Calorie restriction can help animals live longer. What about humans?

Living comes with a side effect: aging. Despite what you might hear on social media or in advertisements, there are no drugs that are known to slow or reverse human aging. But there’s some evidence to support another approach: cutting back on calories.

Caloric restriction (reducing your intake of calories) and intermittent fasting (switching between fasting and eating normally on a fixed schedule) can help with weight loss. But they may also offer protection against some health conditions. And some believe such diets might even help you live longer—a finding supported by new research out this week. (Longevity enthusiast Bryan Johnson famously claims to eat his last meal of the day at 12pm.)

But the full picture is not so simple. Weight loss isn’t always healthy and neither is restricting your calorie intake, especially if your BMI is low to begin with. Some scientists warn that, based on evidence in animals, it could negatively impact wound healing, metabolism and bone density. This week let’s take a closer look at the benefits—and risks—of caloric restriction.

Eating less can make animals live longer. This remarkable finding has been published in scientific journals for the last 100 years. It seems to work in almost every animal studied—everything from tiny nematode worms and fruit flies to mice, rats, and even monkeys. It can extend the lifespan of rodents by between 15% and 60%, depending on which study you look at.

The effect of caloric restriction is more reliable than the leading contenders for an “anti-aging” drug. Both rapamycin (an immunosuppressive drug used in organ transplants) and metformin (a diabetes drug) have been touted as potential longevity therapeutics. And both have been found to increase the lifespans of animals in some studies.

But when scientists looked at 167 published studies of those three interventions in research animals, they found that caloric restriction was the most “robust.” According to their research, published in the journal Aging Cell on Wednesday, the effect of rapamycin was somewhat comparable, but metformin was nowhere near as effective.

“That is a pity for the many people now taking off-label metformin for lifespan extension,” David Clancy, lecturer in biogerontology at Lancaster University, said in a statement. “Let’s hope it doesn’t have any or many adverse effects.” Still, for caloric restriction, so far so good.

At least it’s good news for lab animals. What about people? Also on Wednesday, another team of scientists published a separate review of research investigating the effects of caloric restriction and fasting on humans. That review assessed 99 clinical trials, involving over 6,500 adults. (As I said, caloric restriction has been an active area of research for a long time.)

Those researchers found that, across all those trials, fasting and caloric restriction did seem to aid weight loss. There were other benefits, too—but they depended on the specific approach to dieting. Fasting every other day seemed to help lower cholesterol, for example. Time-restricted eating, where you only eat within a specific period each day (à la Bryan Johnson), by comparison, seemed to increase cholesterol, the researchers write in the BMJ. Given that elevated cholesterol in the blood can lead to heart disease, it’s not great news for the time-restricted eaters.

Cutting calories could also carry broader risks. Dietary restriction seems to impair wound healing in mice and rats, for example. Caloric restriction also seems to affect bone density. In some studies, the biggest effects on lifespan extension are seen when rats are put on calorie-restricted diets early in life. But this approach can affect bone development and reduce bone density by 9% to 30%.

It’s also really hard for most people to cut their caloric intake. When researchers ran a two-year trial to measure the impact of a 25% reduction in caloric intake, they found that the most their volunteers could cut was 12%. (That study found that caloric restriction reduces markers of inflammation, which can be harmful when it’s chronic, and had only a small impact on bone density.)

Unfortunately, there’s a lot we still don’t really understand about caloric restriction. It doesn’t seem to help all animals live longer—it seems to shorten the lifespan of animals with certain genetic backgrounds. And we don’t know whether it extends the lifespan of people. It isn’t possible to conduct a randomized clinical trial in which you deprive people of food from childhood and then wait their entire lives to see when they die.

It is notoriously difficult to track or change your diet. And given the unknowns surrounding caloric restriction, it’s too soon to make sweeping recommendations, particularly given that your own personal biology will play a role in any benefits or risks you’ll experience. Roll on the next round of research.

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

Here’s what food and drug regulation might look like under the Trump administration

Earlier this week, two new leaders of the US Food and Drug Administration published a list of priorities for the agency. Both Marty Makary and Vinay Prasad are controversial figures in the science community. They were generally highly respected academics until the covid pandemic, when their contrarian opinions on masking, vaccines, and lockdowns turned many of their colleagues off them.

Given all this, along with recent mass firings of FDA employees, lots of people were pretty anxious to see what this list might include—and what we might expect the future of food and drug regulation in the US to look like. So let’s dive into the pair’s plans for new investigations, speedy approvals, and the “unleashing” of AI.

First, a bit of background. Makary, the current FDA commissioner, is a surgeon and was a professor of health policy at the Johns Hopkins School of Public Health. He initially voiced support for stay-at-home orders during the pandemic but later changed his mind. In February 2021, he incorrectly predicted that the US would “have herd immunity by April.” He has also been very critical of the FDA, writing in 2021 that its then leadership acted like “a crusty librarian” and that drug approvals were “erratic.”

Prasad, an oncologist, hematologist, and health researcher, was named director of the FDA’s Center for Biologics Evaluation and Research last month. He has long been a proponent of rigorous evidence-based medicine. When I interviewed him back in 2019, he told me that cancer drugs are often approved on the basis of weak evidence, and that they can end up being ineffective or even harmful. He has written a book arguing that drug regulators need to raise the bar of evidence for drug approvals. He was widely respected by his peers.

Things changed during the pandemic. Prasad made a series of contrarian comments; he claimed that the covid virus “was likely a lab leak” despite the fact that the vast majority of scientists believe that the virus jumped to humans from animals in a market. He railed against Anthony Fauci, and advised readers of his blog to “break all home Covid tests.” In 2023, he authored a post titled “Do not report Covid cases to schools & do not test yourself if you feel ill.” He has even drawn parallels between the US covid response and fascism in Nazi Germany. Suffice to say he’s lost the support of many of his fellow academics.

Makary and Prasad published their “priorities for a new FDA” in the Journal of the American Medical Association on Tuesday. (Funnily enough, JAMA is one of the journals that their boss, Robert F. Kennedy Jr., described as “corrupt” just a couple of weeks ago—one that he said he’d ban government scientists from publishing in. Lol.)

Let’s go through a few of the points the pair make in their piece. They open by declaring that the US medical system has been “a 50 year failure.” It’s true that the US spends a lot more on health care than other wealthy countries do, and yet has a lower life expectancy. And around 25 million Americans don’t have health insurance.

“In some ways, it is absolutely a failure,” says Christopher Robertson, a professor of health law at Boston University. “On the other hand, it’s the envy of the world [because] it’s very good at delivering high-end care.” Either way, the reasons for failures in health care are not really the scope of the FDA, which has a focus on ensuring the safety and efficacy of food and medicines.

Makary and Prasad then state that they want the FDA to “examine the role of ultraprocessed foods” as well as additives and environmental toxins, suggesting that all these may be involved in chronic diseases. This is a favorite talking point of RFK Jr., who has made similar promises about investigating a possible connection.

But this would also go beyond the current established purview of the FDA, says Robertson. There isn’t a clear, agreed-upon definition of “ultraprocessed food,” for a start, so it’s hard to predict what exactly would be included in any investigation. And as things stand, “the FDA’s role is primarily binary: They either allow or reject products,” adds Robertson. The agency doesn’t really give dietary advice.

Perhaps that could change. At his confirmation hearing, Makary told senators he planned to evaluate school lunches, seed oils, and food dyes. “Maybe three years from now the FDA will change and have much more of a food focus,” says Robertson.

The pair also write that they want to speed up the process of approving new drugs, which can currently take more than 10 years. Their suggestions include allowing drug developers to submit final paperwork early, while testing is still underway, and getting rid of “recipes” that strictly limit what manufacturers can put in infant formula.

Here’s where things get a little more controversial. Most new drugs fail. They might look very promising in cells in a dish, or even in animals. They might look safe enough in a small phase I study in humans. But after that, large-scale human studies reveal plenty of drugs to be either ineffective, unsafe, or both.

Speeding up the drug approval process might mean some of these failures aren’t noticed until a drug is already being sold and prescribed. Even preparing paperwork ahead of time might result in a huge waste of time and money for both drug developers and the FDA if that drug later fails its final round of testing, says Robertson.

And as for infant formula recipes, they are in place for a reason: because we know they’re safe. Loosening that requirement might allow for more innovation. It could lead to the development of better recipes. But, as Robertson points out, innovation is a double-edged sword. “Some innovation saves lives; some innovation kills people,” he says.

Along the same lines, the pair also advocate for reducing the number of clinical trials required for the FDA to approve a drug. Instead of two “pivotal” clinical trials, drugmakers might only need to complete one, they suggest.

This is also controversial. A drug might look promising in one clinical trial and fail in another. That was the case for aducanamab (Aduhelm), the Alzheimer’s drug that was approved by the FDA in 2021 despite the concerns of several senior officials. (Biogen, the company that developed the drug, abandoned it in 2024, and it was later withdrawn from the market.)

At any rate, the FDA has already implemented several pathways for “expedited approval.” The Accelerated Approval Program fast-tracks the process for drugs that treat serious conditions or fulfill an unmet need. (Side note: This approval pathway relies on the very kind of weak evidence that Prasad has campaigned against.)

The Fast Track Program serves a similar purpose. As does the Breakthrough Therapy designation. Some health researchers are worried that programs like these, along with other factors, are responsible for a gradual lowering of the bar of evidence for new drugs in the US. Calling for an acceleration of cures, as the authors do, isn’t really anything new.

Makary and Prasad also list artificial intelligence as a priority—specifically, generative AI. They write that “on May 8, 2025, the agency implemented the first AI-assisted scientific review pilot using the latest generative AI technology.” It’s not clear exactly which technology was used, or how. But this priority didn’t surprise Rachel Sachs, a professor of health law at Washington University in St. Louis.

“Both this administration and the previous administration were very interested in the use of AI technologies,” she says. She points out that as of last year, the FDA had already approved over a thousand medical devices that make use of AI and machine learning. And the agency has also been considering how it might use the technologies in its review process, she adds: “It’s not a new idea.”

There’s another sticking point. Writing a list of priorities in JAMA is one thing. Implementing them amid hugely disruptive and damaging cuts underway across federal health and science agencies is quite another.

Makary and Prasad have both made claims to the effect that they support “gold standard” science and have built their careers on extolling the virtues of evidence-based medicine. But it’s hard to square this position with the actions of the administration, including the huge budget cuts made to the National Institutes of Health, restrictions on government-funded research, and mass layoffs across multiple government health agencies, including the FDA. “It’s almost as if the two sides are talking past each other,” says Sachs.

As a result, it’s impossible to predict exactly what’s going to happen. We’ll have to wait to see how this all pans out.

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

The FDA plans to limit access to covid vaccines. Here’s why that’s not all bad.

This week, two new leaders at the US Food and Drug Administration announced plans to limit access to covid vaccines, arguing that there is not much evidence to support the value of annual shots in healthy people. New vaccines will be made available only to the people who are most vulnerable—namely, those over 65 and others with conditions that make them more susceptible to severe disease.

Anyone else will have to wait. Covid vaccines will soon be required to go through more rigorous trials to ensure that they really are beneficial for people who aren’t at high risk.

The plans have been met with fear and anger in some quarters. But they weren’t all that shocking to me. In the UK, where I live, covid boosters have been offered only to vulnerable groups for a while now. And the immunologists I spoke to agree: The plans make sense.

They are still controversial. Covid hasn’t gone away. And while most people are thought to have some level of immunity to the virus, some of us still stand to get very sick if infected. The threat of long covid lingers, too. Given that people respond differently to both the virus and the vaccine, perhaps individuals should be able to choose whether they get a vaccine or not.

I should start by saying that covid vaccines have been a remarkable success story. The drugs were developed at record-breaking speed—they were given to people in clinical trials just 69 days after the virus had been identified. They are, on the whole, very safe. And they work remarkably well. They have saved millions of lives. And they rescued many of us from lockdowns.

But while many of us have benefited hugely from covid vaccinations in the past, there are questions over how useful continuing annual booster doses might be. That’s the argument being made by FDA head Marty Makary and Vinay Prasad, director of the agency’s Center for Biologics Evaluation and Research.

Both men have been critical of the FDA in the past. Makary has long been accused of downplaying the benefits of covid vaccines. He made incorrect assumptions about the coronavirus responsible for covid-19 and predicted that the disease would be “mostly gone” by April 2021. Most recently, he also testified in Congress that the theory that the virus came from a lab in China was a “no-brainer.” (The strongest evidence suggests the virus jumped from animals to humans in a market in Wuhan.)

Prasad has said “the FDA is a failure” and has called annual covid boosters “a public health disaster the likes of which we’ve never seen before,” because of a perceived lack of clinical evidence to support their use.

Makary and Prasad’s plans, which were outlined in the New England Journal of Medicine on Tuesday, don’t include such inflammatory language or unfounded claims, thankfully. In fact, they seem pretty measured: Annual covid booster shots will continue to be approved for vulnerable people but will have to be shown to benefit others before people outside the approved groups can access them.

There are still concerns being raised, though. Let’s address a few of the biggest ones.

Shouldn’t I get an annual covid booster alongside my flu vaccine?

At the moment, a lot of people in the US opt to get a covid vaccination around the time they get their annual flu jab. Each year, a flu vaccine is developed to protect against what scientists predict will be the dominant strain of virus circulating come flu season, which tends to run from October through March.

But covid doesn’t seem to stick to the same seasonal patterns, says Susanna Dunachie, a clinical doctor and professor of infectious diseases at the University of Oxford in the UK. “We seem to be getting waves of covid year-round,” she says.

And an annual shot might not offer the best protection against covid anyway, says Fikadu Tafesse, an immunologist and virologist at Oregon Health & Science University in Portland. His own research suggests that leaving more than a year between booster doses could enhance their effectiveness. “One year is really a random time,” he says. It might be better to wait five or 10 years between doses instead, he adds.

“If you are at risk [of a serious covid infection] you may actually need [a dose] every six months,” says Tafesse. “But for healthy individuals, it’s a very different conversation.”

What about children—shouldn’t we be protecting them?

There are reports that pediatricians are concerned about the impact on children, some of whom can develop serious cases of covid. “If we have safe and effective vaccines that prevent illness, we think they should be available,” James Campbell, vice chair of the committee on infectious diseases at the American Academy of Pediatrics, told STAT.

This question has been on my mind for a while. My two young children, who were born in the UK, have never been eligible for a covid vaccine in this country. I found this incredibly distressing when the virus started tearing through child-care centers—especially given that at the time, the US was vaccinating babies from the age of six months.

My kids were eventually offered a vaccine in the US, when we temporarily moved there a couple of years ago. But by that point, the equation had changed. They’d both had covid by then. I had a better idea of the general risks of the virus to children. I turned it down.

I was relieved to hear that Tafesse had made the same decision for his own children. “There are always exceptions, but in general, [covid] is not severe in kids,” he says. The UK’s Joint Committee on Vaccination and Immunology found that the benefits of vaccination are much smaller for children than they are for adults.

“Of course there are children with health problems who should definitely have it,” says Dunachie. “But for healthy children in healthy households, the benefits probably are quite marginal.”

Shouldn’t healthy people get vaccinated to help protect more vulnerable members of society?

It’s a good argument, says Tafesse. Research suggests that people who are vaccinated against covid-19 are less likely to end up transmitting the infection to the people around them. The degree of protection is not entirely clear, particularly with less-studied—and more contagious—variants of the virus and targeted vaccines. The safest approach is to encourage those at high risk to get the vaccine themselves, says Tafesse.

If the vaccines are safe, shouldn’t I be able to choose to get one?

Tafesse doesn’t buy this argument. “I know they are safe, but even if they’re safe, why do I need to get one?” People should know if they are likely to benefit from a drug they are taking, he says.

Having said that, the cost-benefit calculation will differ between individuals. Even a “mild” covid infection can leave some people bed-bound for a week. For them, it might make total sense to get the vaccine.

Dunachie thinks people should be able to make their own decisions. “Giving people a top-up whether they need it or not is a safe thing to do,” she says.

It is still not entirely clear who will be able to access covid vaccinations under the new plans, and how. Makary and Prasad’s piece includes a list of “medical conditions that increase a person’s risk of severe covid-19,” which includes several disorders, pregnancy, and “physical inactivity.” It covers a lot of people; research suggests that around 25% of Americans are physically inactive.

But I find myself agreeing with Dunachie. Yes, we need up-to-date evidence to support the use of any drugs. But taking vaccines away from people who have experience with them and feel they could benefit from them doesn’t feel like the ideal way to go about it.

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

Access to experimental medical treatments is expanding across the US

A couple of weeks ago I was in Washington, DC, for a gathering of scientists, policymakers, and longevity enthusiasts. They had come together to discuss ways to speed along the development of drugs and other treatments that might extend the human lifespan.

One approach that came up was to simply make experimental drugs more easily accessible. Let people try drugs that might help them live longer, the argument went. Some groups have been pushing bills to do just that in Montana, a state whose constitution explicitly values personal liberty.

A couple of years ago, a longevity lobbying group helped develop a bill that expanded on the state’s existing Right to Try law, which allowed seriously ill people to apply for access to experimental drugs (that is, drugs that have not been approved by drug regulators). The expansion, which was passed in 2023, opened access for people who are not seriously ill. 

Over the last few months, the group has been pushing further—for a new bill that sets out exactly how clinics can sell experimental, unproven treatments in the state to anyone who wants them. At the end of the second day of the event, the man next to me looked at his phone. “It just passed,” he told me. (The lobbying group has since announced that the state’s governor Greg Gianforte has signed the bill into law, but when I called his office, Gianforte’s staff said they could not legally tell me whether or not he has.)

The passing of the bill could make Montana something of a US hub for experimental treatments. But it represents a wider trend: the creep of Right to Try across the US. And a potentially dangerous departure from evidence-based medicine.

In the US, drugs must be tested in human volunteers before they can be approved and sold. Early-stage clinical trials are small and check for safety. Later trials test both the safety and efficacy of a new drug.

The system is designed to keep people safe and to prevent manufacturers from selling ineffective or dangerous products. It’s meant to protect us from snake oil.

But people who are seriously ill and who have exhausted all other treatment options are often desperate to try experimental drugs. They might see it as a last hope. Sometimes they can volunteer for clinical trials, but time, distance, and eligibility can rule out that option.

Since the 1980s, seriously or terminally ill people who cannot take part in a trial for some reason can apply for access to experimental treatments through a “compassionate use” program run by the US Food and Drug Administration (FDA). The FDA authorizes almost all of the compassionate use requests it receives (although manufacturers don’t always agree to provide their drug for various reasons).

But that wasn’t enough for the Goldwater Institute, a libertarian organization that in 2014 drafted a model Right to Try law for people who are terminally ill. Versions of this draft have since been passed into law in 41 US states, and the US has had a federal Right to Try law since 2018. These laws generally allow people who are seriously ill to apply for access to drugs that have only been through the very first stages of clinical trials, provided they give informed consent.

Some have argued that these laws have been driven by a dislike of both drug regulation and the FDA. After all, they are designed to achieve the same result as the compassionate use program. The only difference is that they bypass the FDA.

Either way, it’s worth noting just how early-stage these treatments are. A drug that has been through phase I trials might have been tested in just 20 healthy people. Yes, these trials are designed to test the safety of a drug, but they are never conclusive. At that point in a drug’s development, no one can know how a sick person—who is likely to be taking other medicines— will react to it.

Now these Right to Try laws are being expanded even more. The Montana bill, which goes the furthest, will enable people who are not seriously ill to access unproven treatments, and other states have been making moves in the same direction.

Just this week, Georgia’s governor signed into law the Hope for Georgia Patients Act, which allows people with life-threatening illnesses to access personalized treatments, those that are “unique to and produced exclusively for an individual patient based on his or her own genetic profile.” Similar laws, known as “Right to Try 2.0,”  have been passed in other states, too, including Arizona, Mississippi, and North Carolina.

And last year, Utah passed a law that allows health care providers (including chiropractors, podiatrists, midwives, and naturopaths) to deliver unapproved placental stem cell therapies. These treatments involve cells collected from placentas, which are thought to hold promise for tissue regeneration. But they haven’t been through human trials. They can cost tens of thousands of dollars, and their effects are unknown. Utah’s law was described as a “pretty blatant broadbrush challenge to the FDA’s authority” by an attorney who specializes in FDA law. And it’s one that could put patients at risk.

Laws like these spark a lot of very sensitive debates. Some argue that it’s a question of medical autonomy, and that people should have the right to choose what they put in their own bodies.

And many argue there’s a cost-benefit calculation to be made. A seriously ill person potentially has more to gain and less to lose from trying an experimental drug, compared to someone who is in good health.

But everyone needs to be protected from ineffective drugs. Most ethicists think it’s unethical to sell a treatment when you have no idea if it will work, and that argument has been supported by numerous US court decisions over the years. 

There could be a financial incentive for doctors to recommend an experimental drug, especially when they are granted protections by law. (Right to Try laws tend to protect prescribing doctors from disciplinary action and litigation should something go wrong.)

On top of all this, many ethicists are also concerned that the FDA’s drug approval process itself has been on a downward slide over the last decade or so. An increasing number of drug approvals are fast-tracked based on weak evidence, they argue.

Scientists and ethicists on both sides of the debate are now waiting to see what unfolds under the new US administration.  

In the meantime, a quote from Diana Zuckerman, president of the nonprofit National Center for Health Research, comes to mind: “Sometimes hope helps people do better,” she told me a couple of years ago. “But in medicine, isn’t it better to have hope based on evidence rather than hope based on hype?”

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

Your gut microbes might encourage criminal behavior

A few years ago, a Belgian man in his 30s drove into a lamppost. Twice. Local authorities found that his blood alcohol level was four times the legal limit. Over the space of a few years, the man was apprehended for drunk driving three times. And on all three occasions, he insisted he hadn’t been drinking.

He was telling the truth. A doctor later diagnosed auto-brewery syndrome—a rare condition in which the body makes its own alcohol. Microbes living inside the man’s body were fermenting the carbohydrates in his diet to create ethanol. Last year, he was acquitted of drunk driving.

His case, along with several other scientific studies, raises a fascinating question for microbiology, neuroscience, and the law: How much of our behavior can we blame on our microbes?

Each of us hosts vast communities of tiny bacteria, archaea (which are a bit like bacteria), fungi, and even viruses all over our bodies. The largest collection resides in our guts, which play home to trillions of them. You have more microbial cells than human cells in your body. In some ways, we’re more microbe than human.

Microbiologists are still getting to grips with what all these microbes do. Some seem to help us break down food. Others produce chemicals that are important for our health in some way. But the picture is extremely complicated, partly because of the myriad ways microbes can interact with each other.

But they also interact with the human nervous system. Microbes can produce compounds that affect the way neurons work. They also influence the functioning of the immune system, which can have knock-on effects on the brain. And they seem to be able to communicate with the brain via the vagus nerve.

If microbes can influence our brains, could they also explain some of our behavior, including the criminal sort? Some microbiologists think so, at least in theory. “Microbes control us more than we think they do,” says Emma Allen-Vercoe, a microbiologist at the University of Guelph in Canada.

Researchers have come up with a name for applications of microbiology to criminal law: the legalome. A better understanding of how microbes influence our behavior could not only affect legal proceedings but also shape crime prevention and rehabilitation efforts, argue Susan Prescott, a pediatrician and immunologist at the University of Western Australia, and her colleagues.

“For the person unaware that they have auto-brewery syndrome, we can argue that microbes are like a marionettist pulling the strings in what would otherwise be labeled as criminal behavior,” says Prescott.

Auto-brewery syndrome is a fairly straightforward example (it has been involved in the acquittal of at least two people so far), but other brain-microbe relationships are likely to be more complicated. We do know a little about one microbe that seems to influence behavior: Toxoplasmosis gondii, a parasite that reproduces in cats and spreads to other animals via cat feces.

The parasite is best known for changing the behavior of rodents in ways that make them easier prey—an infection seems to make mice permanently lose their fear of cats. Research in humans is nowhere near conclusive, but some studies have linked infections with the parasite to personality changes, increased aggression, and impulsivity.

“That’s an example of microbiology that we know affects the brain and could potentially affect the legal standpoint of someone who’s being tried for a crime,” says Allen-Vercoe. “They might say ‘My microbes made me do it,’ and I might believe them.”

There’s more evidence linking gut microbes to behavior in mice, which are some of the most well-studied creatures. One study involved fecal transplants—a procedure that involves inserting fecal matter from one animal into the intestines of another. Because feces contain so much gut bacteria, fecal transplants can go some way to swap out a gut microbiome. (Humans are doing this too—and it seems to be a remarkably effective way to treat persistent C. difficile infections in people.)

Back in 2013, scientists at McMaster University in Canada performed fecal transplants between two strains of mice, one that is known for being timid and another that tends to be rather gregarious. This swapping of gut microbes also seemed to swap their behavior—the timid mice became more gregarious, and vice versa.

Microbiologists have since held up this study as one of the clearest demonstrations of how changing gut microbes can change behavior—at least in mice. “But the question is: How much do they control you, and how much is the human part of you able to overcome that control?” says Allen-Vercoe. “And that’s a really tough question to answer.”

After all, our gut microbiomes, though relatively stable, can change. Your diet, exercise routine, environment, and even the people you live with can shape the communities of microbes that live on and in you. And the ways these communities shift and influence behavior might be slightly different for everyone. Pinning down precise links between certain microbes and criminal behaviors will be extremely difficult, if not impossible. 

“I don’t think you’re going to be able to take someone’s microbiome and say ‘Oh, look—you’ve got bug X, and that means you’re a serial killer,” says Allen-Vercoe.

Either way, Prescott hopes that advances in microbiology and metabolomics might help us better understand the links between microbes, the chemicals they produce, and criminal behaviors—and potentially even treat those behaviors.

“We could get to a place where microbial interventions are a part of therapeutic programming,” she says.

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

Longevity clinics around the world are selling unproven treatments

The quest for long, healthy life—and even immortality—is probably almost as old as humans are, but it’s never been hotter than it is right now. Today my newsfeed is full of claims about diets, exercise routines, and supplements that will help me live longer.

A lot of it is marketing fluff, of course. It should be fairly obvious that a healthy, plant-rich diet and moderate exercise will help keep you in good shape. And no drugs or supplements have yet been proved to extend human lifespan.

The growing field of longevity medicine is apparently aiming for something in between these two ends of the wellness spectrum. By combining the established tools of clinical medicine (think blood tests and scans) with some more experimental ones (tests that measure your biological age), these clinics promise to help their clients improve their health and longevity.

But a survey of longevity clinics around the world, carried out by an organization that publishes updates and research on the industry, is revealing a messier picture. In reality, these clinics—most of which cater only to the very wealthy—vary wildly in their offerings.

Today, the number of longevity clinics is thought to be somewhere in the hundreds. The proponents of these clinics say they represent the future of medicine. “We can write new rules on how we treat patients,” Eric Verdin, who directs the Buck Institute for Research on Aging, said at a professional meeting last year.

Phil Newman, who runs Longevity.Technology, a company that tracks the longevity industry, says he knows of 320 longevity clinics operating around the world. Some operate multiple centers on an international scale, while others involve a single “practitioner” incorporating some element of “longevity” into the treatments offered, he says. To get a better idea of what these offerings might be, Newman and his colleagues conducted a survey of 82 clinics around the world, including the US, Australia, Brazil, and multiple countries in Europe and Asia.

Some of the results are not all that surprising. Three-quarters of the clinics said that most of their clients were Gen Xers, aged between 44 and 59. This makes sense—anecdotally, it’s around this age that many people start to feel the effects of aging. And research suggests that waves of molecular changes associated with aging hit us in our 40s and again in our 60s. (Longevity influencers Bryan Johnson, Andrew Huberman, and Peter Attia all fall into this age group too.)

And I wasn’t surprised to see that plenty of clinics are offering aesthetic treatments, focusing more on how old their clients look. Of the clinics surveyed, 28% said they offered Botox injections, 35% offered hair loss treatments, and 38% offered “facial rejuvenation procedures.”  “The distinction between longevity medicine and aesthetic medicine remains blurred,” Andrea Maier of the National University of Singapore, and cofounder of a private longevity clinic, wrote in a commentary on the report.

Maier is also former president of the Healthy Longevity Medicine Society, an organization that was set up with the aim of establishing clinical standards and credibility for longevity clinics. Other results from the survey underline how much of a challenge this will be; many clinics are still offering unproven treatments. Over a third of the clinics said they offered stem-cell treatments, for example. There is no evidence that those treatments will help people live longer—and they are not without risk, either.

I was a little surprised to see that most of the clinics are also offering prescription medicines off label. In other words, drugs that have been approved for specific medical issues are apparently being prescribed for aging instead. This is also not without risks—all medicines have side effects. And, again, none of them have been proved to slow or reverse human aging.

And these prescriptions are coming from certified medical doctors. More than 80% of clinics reported that their practice was overseen by a medical doctor with more than 10 years of clinical experience.

It was also a little surprising to learn that despite their high fees, most of these clinics are not making a profit. For clients, the annual costs of attending a longevity clinic range between $10,000 and $150,000, according to Fountain Life, a company with clinics in Florida and Prague. But only 39% of the surveyed clinics said they were turning a profit and 30% said they were “approaching breaking even,” while 16% said they were operating at a loss.

Proponents of longevity clinics have high hopes for the field. They see longevity medicine as nothing short of a revolution—a move away from reactive treatments and toward proactive health maintenance. But these survey results show just how far they have to go.

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

“Spare” living human bodies might provide us with organs for transplantation

This week, MIT Technology Review published a piece on bodyoids—living bodies that cannot think or feel pain. In the piece, a trio of scientists argue that advances in biotechnology will soon allow us to create “spare” human bodies that could be used for research, or to provide organs for donation.

If you find your skin crawling at this point, you’re not the only one. It’s a creepy idea, straight from the more horrible corners of science fiction. But bodyoids could be used for good. And if they are truly unaware and unable to think, the use of bodyoids wouldn’t cross “most people’s ethical lines,” the authors argue. I’m not so sure.

Either way, there’s no doubt that developments in science and biotechnology are bringing us closer to the potential reality of bodyoids. And the idea is already stirring plenty of ethical debate and controversy.

One of the main arguments made for bodyoids is that they could provide spare human organs. There’s a huge shortage of organs for transplantation. More than 100,000 people in the US are waiting for a transplant, and 17 people on that waiting list die every day. Human bodyoids could serve as a new source.

Scientists are working on other potential solutions to this problem. One approach is the use of gene-edited animal organs. Animal organs don’t typically last inside human bodies—our immune systems will reject them as “foreign.” But a few companies are creating pigs with a series of gene edits that make their organs more acceptable to human bodies.

A handful of living people have received gene-edited pig organs. David Bennett Sr. was the first person to get a gene-edited pig heart, in 2022, and Richard Slayman was the first to get a kidney, in early 2024. Unfortunately, both men died around two months after their surgery.

But Towana Looney, the third living person to receive a gene-edited pig kidney, has been doing well. She had her transplant surgery in late November of last year. “I am full of energy. I got an appetite I’ve never had in eight years,” she said at the time. “I can put my hand on this kidney and feel it buzzing.” She returned home in February.

At least one company is taking more of a bodyoid-like approach. Renewal Bio, a biotech company based in Israel, hopes to grow “embryo-stage versions of people” for replacement organs.

Their approach is based on advances in the development of “synthetic embryos.” (I’m putting that term in quotation marks because, while it’s the simplest descriptor of what they are, a lot of scientists hate the term.)

Embryos start with the union of an egg cell and a sperm cell. But scientists have been working on ways to make embryos using stem cells instead. Under the right conditions, these cells can divide into structures that look a lot like a typical embryo.

Scientists don’t know how far these embryo-like structures will be able to develop. But they’re already using them to try to get cows and monkeys pregnant.

And no one really knows how to think about synthetic human embryos. Scientists don’t even really know what to call them. Rules stipulate that typical human embryos may be grown in the lab for a maximum of 14 days. Should the same rules apply to synthetic ones?

The very existence of synthetic embryos is throwing into question our understanding of what a human embryo even is. “Is it the thing that is only generated from the fusion of a sperm and an egg?” Naomi Moris, a developmental biologist at the Crick Institute in London, said to me a couple of years ago. “Is it something to do with the cell types it possesses, or the [shape] of the structure?”

The authors of the new MIT Technology Review piece also point out that such bodyoids could also help speed scientific and medical research.

At the moment, most drug research must be conducted in lab animals before clinical trials can start. But nonhuman animals may not respond the same way people do, and the vast majority of treatments that look super-promising in mice fail in humans. Such research can feel like a waste of both animal lives and time.

Scientists have been working on solutions to these problems, too. Some are creating “organs on chips”—miniature collections of cells organized on a small piece of polymer that may resemble full-size organs and can be used to test the effects of drugs.

Others are creating digital representations of human organs for the same purpose. Such digital twins can be extensively modeled, and can potentially be used to run clinical trials in silico.

Both of these approaches seem somehow more palatable to me, personally, than running experiments on a human created without the capacity to think or feel pain. The idea reminds me of the recent novel Tender Is the Flesh by Agustina Bazterrica, in which humans are bred for consumption. In the book, their vocal cords are removed so that others do not have to hear them scream.

When it comes to real-world biotechnology, though, our feelings about what is “acceptable” tend to shift. In vitro fertilization was demonized when it was first developed, for instance, with opponents arguing that it was “unnatural,” a “perilous insult,” and “the biggest threat since the atom bomb.” It is estimated that more than 12 million people have been born through IVF since Louise Brown became the first “test tube baby” 46 years ago. I wonder how we’ll all feel about bodyoids 46 years from now.

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

Autopsies can reveal intimate health details. Should they be kept private?

Over the past couple of weeks, I’ve been following news of the deaths of actor Gene Hackman and his wife, pianist Betsy Arakawa. It was heartbreaking to hear how Arakawa appeared to have died from a rare infection days before her husband, who had advanced Alzheimer’s disease and may have struggled to understand what had happened.

But as I watched the medical examiner reveal details of the couple’s health, I couldn’t help feeling a little uncomfortable. Media reports claim that the couple liked their privacy and had been out of the spotlight for decades. But here I was, on the other side of the Atlantic Ocean, being told what pills Arakawa had in her medicine cabinet, and that Hackman had undergone multiple surgeries.

It made me wonder: Should autopsy reports be kept private? A person’s cause of death is public information. But what about other intimate health details that might be revealed in a postmortem examination?

The processes and regulations surrounding autopsies vary by country, so we’ll focus on the US, where Hackman and Arakawa died. Here, a “medico-legal” autopsy may be organized by law enforcement agencies and handled through courts, while a “clinical” autopsy may be carried out at the request of family members.

And there are different levels of autopsy—some might involve examining specific organs or tissues, while more thorough examinations would involve looking at every organ and studying tissues in the lab.

The goal of an autopsy is to discover the cause of a person’s death. Autopsy reports, especially those resulting from detailed investigations, often reveal health conditions—conditions that might have been kept private while the person was alive. There are multiple federal and state laws designed to protect individuals’ health information. For example, the Health Insurance Portability and Accountability Act (HIPAA) protects “individually identifiable health information” up to 50 years after a person’s death. But some things change when a person dies.

For a start, the cause of death will end up on the death certificate. That is public information. The public nature of causes of death is taken for granted these days, says Lauren Solberg, a bioethicist at the University of Florida College of Medicine. It has become a public health statistic. She and her student Brooke Ortiz, who have been researching this topic, are more concerned about other aspects of autopsy results.

The thing is, autopsies can sometimes reveal more than what a person died from. They can also pick up what are known as incidental findings. An examiner might find that a person who died following a covid-19 infection also had another condition. Perhaps that condition was undiagnosed. Maybe it was asymptomatic. That finding wouldn’t appear on a death certificate. So who should have access to it?

The laws over who should have access to a person’s autopsy report vary by state, and even between counties within a state. Clinical autopsy results will always be made available to family members, but local laws dictate which family members have access, says Ortiz.

Genetic testing further complicates things. Sometimes the people performing autopsies will run genetic tests to help confirm the cause of death. These tests might reveal what the person died from. But they might also flag genetic factors unrelated to the cause of death that might increase the risk of other diseases.

In those cases, the person’s family members might stand to benefit from accessing that information. “My health information is my health information—until it comes to my genetic health information,” says Solberg. Genes are shared by relatives. Should they have the opportunity to learn about potential risks to their own health?

This is where things get really complicated. Ethically speaking, we should consider the wishes of the deceased. Would that person have wanted to share this information with relatives?

It’s also worth bearing in mind that a genetic risk factor is often just that; there’s often no way to know whether a person will develop a disease, or how severe the symptoms would be. And if the genetic risk is for a disease that has no treatment or cure, will telling the person’s relatives just cause them a lot of stress?

One 27-year-old experienced this when a 23&Me genetic test told her she had “a 28% chance of developing late-onset Alzheimer’s disease by age 75 and a 60% chance by age 85.”

“I’m suddenly overwhelmed by this information,” she posted on a dementia forum. “I can’t help feeling this overwhelming sense of dread and sadness that I’ll never be able to un-know this information.”

In their research, Solberg and Ortiz came across cases in which individuals who had died in motor vehicle accidents underwent autopsies that revealed other, asymptomatic conditions. One man in his 40s who died in such an accident was found to have a genetic kidney disease. A 23-year-old was found to have had kidney cancer.

Ideally, both medical teams and family members should know ahead of time what a person would have wanted—whether that’s an autopsy, genetic testing, or health privacy. Advance directives allow people to clarify their wishes for end-of-life care. But only around a third of people in the US have completed one. And they tend to focus on care before death, not after.

Solberg and Ortiz think they should be expanded. An advance directive could specify how people want to share their health information after they’ve died. “Talking about death is difficult,” says Solberg. “For physicians, for patients, for families—it can be uncomfortable.” But it is important.

On March 17, a New Mexico judge granted a request from a representative of Hackman’s estate to seal police photos and bodycam footage as well as the medical records of Hackman and Arakawa. The medical investigator is “temporarily restrained from disclosing … the Autopsy Reports and/or Death Investigation Reports for Mr. and Mrs. Hackman,” according to Deadline.

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

This annual shot might protect against HIV infections

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

Every year, my colleagues and I put together a list of what we think are the top 10 breakthrough technologies of that year. When it came to innovations in biotech, there was a clear winner: lenacapavir, a drug that was found to prevent HIV infections in 100% of the women and girls who received it in a clinical trial.

You never hear “100%” in medicine. The trial was the most successful we’ve ever seen for HIV prevention. The drug was safe, too (it’s already approved to treat HIV infections). And it only needed to be injected twice a year to offer full protection.

This week, the results of a small phase I trial for once-yearly lenacapavir injections were announced at a conference in San Francisco. These early “first in human” trials are designed to test the safety of a drug in healthy volunteers. Still, the results are incredibly promising: All the volunteers still had the drug in their blood plasma a year after their injections, and at levels that earlier studies suggest will protect them from HIV infections.

I don’t normally get too excited about phase I trials, which usually involve just a handful of volunteers and typically don’t tell us much about whether a drug is likely to work. But this trial seems to be different. Together, the lenacapavir trials could bring us a significant step closer to ending the HIV epidemic.

First, a quick recap. We’ve had effective pre-exposure prophylactic (PrEP) drugs for HIV since 2012, but these must be taken either daily or just before a person is exposed to the virus. In 2021, the US Food and Drug Administration approved the first long-acting injectable drug for HIV prevention. That drug, cabotegravir, needs to be injected every two months.

But researchers have been working on drugs that offer even longer-lasting protection. It can be difficult for people to remember to take daily pills when they’re sick, let alone when they’re healthy. And these medicines have a stigma attached to them. “People are concerned about people hearing the pills shake in their purse on the bus … or seeing them on a medicine cabinet or bedside table,” says Moupali Das, vice president of HIV prevention and virology, pediatrics, and HIV clinical development at Gilead Sciences.

Then came the lenacapavir studies. The drug is already approved as a treatment for some cases of HIV infection, but two trials last year tested its effectiveness at prevention. In one, over 5,000 women and adolescent girls in Uganda and South Africa received either twice-yearly injections of lenacapavir or a daily PrEP pill. That trial was a resounding success: There were no cases of HIV among the volunteers who got lenacapavir.

In a second trial, the drug was tested in 3,265 men and gender-diverse individuals, including transgender men, transgender women, and gender nonbinary people. The twice-yearly injections reduced the incidence of HIV in this group by 96%.

In the most recent study, which was also published in The Lancet, Das and her colleagues tested a new formulation of the drug in 40 healthy volunteers in the US. The participants still got lenacapavir, but in a slightly different formulation, and at a higher dose. And whereas the previous trials involved injections under the skin, these participants received injections into their glute muscles. Half the volunteers in this trial received a higher dose than the others.

The drug appeared to be safe. It also appears likely to be effective. These individuals weren’t at risk of HIV. But the levels of the drug in their blood plasma remained high, even in the people who got the lower dose.

A year after their injection, the levels of the drug were still higher than those seen in people who were protected from HIV in last year’s trials. This suggests the new annual shot will be just as protective as the twice-yearly shot, says Renu Singh, a senior director in clinical pharmacology at Gilead Sciences, who presented the findings at the Conference on Retroviruses and Opportunistic Infections in San Francisco.

“I was just so excited [to hear the results],” says Carina Marquez, an associate professor of medicine at the University of California, San Francisco, who both studies infectious disease and treats people with HIV.

Annual shots would make things easier—and potentially cheaper—for both patients and health-care providers, says Marquez. “It will be a game changer if it works, which looks promising from the phase I data,” she says.

The drug works by interfering with the virus’s ability to replicate. But it also seems to have some very unusual properties, says Singh. It can be taken daily or yearly. Small doses can stay in the blood for days rather than hours. And bigger doses form what’s known as a depot, which gradually releases the drug over time.

“I previously worked at the FDA, and looked at many, many different molecules and products, but I’ve never seen [anything] like this,” Singh adds. She and her colleagues have come up with nicknames for the drug, including “magical,” “the unicorn,” and “limitless len.”

Once a phase I trial is successfully completed, researchers will typically move on to a phase II trial, which is designed to test the efficacy of a drug. That’s not necessary for lenacapavir, given the unprecedented success of last year’s trials. The team at Gilead is currently planning a phase III trial, which will involve testing annual shots in large numbers of people at risk of HIV infection.

The drug isn’t approved yet, but the researchers at Gilead have submitted twice-yearly lenacapavir for approval by the FDA and the European Medicines Agency and hope to have it approved by the FDA in June, says Das. The drug is also being assessed under the EU-Medicines for all (EU-M4all) procedure, which is a collaboration between the EMA and the World Health Organizations to fast-track the approval of drugs for countries outside Europe.

With any new medicine for an infection that affects low- and middle-income countries, there are always concerns about cost. The existing formulations of lenacapvir (used for treating HIV infections) can cost around $40,000 for a year’s supply. “There’s no price for the twice-yearly [formulation] yet,” says Das.

Gilead has signed licensing agreements with six generic drug manufacturers that will sell cheaper versions of the drug in 120 low- and middle-income countries. In December, the Global Fund and other organizations announced plans to secure access to twice-yearly lenacapavir for 2 million people in such countries.

But this was an effort coordinated with the US President’s Emergency Plan for AIDS Relief (PEPFAR), a program whose very existence has come under threat following an executive order issued by the Trump administration to pause foreign aid.

“We are looking at the political situation right now and evaluating our possible options,” says Singh. “We are committed to working with the government to see what’s next and what can be done.”

The pause on US foreign aid will have devastating consequences for the health of people around the globe. And the idea that it might interfere with access to a drug that could help bring an end to the HIV epidemic—which has already claimed over 40 million lives—is a heartbreaking prospect. It is estimated that 630,000 people died from HIV-related causes in 2023. That same year, another 1.3 million people acquired HIV.

“We’re in such a good place to end the epidemic,” says Marquez. “We’ve come so far … we’ve got to go the last mile and get the product out there to the people that need it.”

Now read the rest of The Checkup

Read more from MIT Technology Review‘s archive

You can read more about why twice-yearly lenacapavir made our 2025 list of the top 10 breakthrough technologies here. (It’s also worth checking out the full list, here!)

The pharmaceutical company Merck has explored a different approach to delivering PrEP drugs—via a matchstick-size plastic tube implanted in a person’s arm. 

In 2018, Antonio Regalado broke the news that He Jiankui and his colleagues in Shenzen, China, had edited the genes of human embryos to create the first “CRISPR babies.” The team claimed to have done the procedure to ensure that the resulting children were resistant to HIV.

The first approved mRNA vaccines were for covid-19. But Moderna, the pharmaceutical company behind some of those vaccines, is now working on a similar approach for HIV.

AIDS denialism is undergoing a resurgence thanks to conspiracy-theory-promoting podcasts and books, one of which was authored by the newly appointed US secretary of health and human services, Robert F. Kennedy Jr. 

From around the web

Last week, I covered the creation of the “woolly mouse,” an animal with woolly-mammoth-like features. Its creators think they’re a step closer to bringing the mammoths back from extinction. But the woolly mammoth is just one of a list of animals scientists have been trying to “de-extinct.” The full list includes dodos, passenger pigeons, and even a frog that “gives birth” by vomiting babies out of its mouth. (Discover Wildlife)

The biotechnology company Beam Therapeutics claims to have corrected a DNA mutation in people with an incurable genetic disease that can affect the liver and lungs. It is the first time a mutated gene has been restored to normal, the team says. (New York Times)

In the peak covid-19 era of 2020, Jay Bhattacharya was considered a “fringe epidemiologist” by Francis Collins, then director of the US National Institutes of Health. Now, Collins is out and Bhattacharya may soon take his place. What happens when the “fringe” is in charge? (The Atlantic)

The Trump administration withdrew the nomination of Dave Weldon to run the Centers for Disease Control and Prevention. Weldon has a long track record of criticizing vaccines. (STAT) 

Mississippi became the third US state to ban lab-grown meat. The state’s agriculture commissioner has written that he wants his steak to come from “farm-raised beef, not a petri dish from a lab.” (Wired)

An ancient man’s remains were hacked apart and kept in a garage

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

This week I’ve been working on a story about a brain of glass. About five years ago, archaeologists found shiny black glass fragments inside the skull of a man who died in the Mount Vesuvius eruption of 79 CE. It seems they are pieces of brain, turned to glass.

Scientists have found ancient brains before—some are thought to be at least 10,000 years old. But this is the only time they’ve seen a brain turn to glass. They’ve even been able to spot neurons inside it.

The man’s remains were found at Herculaneum, an ancient city that was buried under meters of volcanic ash following the eruption. We don’t know if there are any other vitrified brains on the site. None have been found so far, but only about a quarter of the city has been excavated.

Some archaeologists want to continue excavating the site. But others argue that we need to protect it. Further digging will expose it to the elements, putting the artifacts and remains at risk of damage. You can only excavate a site once, so perhaps it’s worth waiting until we have the technology to do so in the least destructive way.

After all, there are some pretty recent horror stories of excavations involving angle grinders, and of ancient body parts ending up in garages. Future technologies might eventually make our current approaches look similarly barbaric.

The inescapable fact of fields like archaeology or paleontology is this: When you study ancient remains, you’ll probably end up damaging them in some way. Take, for example, DNA analysis. Scientists have made a huge amount of progress in this field. Today, geneticists can crack the genetic code of extinct animals and analyze DNA in soil samples to piece together the history of an environment.

But this kind of analysis essentially destroys the sample. To perform DNA analysis on human remains, scientists typically cut out a piece of bone and grind it up. They might use a tooth. But once it has been studied, that sample is gone for good.

Archaeological excavations have been performed for hundreds of years, and as recently as the 1950s, it was common for archaeologists to completely excavate a site they discovered. But those digs cause damage too.

Nowadays, when a site is discovered, archaeologists tend to focus on specific research questions they might want to answer, and excavate only enough to answer those questions, says Karl Harrison, a forensic archaeologist at the University of Exeter in the UK. “We will cross our fingers, excavate the minimal amount, and hope that the next generation of archaeologists will have new, better tools and finer abilities to work on stuff like this,” he says.

In general, scientists have also become more careful with human remains. Matteo Borrini, a forensic anthropologist at Liverpool John Moores University in the UK, curates his university’s collection of skeletal remains, which he says includes around 1,000 skeletons of medieval and Victorian Britons. The skeletons are extremely valuable for research, says Borrini, who himself has investigated the remains of one person who died from exposure to phosphorus in a match factory and another who was murdered.

When researchers ask to study the skeletons, Borrini will find out whether the research will somehow alter them. “If there is destructive sampling, we need to guarantee that the destruction will be minimal, and that there will be enough material [left] for further study,” he says. “Otherwise we don’t authorize the study.”

If only previous generations of archaeologists had taken a similar approach. Harrison told me the story of the discovery of “St Bees man,” a medieval man found in a lead coffin in Cumbria, UK, in 1981. The man, thought to have died in the 1300s, was found to be extraordinarily well preserved—his skin was intact, his organs were present, and he even still had his body hair.

Normally, archaeologists would dig up such ancient specimens with care, using tools made of natural substances like stone or brick, says Harrison. Not so for St Bees man. “His coffin was opened with an angle grinder,” says Harrison. The man’s body was removed and “stuck in a truck,” where he underwent a standard modern forensic postmortem, he adds.

“His thorax would have been opened up, his organs [removed and] weighed, [and] the top of his head would have been cut off,” says Harrison. Samples of the man’s organs “were kept in [the pathologist’s] garage for 40 years.”

If St Bees man were discovered today, the story would be completely different. The coffin itself would be recognized as a precious ancient artifact that should be handled with care, and the man’s remains would be scanned and imaged in the least destructive way possible, says Harrison.

Even Lindow man, who was discovered a mere three years later in nearby Manchester, got better treatment. His remains were found in a peat bog, and he is thought to have died over 2,000 years ago. Unlike poor St Bees man, he underwent careful scientific investigation, and his remains took pride of place in the British Museum. Harrison remembers going to see the exhibit when he was 10 years old. 

Harrison says he’s dreaming of minimally destructive DNA technologies—tools that might help us understand the lives of long-dead people without damaging their remains. I’m looking forward to covering those in the future. (In the meantime, I’m personally dreaming of a trip to—respectfully and carefully—visit Herculaneum.)

Now read the rest of The Checkup

Read more from MIT Technology Review‘s archive

Some believe an “ancient-DNA revolution” is underway, as scientists use modern technologies to learn about human, animal, and environmental remains from the past. My colleague Antonio Regalado has the details in his recent feature. The piece was published in the latest edition of our magazine, which focuses on relationships.

Ancient DNA analysis made it to MIT Technology Review’s annual list of top 10 Breakthrough Technologies in 2023. You can read our thoughts on the breakthroughs of 2025 here. 

DNA that was frozen for 2 million years was sequenced in 2022. The ancient DNA fragments, which were recovered from Greenland, may offer insight into the environment of the polar desert at the time.

Environmental DNA, also known as eDNA, can help scientists assemble a snapshot of all the organisms in a given place. Some are studying samples collected from Angkor Wat in Cambodia, which is believed to have been built in the 12th century.

Others are hoping that ancient DNA can be used to “de-extinct” animals that once lived on Earth. Colossal Biosciences is hoping to resurrect the dodo and the woolly mammoth.

From around the web

Next-generation obesity drugs might be too effective. One trial participant lost 22% of her body weight in nine months. Another lost 30% of his weight in just eight months. (STAT)

A US court upheld the conviction of Elizabeth Holmes, the disgraced founder of the biotechnology company Theranos, who was sentenced to over 11 years for defrauding investors out of hundreds of millions of dollars. Her sentence has since been reduced by two years for good behavior. (The Guardian)

An unvaccinated child died of measles in Texas. The death is the first reported as a result of the outbreak that is spreading in Texas and New Mexico, and the first measles death reported in the US in a decade. Health and Human Services Secretary Robert F. Kennedy Jr. appears to be downplaying the outbreak. (NBC News)

A mysterious disease with Ebola-like symptoms has emerged in the Democratic Republic of Congo. Hundreds of people have been infected in the last five weeks, and more than 50 people have died. (Wired)

Towana Looney has been discharged from the hospital three months after receiving a gene-edited pig kidney. “I’m so grateful to be alive and thankful to have received this incredible gift,” she said. (NYU Langone)