Transistors, the building blocks of modern electronics, are typically made of silicon. Because it’s a semiconductor, this material can control the flow of electricity in a circuit. But silicon has fundamental physical limits that restrict how compact and energy-efficient a transistor can be.

MIT researchers have now replaced silicon with a magnetic semiconductor, creating a magnetic transistor that could enable smaller, faster, and more energy-efficient circuits. The material’s magnetism strongly influences its electronic behavior, leading to more efficient control of the flow of electricity. 

The team used a novel magnetic material and an optimization process that reduces the material’s defects, which boosts the transistor’s performance.

The material’s unique magnetic properties also allow for transistors with built-in memory, which would simplify circuit design and unlock new applications for high-performance electronics.

“People have known about magnets for thousands of years, but there are very limited ways to incorporate magnetism into electronics. We have shown a new way to efficiently utilize magnetism that opens up a lot of possibilities for future applications and research,” says Chung-Tao Chou, an MIT graduate student in the departments of Electrical Engineering and Computer Science (EECS) and Physics, and co-lead author of a paper on this advance.

Chou is joined on the paper by co-lead author Eugene Park, a graduate student in the Department of Materials Science and Engineering (DMSE); Julian Klein, a DMSE research scientist; Josep Ingla-Aynes, a postdoc in the MIT Plasma Science and Fusion Center; Jagadeesh S. Moodera, a senior research scientist in the Department of Physics; and senior authors Frances Ross, TDK Professor in DMSE; and Luqiao Liu, an associate professor in EECS, and a member of the Research Laboratory of Electronics; as well as others at the University of Chemistry and Technology in Prague. The paper appears today in Physical Review Letters.

Overcoming the limits

In an electronic device, silicon semiconductor transistors act like tiny light switches that turn a circuit on and off, or amplify weak signals in a communication system. They do this using a small input voltage.

But a fundamental physical limit of silicon semiconductors prevents a transistor from operating below a certain voltage, which hinders its energy efficiency.

To make more efficient electronics, researchers have spent decades working toward magnetic transistors that utilize electron spin to control the flow of electricity. Electron spin is a fundamental property that enables electrons to behave like tiny magnets.

So far, scientists have mostly been limited to using certain magnetic materials. These lack the favorable electronic properties of semiconductors, constraining device performance.

“In this work, we combine magnetism and semiconductor physics to realize useful spintronic devices,” Liu says.

The researchers replace the silicon in the surface layer of a transistor with chromium sulfur bromide, a two-dimensional material that acts as a magnetic semiconductor.

Due to the material’s structure, researchers can switch between two magnetic states very cleanly. This makes it ideal for use in a transistor that smoothly switches between “on” and “off.”

“One of the biggest challenges we faced was finding the right material. We tried many other materials that didn’t work,” Chou says.

They discovered that changing these magnetic states modifies the material’s electronic properties, enabling low-energy operation. And unlike many other 2D materials, chromium sulfur bromide remains stable in air.

To make a transistor, the researchers pattern electrodes onto a silicon substrate, then carefully align and transfer the 2D material on top. They use tape to pick up a tiny piece of material, only a few tens of nanometers thick, and place it onto the substrate.

“A lot of researchers will use solvents or glue to do the transfer, but transistors require a very clean surface. We eliminate all those risks by simplifying this step,” Chou says.

Leveraging magnetism

This lack of contamination enables their device to outperform existing magnetic transistors. Most others can only create a weak magnetic effect, changing the flow of current by a few percent or less. Their new transistor can switch or amplify the electric current by a factor of 10.

They use an external magnetic field to change the magnetic state of the material, switching the transistor using significantly less energy than would usually be required.

The material also allows them to control the magnetic states with electric current. This is important because engineers cannot apply magnetic fields to individual transistors in an electronic device. They need to control each one electrically.

The material’s magnetic properties could also enable transistors with built-in memory, simplifying the design of logic or memory circuits.

A typical memory device has a magnetic cell to store information and a transistor to read it out. Their method can combine both into one magnetic transistor.

“Now, not only are transistors turning on and off, they are also remembering information. And because we can switch the transistor with greater magnitude, the signal is much stronger so we can read out the information faster, and in a much more reliable way,” Liu says.

Building on this demonstration, the researchers plan to further study the use of electrical current to control the device. They are also working to make their method scalable so they can fabricate arrays of transistors.

This research was supported, in part, by the Semiconductor Research Corporation, the U.S. Defense Advanced Research Projects Agency (DARPA), the U.S. National Science Foundation (NSF), the U.S. Department of Energy, the U.S. Army Research Office, and the Czech Ministry of Education, Youth, and Sports. The work was partially carried out at the MIT.nano facilities.

The California legislature has stepped back from a plan that would have expanded its age-gating law, removing language that could have compounded serious threats to users’ speech, privacy and security just to browse the internet. A.B. 1856, authored by Assemblymember Buffy Wicks, will now move forward through the legislature without its most problematic pieces.

EFF still believes the underlying law that A.B. 1856 amends, A.B. 1043, is unconstitutional. Signed into law in 2025 (and effective January of 2027), A.B. 1043 requires all operating systems and app stores to collect users’ ages, place them in various age brackets and then block young people from lawful speech and services depending on their age. We also believe that even though A.B. 1043 does not require age verification, the liability it creates for operating systems and app stores—including fining operating systems up to $7,500 per affected child for violating the law—will push those services to verify users’ ages. In practice, that could lead to more ID checks, more biometric scanning, more invasive data collection and risk of breach, and more barriers to adults’ and young people’s lawful speech.

However, we appreciate that the Legislature has abandoned its plan to expand this problematic age-gating  framework to browsers and websites. This would have significantly expanded this dangerous law before it even took effect. We thank the author and committee staff for recognizing these harms and not moving forward with this language. 

On top of that, EFF is pleased that an earlier amendment to A.B 1856 reduced the threat to the open-source community by exempting open-source operating systems. Given these changes, EFF has removed its opposition to A.B. 1856. We appreciate the author for listening to concerns from advocates, developers and others about the effect it would have on open-source development and also around expanding this problematic framework.

To be clear, we still believe the law passed last year threatens online anonymity, privacy, and security. A.B. 1043 is one of a troubling wave of proposals that encourage—or, in some cases, outright require—age verification. Our position on this is clear: no one should have to provide or verify their age to access the internet. Once users’ personal data is collected, it can easily be leaked, hacked, or misused. No matter the method, every age verification system demands that people hand over their sensitive and immutable personal information to link their offline identity to their online activity. That’s a bad deal for us all.

Age-gating mandates are reshaping the internet in ways that are invasive, dangerous, and deeply unnecessary. But users are not powerless! We can challenge these laws, protect our digital rights, and build a safer digital world for all internet users, no matter their ages. This resource hub can help—so explore, share, and join us in the fight for a better internet.

Oura Rings, Garmin GPS fitness watches, Apple Watches, Whoop bands—every year, more and more tech devices are promising to monitor our health and fitness, guide us toward healthier living, and provide useful health metrics to take to our doctors. But few of these tools provide the sorts of privacy and security promises we demand from all technology, let alone tech that captures personal health data. It’s time they step up and start providing transparency reports and stronger encryption options.

Surveys suggest that around 40 percent of people in the United States own some sort of commercially available wearable health device. Despite being marketed as health devices, they have no special health-related privacy protections that one might hope for. The companies who make these devices can and do collect an abundance of data, and many of them share that data with third-parties for marketing or to influence insurance rates, or use it for their own purposes, like training artificial intelligence models.

Health data is increasingly an important part of law enforcement or government investigations. Wearable data has been critical in a number of cases, where information about heart rate and steps was used to determine the whereabouts of individuals. And the surveillance company Penlink calls fitness trackers and wearables an “overlooked source” for law enforcement since they tend to show movement patterns and changes in heart rates. Law enforcement can try to get access to this data through subpoenas or warrants. 

There are many potential privacy issues with these sorts of devices, including whether the companies who make them share or sell information to third-parties. But here we are choosing to focus on two facets we’re concerned with around health data itself: 1) whether the company shares information with law enforcement and governments and 2) if they offer end-to-end encryption, which means the company itself can’t access that health data to begin with.

Reading through dozens of product review sites we narrowed our research in on ten companies that seem to make the majority of recommended consumer health products on the market:

• Amazfit
• Apple
• Coros
• Garmin
• Google (including Fitbit)
• Hume
• Oura
• Polar
• Suunto
• Whoop 

We reviewed each company’s public facing policies, then emailed them to confirm those findings. Here’s what we found.

Transparency Reports Are Few and Far Between

Companies should provide transparency reports of how often they provide data to the government, including information about whether it’s an official demand or an unofficial request. We have been calling on tech companies to publish transparency reports for a long time, but the practice is still rare across the industry. That’s especially true with fitness gadgets. 

Only two of the companies we surveyed, Apple and Google (which also owns Fitbit), currently publish transparency reports. Apple, Google, and Whoop promise to notify users of law enforcement requests in publicly available documentation. 

Oura now does too, after an update to their privacy policy in June 2026 that was perhaps prompted by a series of requests from journalist Zack Whittaker. In that same update and in an email to us, Oura promises that it is “actively evaluating ways to provide greater visibility into how we handle these requests, like through a transparency report.” This is promising, and we hope the company agrees that transparency reports are the best option moving forward. 

Any company that handles data that’s of interest to law enforcement and governments owes it to their users to publish transparency reports and, when legally possible, notify users when that data is requested.

Similarly, Suunto does not currently publish transparency reports, but in an email reply to our questions the company did express an openness to potentially doing so, stating, “We continuously evaluate our transparency practices and may publish additional information, such as a transparency report, in the future if we believe it would provide meaningful value for users and support our data protection efforts.” We hope they do, as these sorts of reports are a useful metric for all of us to better understand if and when our data can potentially be accessed by law enforcement.

We could not find instances where the other companies publicly state a policy around notification or transparency reports, and no others replied to our email questions.

Any company that handles data that’s of interest to law enforcement and governments owes it to their users to publish transparency reports and, when legally possible, notify users when that data is requested. This is especially true of personal health data, which can reveal our movements, and be used to infer details about what we’re doing at any given moment.

End-to-End Encrypted Data Is Far Too Rare of a Feature

End-to-end encryption is a method to ensure that your personal data is only accessible by you, and not the company who makes the device and manages the cloud storage. End-to-end encryption is usually used to refer to message encryption in communication apps, like Signal or WhatsApp, but can also refer to data storage. For example, many password managers use end-to-end encryption, and Ring implemented it for its cameras after we pushed for it. There’s no reason it can’t be offered for wearables too.

In the case of health data from wearable devices, it’s a way to store data in the cloud so that information can be synced and backed up between your device and an app on your phone in a way where only your devices can access it. 

Support for end-to-end encryption is more rare than transparency reports. 

The Apple Watch, at least with data that’s stored in the Health app, is the only popular fitness wearable that supports end-to-end encryption, and it’s enabled by default for all users (you are required to have two-factor authentication enabled as well, but that is also on by default for most accounts).

However, Apple Watch owners should remember that this protection is only for data stored in the Apple Health app. If you use other apps on your watch, or choose to share data with third-parties, like Strava, or if you’re sharing data with other wearables, like an Oura ring, that data is likely not end-to-end encrypted by the third-party company. 

Support for end-to-end encryption is more rare than transparency reports. 

And that’s it. Apple is the only one. No other popular consumer health wearable offers end-to-end encryption for the data it collects and stores online. Not Google. Not Garmin. Not Oura. Most of these companies instead offer encryption in transit and at rest, but this means those companies can still see and use your data. This is the industry standard, but it doesn’t have to be.

Another option would be more robust local-storage options. Some devices we looked at, like a handful of Garmin and Polar watches, can operate on the watch itself without syncing data to the cloud, but some models are limited in capability and cannot sync to an app without storing data online. More robust options for limiting the data to just the wearable and the phone app it's synced to would be a privacy improvement. For example, the Apple Watch has the option to disable iCloud sharing in Apple Health, which will keep the data only on your phone. It’s the only wearable we found that offers this feature without using a third-party app like Gadgetbridge or by physically connecting the wearable to a computer with a USB cable and transferring activity files over manually.

The general lack of local-only options or end-to-end encryption is a major privacy oversight, especially when you consider these devices collect heart rate, track sleep, and can log your location while also calculating a variety of health metrics supposedly intuiting everything from anxiety to your fitness “age.”

We understand that it’s technically more difficult to implement end-to-end encryption than other sorts of cloud storage, and comes with some limitations that may affect a user’s experience with a product. It also makes certain types of AI-related features harder to implement, since they’d typically need to work on-device (either in the app or the wearable device itself). Because of that, we believe an option for end-to-end encryption or local-only storage of the data collected by a wearable is the least companies can do. This way, those who want to use these devices can do so with the choice to either accept some privacy risks, or choose a more locked down option.

What’s Next

If you’re a user of a fitness wearable from any of the companies we’ve reached out to, or any other one, don’t be shy in asking for these sorts of features. In the rare cases a company offers a feature request page, use it—like for Garmin, Polar, Suunto, and Whoop. And when those types of outlets aren’t offered, don’t shy away from general contact pages, like those offered by Amazfit and Oura, or on community subreddits.

The companies that make these wearables, whether they’re designed for fitness or health, need to improve. At the bare minimum, companies need to publish transparency reports detailing how often they receive requests from law enforcement and commit to notifying users whenever that happens. 

It’s also well past the time for more companies to offer end-to-end encryption for the health data they’re storing. We acknowledge that this may be a trade-off for some features, like social networking features, but it should be up to users to decide if they’re willing to make those trade-offs. This level of privacy is an appealing feature that benefits users in myriad ways and more companies can set themselves apart by committing to this level of privacy.

Health data is some of the most personal data we produce, and most wearables companies are behind the times when it comes to basic privacy practices and transparency. Now’s the time to improve those practices.

The effort to age gate the internet is back in Washington—and now it has a new name. Recently passed by the House of Representatives, the KIDS Act is a sprawling package of proposals to control what we can see and say online. Supporters claim the KIDS Act is needed to protect minors online. But if lawmakers really want to make the internet safer, why are they encouraging more surveillance instead of protecting our privacy? We dive into this question with our EFFector newsletter.

JOIN OUR NEWSLETTER

For over 35 years, EFFector has been your guide to understanding the intersection of technology, civil liberties, and the law. This issue covers a victory for location privacy in the Supreme Court, disturbing developments in the militarization of domestic drones, and a controversial Congressional bill to control what we can see and say online.

Prefer to listen in? EFFector is now available on all major podcast platforms. This time, we're chatting with EFF Senior Policy Analyst Joe Mullin on what would happen to the open internet if the KIDS Act becomes law. You can find the episode and subscribe on your podcast platform of choice:

%3Ciframe%20height%3D%22200px%22%20width%3D%22100%25%22%20frameborder%3D%22no%22%20scrolling%3D%22no%22%20seamless%3D%22%22%20src%3D%22https%3A%2F%2Fplayer.simplecast.com%2F4e65dc91-33af-4dd4-ae88-1c8626b39537%3Fdark%3Dfalse%22%20allow%3D%22autoplay%22%3E%3C%2Fiframe%3E Privacy info. This embed will serve content from simplecast.com

   

Want to protect your right to online anonymity and access to the open web? Sign up for EFF's EFFector newsletter for updates, ways to take action, and new merch drops. You can also fuel the fight for privacy and free speech online when you support EFF today!

Concrete is the most widely used building material on Earth, and producing it is one of the largest single sources of carbon emissions. One promising way to reduce its environmental footprint is to 3D-print concrete, laying it down bead by bead like a giant icing-piping robot. This process eliminates the labor-intensive formwork of pouring it into molds, and places the material only where a structure needs it.

But many of the most efficient designs created by computers are impossible for today’s printers to build. Engineers use a technique called topology optimization to find the strongest structure that uses the least amount of material. But those mathematically ideal designs, with their intricate, spider-web shapes, don’t account for the physical limitations of large-scale concrete printers with their thick nozzles, limited turning, and need to print in one continuous motion.

Now a team of MIT researchers has developed a way to close that gap. Their framework, described in a new article in Additive Manufacturing, bakes a printer’s real fabrication limits directly into the optimization, so the design that comes out is one a machine can build and print with little or no manual redesign. They demonstrated it by designing, printing, and load-testing a 2.3-meter concrete bridge and found that today’s printing hardware, not the concrete itself, limits how light a structure can be.

“We were finding a lot of cracks you can fall through when it comes to translating these super-optimal designs into manufacturable designs,” says co-first author Hajin Kim-Tackowiak PhD ’26, a postdoc in MIT’s Department of Civil and Environmental Engineering (CEE). “Those cracks were like chasms.”

Designing for what can be built

To pin down the constraints, the team worked with the people who run the large-scale printing machines at Autodesk’s facility in Boston.

“They pointed at some of our sharp angles, and they went, 'I don't feel safe printing something like that,'” Kim-Tackowiak recalls.

Those conversations surfaced three key limitations: how thick each printed bead must be, how sharply the nozzle can turn, and the need to print in a single continuous line. The researchers translated each constraint directly into the mathematical rules of their framework.

Existing 3D-printed structures are typically produced with older methods that optimize the shape first, and then require “a massive amount of post-processing,” taking days to run, Kim-Tackowiak explains. By contrast, the team’s framework generated fully printable designs in about two minutes on a laptop. When the team needed to slightly reduce the bridge’s size on the day of printing, they simply reran the optimization and had an updated design five to 10 minutes later. 

“Reaching that speed at all is recent,” says co-first author Zane Schemmer, a PhD student in CEE. The math the method relies on, mixed-integer optimization, was long considered too hard to use. “You go back five, 10 years ago, the solver we used, even three years ago, could not solve these problems,” he says. “This field has been avoided, because everyone thinks that’s not an avenue we can go down. But with new algorithms and resources, it’s becoming a way we can start to frame problems.”

A bridge reveals the real limitation

To validate the framework, the researchers went back to Autodesk’s facility to print a 2.3-meter-long concrete bridge.

“The bridge took about 30 minutes to make and was built from off-the-shelf mortar,” says senior author Josephine Carstensen, the Gilbert W. Winslow (1937) Career Development Professor in Civil Engineering.

In testing, the roughly 900-pound structure held more than 2,000 pounds spread across it with virtually no measurable bending, closely matching the team’s simulations.

But the test also revealed the study’s biggest surprise. “What we found was our result was super over-engineered,” Kim-Tackowiak says. “From zero to 200,000 pounds, your design is entirely driven by these 'can I build it or not' constraints. And then, after 200,000 pounds, you can start to think about the physics.” In other words, the limits of current printing technology, not the strength of concrete, were dictating how efficient the structure could be.

A roadmap for better printers

Because the framework finds the mathematically best possible design, the researchers could measure exactly how much each hardware limitation costs in material.

“With mixed-integer optimization, we can find the global optimum, the best solution there is, as opposed to just a good solution,” Carstensen says. “Because we know we’re finding the best solution out there, we can also quantify: If we had a machine that could do other things, what would that mean for how much material we’re using?”

The single biggest lever was the width of the printed bead. The bridge used a 4 centimeter bead. The analysis showed a machine that was able to lay a 1cm bead could cut material use by as much as 76 percent while staying “well within safety margins,” Carstensen says. The result surprised her. “I thought the continuous path would be the problem, the one that had the highest effect,” she says. “But it wasn’t. It was the bead width.”

The result is a roadmap for printer-makers showing that modest hardware improvements could unlock large gains in efficiency and cut concrete’s carbon footprint.

Part of what made the bridge possible is that every piece is in compression. “With concrete, it’s really good when you push on it, really bad when you pull on it,” Schemmer says. “We're able to guarantee that every piece of concrete that you see is in compression, there’s no part that’s being pulled on.”

The savings come not only from using less material, but from skipping molds entirely, an advantage that grows for one-off shapes. Carstensen sees early promise in disaster relief, “You can quickly put up new infrastructure without needing to make formwork.”

The bridge’s compression-only nature showed itself dramatically after testing. It had held more than 2,000 pounds without budging, but when a worker lifted one corner a few inches to sweep beneath it, it broke. The failure wasn’t a design flaw so much as a demonstration of the principle behind it: Concrete is weak when pulled, and the lift put parts of the bridge in tension they were never meant to carry. “It’s optimal in one way, but it’s definitely not optimal in every way,” Kim-Tackowiak says.

That points to the team’s next step of reinforced concrete. “We know a pure concrete structure is not necessarily going to be the most optimal thing, so we’re moving it more into the world we live in today, which is reinforced concrete,” Kim-Tackowiak says, “though working out how to feed rebar into a printed concrete structure,” she adds, “is proving its own challenge.”

The work was funded by the National Science Foundation and supported by the MIT Center for Advanced Production Technologies. Joining Kim-Tackowiak, Schemmer, and Carstensen on the paper are co-authors Pittipat Wongsittikan, a PhD student in the MIT Building Technology Architecture program, and Jackson Jewett MEng ’18, PhD ’25, a former MIT postdoc.

It’s a fact of life that the electrical activity of neurons will vary during repetitions of the same task, even when the ultimate outcome is the same. A new study shows that a lot of ongoing fluctuations in the brain’s activity could be explained by the influence local electric fields exerted on the neurons, a phenomenon called “ephaptic coupling.” The finding, published in Cerebral Cortex, adds to evidence that the brain’s electric fields act as important control signals for underlying brain function.

“The brain is a rollicking sea of electrical influences,” says study co-author Earl K. Miller, Picower Professor of Neuroscience in The Picower Institute for Learning and Memory and MIT’s Department of Brain and Cognitive Sciences. “But the traditional view of brain function focuses only on the spiking and synaptic connections among individual neurons. Now, there is growing evidence for electric field effects. For instance, in this study we show that neural variability is explained by how ephaptic effects are influencing neural activity.”

In 2022 and 2023, Miller and fellow author Dimitris Pinotsis, associate professor at City St George’s, University of London, published several studies showing that local electric fields in the brain’s cortex not only reflected the information neurons were processing better than any individual neuron did, but also that the fields actively helped to organize the underlying neural spiking that executes that processing. Like an orchestra conductor, the electric waves can conduct crowds of neurons so that they are “playing the same tune.” They further theorize that fields physically exert influence on the structure of the brain via cytoelectric coupling, in which the fields alter the cytoskeleton of neurons, optimizing them to oscillate in synchrony.

Because electric fields can be manipulated, Miller and Pinotsis argue in the new study that understanding how they influence momentary brain function could open the door to therapeutic interventions designed to improve it when it is faltering in disease. It would be difficult to adjust every neural connection, but ephaptic coupling suggests that intervening at the level of electric fields could accomplish that therapeutic end, the researchers say.

“Properly devised electric field manipulations could help patients rewire faulty circuits,” Pinotsis and Miller wrote.

In the duo’s prior studies, they analyzed signals averaged over time, documenting that in general, even though local (or “mesoscale”) electric fields in the cortex arise from the electrical activity of individual neurons, the field ultimately represents and coordinates their function. Think of it this way: Neurons are like individual citizens, and the electric fields are their government. Once the citizens establish a government with their individual votes, they are then subject to and unified by the laws the government creates and enforces. 

In the new study, the team asked whether mesoscale electric fields not only provide this ephaptic influence overall during working memory tasks, but also trial by trial. After all, that’s closer to the timescale of actual brain operations that matter both for healthy function and in disease. 

So the scientists looked anew at the data they recorded as animals played a simple video game. The animals were shown a dot in one of six positions around a screen. After the dot disappeared, the animals had to hold its former position in memory because to succeed in the game and earn a reward, they had to glance when cued to indicate the direction where the dot had appeared. Meanwhile, the scientists recorded neural electrical spiking and more collective local field potentials. Using that information, they calculated the local prevailing electric field at each moment.

In their statistical analysis of the data, they made several findings. One, as expected, was that neural activity varied sometimes quite widely trial by trial during the task. Another, using a mathematical technique called Granger Causality, showed that the direction of influence between the electric field and the neural activity was strongly in favor of the field. In other words, in the coupling between the two, the fields were dominant.

“We found that electric fields that emerge from neural activity, captured with LFPs [local field potentials], turn around and influence this activity in a top-down fashion (ephaptic coupling),” the researchers wrote.

Moreover, the team’s modeling and calculations showed that the strength of the ephaptic coupling between the field and the neural activity was proportional to the variations in the LFP power — another sign that the fields influenced the neural activity.

“The larger the variability, the more evident the top-down organizing effects,” the researchers wrote. “The emerging picture is that electric fields serve as control parameters.”

The U.K. Medical Council, the U.S. Army Research Office, the U.S. Office of Naval Research, the Freedom Together Foundation, and the Picower Institute funded the study.

A high-fat, low-carbohydrate diet, also called a ketogenic diet, can help some people lose weight by forcing their bodies to burn fat for fuel instead of sugar. 

In recent years, scientists have been exploring how this type of diet might affect other aspects of health and disease, including cancer. While some research has shown that the diet may protect against the development of colon cancer, a new study by MIT researchers suggests that in the small intestine, a ketogenic diet may increase the risk of cancer.

“Ketogenic diets have distinct effects on different tissues even within the gastrointestinal tract. I think the message here is that we need to be very careful in generalizing the effects that these diets can have, because what might be beneficial for one tissue may be detrimental for another tissue,” says Omer Yilmaz, director of the MIT Stem Cell Initiative, an associate professor of biology at MIT, and a member of MIT’s Koch Institute for Integrative Cancer Research.

Yilmaz is the senior author of the study, which appears today in Nature. MIT postdocs Jessica Shay and Fangtao Chi are the lead authors of the paper. Researchers from the labs of Alex K. Shalek, director of MIT’s Institute for Medical Engineering and Science, and Matthew Vander Heiden, director of the Koch Institute, also contributed to the study.

Diet and cancer

Ketogenic diets, originally developed in the 1920s as a way to treat epilepsy, have been adapted in the past few decades as a strategy to lose weight or increase lifespan. The diet comprises a high percentage of fat, low percentage of carbohydrates, and normal or reduced amounts of protein.

This type of diet forces the body to burn fatty acids for energy in place of carbohydrates such as glucose. Burning these lipids produces ketone bodies — primarily β-hydroxybutyrate (BHB) and acetoacetate — as byproducts of fatty acid metabolism. These ketone bodies are also generated when people fast or follow very low-calorie diets, which force the body to burn its own fatty stores.

A 2022 Nature study suggested that ketogenic diets have a protective effect against colon cancer and that BHB — the most abundant ketone body — is responsible for this effect. In the new Nature study, the MIT team wanted to explore whether ketogenic diets might have a similar protective effect in the small intestine.

The researchers fed mice who were genetically predisposed to developing intestinal cancer either a ketogenic diet, a control diet, or a high fat/high calorie diet. They found that mice on a ketogenic diet were more likely to develop tumors of the small intestine than those on a control diet. While they did not become obese, mice on the ketogenic diet developed tumors at rates similar to or even higher than those of mice on an obesogenic high fat/high calorie diet. 

Additional studies revealed that ketone bodies did not play a role in tumor development. Instead, tumor growth was driven by how intestinal cells burn dietary fat for energy — a metabolic pathway called fatty acid oxidation. This pathway activates a family of proteins called PPARs, which signal stem cells to multiply more rapidly, increasing the chance that some become cancerous. 

This stem cell proliferation can be beneficial in certain situations, such as when the intestinal lining needs to be repaired after illness or injury. However, too much proliferation can tip cells toward becoming cancerous. 

“Having more stem cells means that when you injure the small intestine, it can repair itself better, but the downside is that having more active stem cells can lead to tumor formation,” Yilmaz says.

Opposite effects

Surprisingly, the same ketogenic diet that promoted tumors in the small intestine had the opposite effect in the colon. The researchers found, similar to the earlier Nature study back in 2022, that a ketogenic diet suppressed the development of colon tumors. However, the new findings suggest that ketone bodies are not responsible for this protective effect.

“Given how much attention has been paid to ketone bodies like BHB, both as a commercial health trend and in recent high-profile studies suggesting BHB suppresses colon cancer, we fully expected them to be the direct drivers. Instead, our experiments in genetically engineered mice revealed that these molecules are essentially metabolic bystanders. The real surprise is that tumor acceleration is driven entirely by how stem cells process and burn the heavy influx of dietary fat itself,” Yilmaz says.

The researchers now hope to further study why ketogenic diets have such different effects in the colon and the small intestine. As ketogenic diets continue to gain popularity, understanding these tissue-specific effects will be critical for guiding their use, the researchers say.

“The deeper question is why the same diet has opposite consequences in two adjacent parts of the gut. That is what we are working to understand next,” Chi says.

The findings carry practical implications. Because the diet’s effects — both the tumor acceleration in the small intestine and the protection in the colon — are driven entirely by fat metabolism rather than the ketones themselves, commercial ketone supplements or drinks would not be expected to mimic either the risks or the benefits discovered in this study. This may be especially relevant given that small intestinal tumors have been rising in incidence in recent decades, with the greatest impact on patients with inherited conditions that predispose them to intestinal cancer, such as familial adenomatous polyposis.

The research was funded, in part, by the National Institutes of Health, a Pew-Stewart Trust scholar award, the Kathy and Curt Marble cancer research award, a Koch Institute-Dana Farber/Harvard Cancer Center Bridge project grant, the American Federation for Aging Research, the MIT Stem Cell Initiative, a Damon Runyon Postdoctoral Research Fellowship, and the Koch Institute Support (core) grant from the National Cancer Institute.

Amazing:

Researchers from ETH Zurich in Switzerland, however, managed to create a new type of pixel that can simultaneously do both. This hypercharged pixel, called a Fourier pixel, can generate and sense arbitrary light fields and tap into a pixel’s full potential for carrying information by manipulating light’s intensity, oscillation phases, and polarization. The team reported its findings in a paper published yesterday in Nature.

We are one step closer to 1984 technology:

The telescreen received and transmitted simultaneously. Any sound that Winston made, above the level of a very low whisper, would be picked up by it; moreover, so long as he remained within the field of vision which the metal plaque commanded, he could be seen as well as heard. There was of course no way of knowing whether you were being watched at any given moment...

Justice Elena Kagan's foreword to a judicial reference manual has triggered calls for her to bow out of an upcoming Supreme Court case.

Companies peddling smoke-spotting cameras, firefighting drones and forest-clearing robots are taking their pitch from California to the Capitol.

The National Academies report has been the subject of intense scrutiny by energy industry allies ahead of its release.

The rapid growth could prompt countries like the U.S. to enact new barriers to development, according to a new report.

Artificial intelligence models sort through huge amounts of satellite data to help detect leaks.

Widespread adoption of the fuel in shipping could lead to a substantial reduction in global emissions.

The sustained demand reflects a global search for alternative energy sources that has been hastened by the energy-supply crunch arising from the Middle East war.

The deal will create one of Europe's biggest integrated direct air capture companies.

Heavy monsoon rains also triggered landslides that blocked several roads and damaged homes in the Gilgit-Baltistan region.

Nature Climate Change, Published online: 15 July 2026; doi:10.1038/s41558-026-02709-7

The authors demonstrate asymmetrical impacts of forest gain and loss on evapotranspiration and precipitation: gain increases the processes more than loss reduces them. They highlight a need to better consider hydrological asymmetry in climate models and in planning of forest-based climate solutions.

One of the best bulwarks against monopoly is interoperability—that is making a new product or service work with an existing product or service. Interoperability allows users, and not the manufacturers of their devices or largest player in a market, to decide what application best serves them. Unsurprisingly, companies like Apple have worked hard to resist interoperability requirements. 

On July 8, the General Court of the  European Union (General Court) ruled against Apple in several cases the company brought against the European Commission (joint cases), affirming the company’s obligations under the Digital Markets Act (DMA). Apple argued in the cases that it should be exempted from the law’s requirements especially with regards to interoperability on multiple grounds. We applaud the General Court’s  decision, and congratulate the Free Software Foundation Europe (FSFE) as well as others who intervened in support of the Commission against Apple's attempt to shirk off its responsibilities, thus ensuring fair competition in European markets.

A Positive Development for Europeans

This is a clear and substantive win for developers and users in Europe. The stranglehold Apple exerts over its ‘walled garden’ is injurious for developers, users, and researchers alike. By confirming Apple’s obligations under the DMA, the General Court has ensured that developers will be given more choice on where they can publish their apps, and users will have more options to obtain apps which, for whatever reason, Apple dislikes. And researchers will have less roadblocks and hurdles to overcome in their studies of Apple’s OSes, particularly iOS, iPadOS, and watchOS.

Apple argues that the interoperability requirements will force it to lower the security standards that have led Apple products’ users to trust their devices. While this self-serving logic is not entirely without merit, it is far from the inevitable outcome. Especially with regards to the App Store, users can be given clear, informed choice when leaving the Apple ecosystem to obtain apps elsewhere. While we urge European courts to take Apple’s security concerns seriously, we’ve previously noted that this should not be used as a smokescreen to protect anticompetitive behavior.

Interoperability and security are not inherently at odds. When interoperable functionality is worked into the security model of a platform from the ground-up, a proper balance can be struck between two forces that are often falsely framed as naturally conflicting. While Apple OS platforms have not been built this way from the get-go, it is still possible, but takes more time to get it right. Here, the devil is in the implementation details.

Apple’s Case Arguments and the Court’s Rebuttal

Under the DMA, designation as a ‘gatekeeper’ is reserved for the biggest of Big Tech, companies that provide services deemed essential for businesses to reach end users. Apple is one of only seven companies that meet this designation, along with Alphabet, Amazon, Booking, ByteDance, Meta, and Microsoft. In its case, Apple argued that Article 6(7) of the DMA, specifying interoperability requirements for gatekeepers aimed at restoring fair competition, is unlawful in light of the Charter of Fundamental Rights of the European Union (specifically the right to property), and as such its designation as a gatekeeper subject to the requirements is unlawful and should be annulled as a result. In its ruling, the General Court rejected the argument as Article 6(7) does not form the legal basis of the designation.

Apple separately argues that the App Store fails to meet the requirements defining a core platform service (CPS), since the various stores (across iOS, iPadOS, watchOS, macOS) do not constitute a single platform. A company’s gatekeeper status relies on it providing a CPS that is an important gateway for business users to reach end users. Here, the implications of the argument are clear: remove service designation as CPSes, remove the gatekeeper status. The court rejected the argument on the basis that “irrespective of the device on which it was available, each of the App Stores was used for the same purpose, namely to intermediate between end users and business users in the distribution of applications and in-app digital content.”

Finally, the court rejected as inadmissible Apple’s argument that iMessage should not be classified as a number-independent interpersonal communication service (NIICS) constituting a CPS. This decision rested on the fact that the “classification does not, by itself, produce binding legal effects that bring about a change in Apple’s legal position” since iMessage was not listed as an “important gateway” in the designation decision and therefore was not subject to the DMA obligations.

In ruling against Apple in favor of the European Commission, the General Court has set an important precedent in ensuring competitive fairness and openness in the digital marketplace. The landmark effects of the DMA will serve to benefit all Europeans in the choice and freedom it affords them. Despite Big Tech’s legal challenges, these decisions build a strong foundation for a better digital future—a lesson which other regions should learn from and take note.

Systems using artificial intelligence to enhance forecasting, planning, and decision-making in businesses have been proliferating in recent years, but in many cases, they lack the detailed, specific information about the organization itself, limiting the usefulness of those tools. 

Devavrat Shah, a principal investigator at MIT’s Laboratory for Information and Decision Systems (LIDS), faculty member with the department of Electrical Engineering and Computer Science (EECS), and member of the Institute for Data, Systems, and Society (IDSS), has been focused on how to design methods that can handle second-by-second decision-making using limited computational resources. 

“In a sense, with a small amount of resource, you have to do a lot of heavy lifting,” he says. As a researcher, “my interest is in the ability to develop methods that can extract information from data at scale in as effective a manner as possible.”

The Andrew (1956) and Erna Viterbi Professor has been teaching at MIT since 2005. 

In 2019, he also co-founded a spinoff company called Ikigai Labs. Ikigai built a foundation model for tabular, time series data based on years of research in Shah’s lab, which was patented and licensed by MIT to the company. This model can take input from enterprise data from varied sources, continuously and at scale, so that it learns as it goes along by testing its predictions against real outcomes.

Shah explains that the system is an extension of the kind of graphical models that are used, for example, by GPS devices to convert a sparse amount of data received from satellites into an accurate model of a position on the Earth’s surface, or by communication system like that in a digital watch that communicates at high speed in an energy-efficient manner. 

“My interest was: How does one design such graphical models for generic, tabular data?” he says.

While most AI models have been taught using text and images, this system takes tabular data as its input — structured data such as the familiar kind of row-and-column format used in spreadsheets. And then it provides the kind of real-time planning, on a vastly larger scale. 

The idea for Ikigai was to provide forecasting and decision-making technology for large businesses, such as consumer goods manufacturers and pharmaceutical companies.

Shah gives the example of how a consumer electronics company might use this system. 

“Let’s say you’re making headphones and all sorts of different things. And each of the products that you manufacture has lots of small pieces that come from different parts of the world. And once the device is sold, it needs to be supported and maintained. And you have to come up with new versions of the product, you have to market them, you have to price them … So the questions you would typically ask would be: If I were to sell these next quarter or next year, how many will be sold in different places, and what would happen to demand if I change the price, or if I introduce promotion?”

He adds that all of these processes are interdependent, and at every stage of the processes decisions have to be made that have implications over time. “At some level,” he says, “digitizing these processes and being able to do predictions and constantly optimize is what leads to ultimately better business operations.”

Ikigai was recently acquired by the international firm Celonis, where Shah is now chief scientist in addition to his roles at MIT. Ultimately, he hopes the model he developed for Ikigai will help Celonis deliver tools that can integrate with a company’s own data and business processes in order to provide real-world analyses that can help make forecasts, plans, and decisions.

Shah adds that Celonis has specialized in digitizing and automating operations for more than 1,400 large companies around the world. Now that these systems are fully digitized, they provide a platform for Ikigai’s software to take the next step, reading the data from these digitized systems in order to provide detailed models to allow simulation of different options, predict optimum strategies, and forecast the results of a given set of decisions. 

“Once the digital layer of these processes exists and this information layer exists,” Shah says, “now, on top of it, we can put the Ikigai stack to enable decision-making at a much larger scale than otherwise.”

While so many companies are working on various aspects of AI, “we are very much focused on part of the domain that the rest of the world is not paying attention to,” which is the area of structured or time-domain data. By starting from such data, he says, it provides a very cost-effective version of AI. 

“A narrower focus comes with sharper technology,” he says, “but it’s broad enough that it’s very valuable.”

Shah adds, “The recent buzzword that’s become pertinent in the modern AI popular press is a ‘world model.’ In a sense, this is trying to build the enterprise process world model, so to speak.”