered letting the child drown because the situation wasn't your fault. That's because the cause of the problem simply isn't relevant: as the one who could intervene, the consequences are on your head. We are morally responsible for intervening in situations we did not create.
There is a critical difference between Singer's original scenario and the one above: in his version, it was a muddy pond. Any adult can rescue a child from a muddy pond, but a lake is different; you can only save the child if you know how to swim. We only become morally responsible when we acquire the power to intervene.
Few would disagree with either of these moral statements, but when they are combined with increasingly powerful technologies, the implications are deeply unsettling. Given the power to alter the workings of the natural world, are we morally obligated to use it? Recent developments suggest we had best determine the answer soon because, technologically, we are learning to swim. What choices will we make?
Gene drive is a natural phenomenon that occurs when a genetic element reliably spreads through a population even though it reduces the reproductive fitness of individual organisms. Nature has evolved many different mechanisms that result in gene drive, so many that it's nearly impossible to find an organism that doesn't have at least one driving element somewhere in its genome. More than half of our own DNA comprises the broken remnants of gene drives, plus a few active copies.
Scientists have long dreamed of harnessing gene drive to block mosquito-borne disease, with little success. Then came CRISPR genome editing, which works by cutting target genes and replacing them with a new sequence. What happens if you replace the original sequence with the edited version and an encoded copy of the CRISPR system? Gene drive.
CRISPR is a molecular scalpel that we can use to cut, and therefore replace, just about any DNA sequence in any cell. Encode the instructions for the CRISPR system adjacent to the new sequence, and genome editing will occur in the reproductive cells of subsequent generations of heterozygotes, always converting the original wild-type version to the new edited version. By ensuring that offspring will all be born of one sex, or by arranging for organisms that inherit two copies of the gene drive to be sterile, it's theoretically possible to cause a population crash.
(Credit: Esvelt)
When my colleagues and I first described this technology in 2014, we initially focused on the imperative for early transparency. Gene drive research is more like civic governance than traditional technology development: you can decline a treatment recommended by your doctor, but you can’t opt out when people change the shared environment. Applying the traditional closeted model of science to gene drive actively denies people a voice in decisions intended to affect them - and reforming scientific incentives for gene drive could be the first step to making all of science faster and safer.
But open gene drive research is clearly aligned with virtually all of our values. It's when technology places our deepest moral beliefs in conflict that we struggle, and learn who we truly are.
Two of our strongest moral beliefs include our reverence for the natural world and our abhorrence of suffering. Yet some natural species inherently cause tremendous suffering. Are we morally obligated to alter or even eradicate them?
To anyone who doubts that the natural world can inflict unimaginable suffering, consider the New World screwworm.
Judging by history, the answer depends on who is doing the suffering. We view the eradication of smallpox as one of our greatest triumphs, clearly demonstrating that we value human lives over the existence of disease-causing microorganisms. The same principle holds today for malaria: few would argue against using gene drive to crash populations of malarial mosquitoes to help eradicate the disease. There are more than 3500 species of mosquitoes, only three of which would be affected, and once malaria is gone, the mosquitoes could be allowed to recover. It would be extremely surprising if African nations decided not to eradicate malaria.
The more interesting question concerns our moral obligations to animals in the state of nature.
To anyone who doubts that the natural world can inflict unimaginable suffering, consider the New World screwworm, Cochyliomyia hominivorax. Female screwworm flies lay their eggs in open wounds, generating maggots that devour healthy tissue, gluttonously burrowing into the flesh of their host until they drop, engorged and sated, to metamorphose. Yet before they fall, the maggots in a wound emit a pheromone attracting new females, thereby acting as both conductors and performers in a macabre parade that consumes the host alive. The pain is utterly excruciating, so much so that infested people often require morphine before doctors can even examine the wound. Worst of all, the New World screwworm specializes in devouring complex mammals.
Every second of every day, hundreds of millions of animals suffer the excruciating agony of being eaten alive. It has been so throughout North and South America for millions of years. Until 2001, when humanity eradicated the last screwworm fly north of Panama using the “sterile insect techniqueâ€. This was not done to protect wild animals or even people, but for economic reasons: the cost of the program was small relative to the immense damage wrought by the screwworm on North American cattle, sheep, and goats. There were no obvious ecological effects. Despite being almost completely unknown even among animal rights activists, the screwworm elimination campaign may well have been one of the greatest triumphs of animal well-being.
Unfortunately, sterile insect technique isn't powerful enough to eradicate the screwworm from South America, where it is more entrenched and protected by the rougher terrain. But gene drive is.
Contrary to news hype, gene drive alone can't cause extinction, but if combined with conventional measures it might be possible to remove targeted species from the wild. For certain species that cause immense suffering, we may be morally obligated to do just that.
(Credit: Esvelt)
South Americans may well decide to eradicate screwworm for the same economic reasons that it was eradicated from North America: the fly inflicts $4 billion in annual damages on struggling rural communities that can least afford it. It need not go extinct, of course; the existence of the sterile insect facility in Panama proves that we can maintain the screwworm indefinitely in captivity on already dead meat.
Yet if for some reason humanity chooses to leave the screwworm as it is - even for upstanding moral reasons, whatever those may be - the knowledge of our responsibility should haunt us.
Tennyson wrote,
Are God and Nature then at strife,
That Nature lends such evil dreams?
So careful of the type she seems,
So careless of the single life.
Evolution by natural selection cares nothing for the single life, nor suffering, nor euphoria, save for their utility in replication. Theoretically, we do. But how much?
[Editor's Note: This story was originally published in May 2018. We are resurfacing archive hits while our staff is on vacation.]