Cannabis: Now you can measure how much is too much

Alexander Freund

DW

January 12, 2026

At what point does smoking weed get dangerous? A British study measured cannabis consumption in THC units and determined which amounts increase health risks. The system comes with clear risk thresholds ― and weaknesses.

THC units can make the conversation around cannabis consumption more precise

Image: Henry Romero/REUTERS


Even just a few joints a week can make a difference ― measured in milligrams of THC. A new study by researcher Rachel L. Thorne and her team provides the first concrete thresholds for the weekly dose at which the risk of cannabis use disorder increases significantly. Thorne is a research associate in the psychology department at the University of Bath, UK, whose areas of expertise include cannabis use and its consequences for youth and adult health. The study was published on Monday in the journal Addiction.
How much THC per week poses a health risk?

The researchers used data from the CannTeen study involving 85 adolescents (aged 16 to 17) and 65 adults (aged 26 to 29) who had used cannabis in the past year. One THC unit, defined as 5 milligrams, is analogous to the standard unit used to compare beer, wine and spirits in alcohol research.

Based on surveys of consumption patterns and a clinical diagnosis at the end of the study, the researchers derived thresholds that mark the difference between unremarkable consumption and cannabis use disorder.

A cannabis use disorder is present when someone can no longer control their cannabis consumption and continues to use despite clear problems in everyday life. Typical signs of the disorder are neglecting responsibilities at school, work or with family, and withdrawal symptoms such as restlessness or sleeping issues when trying to quit.

For adolescents, this threshold was around 6 THC units per week ― i.e., around 30 milligrams of THC ― and for adults, it was around 8 units, or around 40 milligrams per week. For moderate to severe disorders, the values were higher. The research team emphasized that only abstinence is completely risk-free.

THC units based on alcohol research

In alcohol research, consumption is also generally measured in standard drinks or units, and thresholds for "risky" behavior, like binge drinking, have been established.

"Threshold values are generally very useful for communicating health risks," says Jakob Manthey from the Centre for Interdisciplinary Addiction Research at the University of Hamburg.

But there is also a risk that such values can be misinterpreted.

"There is a danger that consumption below the threshold value will be interpreted as harmless or even beneficial to health," says Manthey, who was not involved in the study.

Unlike alcohol, however, cannabis contains many active ingredients whose interaction influences the drug's effects and risks. Although THC is indeed the most important risk factor, other cannabinoids produced by the plant, as well as the form of consumption ― whether via a joint, vaporizer or edible ― can significantly alter both dose and effect.

How reliable are the THC figures in the study?

One of the study’s strengths is that the researchers repeatedly asked the same individuals about their cannabis use over the course of an entire year. However, the sample size is small (150 individuals), and the actual THC content of the products consumed had to be estimated from external sources, as no lab analyses of individual samples was performed.

The figures the study quotes should therefore be understood as initial guidelines rather than hard limits. But they show, unsurprisingly, that the higher the weekly THC intake, the greater the risk of cannabis use disorder becomes.

A younger brain with cannabis?  02:19

Benefits for diagnosis, therapy and prevention in cannabis use

The new thresholds do not replace doctors or therapists for diagnosis and treatment, but they can help with preliminary screening. Specialists could, for instance, begin asking those affected how many THC units they consume per week in order to better assess risk and detect a potential disorder at an earlier stage.

In doing so, they would be following guidelines for the treatment of cannabis-related disorders, which state that frequency and quantity of consumption ― as well as the potency of cannabis consumed ― are important risk factors.

A standardized unit system could help make this information more comparable in the future. It will not, however, change consumption patterns all on its own, since availability, advertising and measures such as youth protection and advertising restrictions play a major role in that as well.

What THC units can do ― and what they can't

Practical applicability remains a key problem: Many consumers simply don’t know how much THC their products contain, especially if they are home-grown or sourced illegally.
"Under the current regulations, there will be no widespread communication of THC units, so consumers often have no reliable way of knowing the THC content of the products available," says Jakob Manthey.

British neuropsychopharmacologist David Nutt still views the new analysis as an important step.

"The data provide an estimate of a threshold of weekly consumption to eliminate dependence risk," Nutt said.

He is calling for "a regulated cannabis market with clear product quality and identification of unit amounts (as required for alcohol currently)."

The proposed THC units would clarify previously vague terms like "a lot" or "risky" when it comes to cannabis consumption. But those wanting to protect their health need more than just a weekly unit number. They also need honest information about potency, effective prevention and, when in doubt, the willingness to limit consumption or quit altogether.

This article was translated from German



Alexander Freund Science editor with a focus on archaeology, history and health

 

Early alcohol exposure is common among Chinese teenagers

Zhejiang University

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

National patterns of alcohol use among Chinese adolescents. This graphical summary illustrates findings from a nationally representative, school-based survey of Chinese adolescents aged 12–19 years conducted in 2021. The data show that alcohol consumption is widespread, with 44.1% reporting lifetime use and nearly one-third initiating drinking at age 13 or younger. While drunkenness is less common than alcohol use, clear patterns emerge by beverage type, drinking frequency, emotional motives, and social context. Drinking most often occurs infrequently, during family gatherings, and in private homes, highlighting the strong influence of social and cultural environments on adolescent alcohol exposure.

view more 

Credit: World Journal of Pediatrics

Alcohol consumption during adolescence poses long-term risks to physical health, brain development, and social well-being. A large national survey provides updated evidence on how common drinking remains among Chinese adolescents and how it varies by age, gender, and region. The study reveals a substantial proportion of middle and high school students have tried alcohol, with many initiating drinking at an early age. While severe intoxication is less frequent than alcohol use itself, notable disparities persist across sex, residence, and geographic regions. These findings highlight that underage drinking remains a widespread public health issue and underscore the need for targeted prevention strategies addressing early exposure, social contexts of drinking, and vulnerable subgroups. 

Alcohol use during adolescence occurs at a critical stage of neurological and psychological development and is associated with injuries, risk behaviors, impaired learning, and long-term health outcomes. Although alcohol consumption among Chinese adults has shown mixed trends over recent decades, nationally representative data on adolescent drinking have been limited. Previous surveys were either outdated or restricted to specific regions, leaving uncertainty about current patterns at the national level. Understanding the alcohol consumption patterns among Chinese adolescents is essential for policies designing. Therefore, an in-depth, national-wide investigation was conducted, aiming to solve this crucial issue.

Researchers from the Chinese Center for Disease Control and Prevention and collaborating institutions reported new findings (DOI: 10.1007/s12519-025-00994-4) in World Journal of Pediatrics in December 2025, presenting results from a nationally representative school-based survey conducted in 2021. The study examined alcohol use among adolescents aged 12 to 19 years across mainland China. By analyzing drinking prevalence, age of initiation, beverage types, emotional motives, and drinking locations, the research offers the most comprehensive and up-to-date national patterns of adolescent alcohol consumption in China.

The survey shows that an estimated 44.1% of students reported having consumed alcohol at least once in their lifetime, while 32.7% drank in the past year and 11.2% in the past month. Although drunkenness was less frequent—affecting 12.1% over a lifetime and only 1.6% in the past month—it remains a significant concern, especially among specific subgroups. Boys consistently reported higher levels of drinking and intoxication than girls across all time frames.

Early exposure emerged as a key issue. Nearly one-third of students reported initiating alcohol use at age 13 or younger, and almost 7% experienced drunkenness at an early age. Drinking prevalence increased steadily with school grade, indicating cumulative exposure as adolescents grow older. Geographic disparities were also evident, with higher levels of drinking and drunkenness in rural areas and certain regions, particularly Central and Southwest China.

Beer and wine were the most commonly consumed beverages, while spirits were less frequent. Importantly, adolescent drinking often occurred in family settings and private homes, frequently without strong emotional motives. This pattern suggests that alcohol use is embedded in social and cultural contexts rather than driven solely by deliberate risk-taking.

"This national survey provides a clear reminder that underage drinking remains a widespread and socially embedded behavior," the researchers noted. They emphasized that although severe intoxication has declined compared with earlier surveys, early initiation and persistent exposure continue to pose long-term risks. The findings highlight the importance of parental influence, family environments, and social norms in shaping adolescent drinking behaviors. According to the authors, prevention efforts should move beyond individual education and address broader cultural and environmental factors that normalize alcohol use among young people.

The results offer valuable evidence for public health policy and prevention programs targeting underage drinking in China. By identifying early initiation, family-centered drinking occasions, and regional disparities, the study points to concrete opportunities for intervention. Strengthening parental guidance, improving enforcement of age restrictions, and tailoring strategies to high-risk regions and rural communities could reduce early alcohol exposure. More broadly, the findings support the need for sustained national monitoring and culturally sensitive prevention efforts. Addressing adolescent alcohol use early may help curb future health burdens and reduce the long-term impact of alcohol-related harm across the population.

###

References

DOI

10.1007/s12519-025-00994-4

Original Source URL

https://doi.org/10.1007/s12519-025-00994-4

Funding information

Fujian Research and Training Grants for Young and Middle—Aged Leaders in Healthcare.

About World Journal of Pediatrics

World Journal of Pediatrics is a monthly, peer-reviewed academic journal that publishes original research articles, reviews, and special reports covering all aspects of pediatrics. It welcomes contributions from pediatricians and researchers worldwide, focusing on the latest developments in pediatric clinical practice, pediatric surgery, preventive child healthcare, pharmacology, stomatology, and biomedicine, as well as basic and experimental sciences. The journal provides an international platform for academic exchange and dissemination of medical research findings. All submissions undergo rigorous peer review by at least two experts. Committed to efficient manuscript processing, the journal aims to deliver final decisions within two months, with outstanding papers or special reports potentially accepted within one month for priority publication.

---

Journal

World Journal of Pediatrics

DOI

10.1007/s12519-025-00994-4 

Subject of Research

Not applicable

Article Title

Alcohol consumption is prevalent among Chinese adolescents: a national survey

 

What if ADHD risk isn’t fixed at birth, but shaped by how early environments interact with a child’s sensitivity?

Ben-Gurion University of the Negev

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Simple slopes and Johnson–Neyman plot for the interaction between infant surgency and early home environment. Panel A presents the simple slopes pattern of the interaction between neonatal surgency and the home environment. Panel B shows the Johnson–Neyman region of significance analysis for the slope of the early home environment, as a function of neonatal surgency levels; significant regions (in blue, p < 0.05) indicate that the early home environment significantly predicts child EF (executive function) for infants with these levels of neonatal surgency. Panel C shows the Johnson–Neyman region of significance analysis for the slope of neonatal surgency, as a function of early home environment levels; significant regions (in blue, p < 0.05) indicate that neonatal surgency significantly predicts child EF at specific levels of the early home environment.

view more 

Credit: Prof. Andrea Berger/BGU

BEER-SHEVA, Israel, January 8, 2026 – A 17-year longitudinal study from Ben-Gurion University of the Negev followed children from birth to adolescence to explore whether early-life factors can predict ADHD, and for whom the environment matters most.

Published in Infant and Child Development (https://doi.org/10.1002/icd.70072), the study tracked ~125 children and their parents, examining infant temperament, parental ADHD symptoms, and the richness of the early home environment.

The key finding: Early “risk factors” don’t affect all children equally.

Led by Profs. Andrea Berger and Judith G. Auerbach (BGU), together with Dr. Tzlil Einziger, the researchers found that infants showing high motor activity, especially those with parents who have elevated ADHD symptoms — were more sensitive to their environment.

For these children, a rich and supportive home environment strongly predicted better cognitive functioning by age 7, which in turn was linked to fewer ADHD symptoms in later childhood and adolescence. The same sensitivity meant they benefited most from supportive environments — and were more negatively affected by less enriching ones.

"There aren’t just “sensitive” and “non-sensitive” children," explains Prof. Berger, "Sensitivity exists on a continuum, shaped by the interaction between child temperament and parental characteristics."

"Understanding this can help tailor early environments to better support children who need it most," concludes Prof. Auerbach.

Additional researchers included: Prof. Naama Atzaba-Poria, Drs. Rivka Landau, Shoshana Arbelle and Michael Karplus.

The study was supported by the Israel Science Foundation (ISF) (Grant Nos. 756/98-01, 869-01, 1058/16).

---

Journal

Infant and Child Development

DOI

10.1002/icd.70072 

Method of Research

Observational study

Subject of Research

People

Article Title

Neonatal Surgency Moderates the Association Between the Home Environment and Executive Functions in Children With a Family History of ADHD

Why Greenland's melting ice cap threatens humanity, and could serve Trump

As the White House looks to take control of Greenland, US President Donald Trump is eyeing not just a strategic foothold in the Arctic but the territory's vast underground resources. While the melting of the island's glaciers could make land and minerals easier to exploit, it could also wipe hundreds of thousands of cities off the map.

Issued on: 08/01/2026 - RFI

An iceberg melting in Scoresby Fjord, eastern Greenland.

 © AFP - OLIVIER MORIN

Greenland is vast, and highly coveted. Covering some 2 million square kilometres, it is almost four times the size of France.

Above all, it is the second-largest body of ice on Earth after Antarctica, at the opposite pole.

The ice mass is beginning to melt and could ultimately trigger a dramatic rise in sea levels. Unlike sea ice, which floats, Greenland’s ice sheet lies on land. And that makes all the difference.

"In Greenland, we are dealing with extremely large masses, enormous volumes, covering the entire island," says Glenn Yannic, a lecturer and researcher at Savoie Mont Blanc University. "We're talking about an ice sheet that can be several hundred metres thick. It is estimated that the complete melting of Greenland could raise sea levels by five, six or seven metres."

The melting of the ice sheet – rather than the summer thaw of Arctic sea ice – is what causes sea levels to rise, the Greenland specialist explains. "When sea ice melts, it's like putting an ice cube into a glass filled to the brim: the ice cube melts, but the water level does not rise," he tells RFI.

Greenland melted recently, says study that raises future sea level threat

Accelerating warming

According to Copernicus – the Earth observation component of the European Union's Space programme – for every centimetre of sea level rise, around 6 million more people are exposed to coastal flooding.

A rise in sea levels of five to seven metres by the end of the century would lead to the disappearance of thousands of coastal cities worldwide, affecting millions of people.

Such a scenario is becoming increasingly plausible, because Greenland is one of the fastest-warming regions on the planet. Last spring, glaciers melted 17 times faster than average amid record temperatures.

Icebergs float in a fjord after calving off from glaciers on the Greenland ice sheet in south-eastern Greenland, August 2017. © AP - David Goldman

New research, published by US scientists on 5 January in Nature Geoscience, has also alarmed the scientific community. Using ice core samples, researchers found that Greenland's ice dome last melted around 7,000 years ago, during the early Holocene period, when "temperatures were three to five degrees C higher than those currently observed", Yannic says.

"They showed that part of northern Greenland was ice-free. That's the whole significance of this study, and why it's had such an impact. Three to five degrees C – we are almost there, we are on the brink. By the end of the century, we can predict that all the ice currently covering Greenland will have melted."

Arctic sees unprecedented heat as climate impacts cascade

In Trump’s sights

A wealth of natural resources lies beneath Greenland’s ice, including rare earth elements and suspected fossil fuel reserves.

Trump has made no secret of his desire to exploit them.

And since the US ousting of Venezuela’s president Nicolás Maduro, partly to secure Venezuelan oil, Trump has renewed calls for a US takeover of the Arctic territory.

On Sunday, he said that he needed Greenland "very badly" for reasons of "national security", given its strategic position between the US and Russia. But Trump is also eyeing resources such as hydrocarbons, minerals and even water – so pure it is said to be worth its weight in gold.

Access to Greenland's ice-capped resources has remained a challenge, but "the acceleration in the melting of the ice sheet will free up areas and make it easier to access certain mineral deposits", says Yannic.

If Trump were to succeed, the man who called climate change a "con job" could could end up benefitting from global warming.

“The issue of the search for minerals and hydrocarbons, and their exploitation, has already been put before the Greenland government, which decided several years ago to impose a moratorium on such activities,” Yannic says.

Prospecting was halted in order to protect the environment. For the moment, Greenland is holding firm – but for how long?

This article, adapted from the original in French by RFI's Florent Guinard, has been lightly edited for clarity.

Trump's grotesque Greenland fantasy ignores very real crisis bubbling under the surface

Bill Mckibben,

 Common Dreams
January 8, 2026 


Donald Trump speaks at Mar-a-Lago, with Marco Rubio and Pete Hegseth. REUTERS/Jonathan Ernst

When President Donald Trump first started fantasizing about seizing Greenland for the US, it sounded farcical — a little Gilbert and Sullivan, or maybe The Mouse that Roared. In the wake of America’s attack on Caracas, however, it now seems as likely as not that we’ll soon be landing troops in Nuuk, a truly hideous prospect that we should all try to head off. Here’s my small effort:

First off, I think it’s a very real possibility. Here’s Stephen Miller on Monday, talking with Jake Tapper:
TAPPER: Can you rule out the US is going to take Greenland by force?

MILLER: Greenland should be part of the US. By what right does Denmark assert control over Greenland? The US is the power of NATO.

TAPPER: So force is on the table?

MILLER: Nobody is gonna fight the US militarily over future of Greenland.

And here’s our leader himself, speaking to a press gaggle on Air Force One while a beaming Sen. Lindsay Graham (R-Obsequious) grinned by his side:

TRUMP: We need Greenland. Right now, Greenland is covered with Russian and Chinese ships.

REPORTER: What would the justification be for a claim to Greenland?

TRUMP: The EU needs us to have it.

None of this makes any actual sense — Greenland is not covered with Chinese and Russian ships, the EU does not want us to have it (European leaders united Tuesday to say, “Greenland belongs to its people. It is for Denmark and Greenland, and them only, to decide on matters concerning Denmark and Greenland,” which seems pretty clear), and Denmark asserts control over Greenland in pretty much the same way Washington asserts control over, say, Alaska or Vermont.

In fact, though, Denmark has been slowly loosening that control over the decades — not because it wants to sell it to America, but because it recognizes that the people who live there, most of whom are Inuit, should have the greatest say in how it’s managed. Greenlanders have exercised that say in ways that would be uncongenial to the White House: for instance, civil partnerships for gay people have been standard since 1996, and gay marriage legal since 2016 when the island’s parliament approved it by a 28-0 vote. Under the Kinguaassiorsinnaajunnaarsagaaneq pillugu inatsit law, sex changes have been allowed since 1976.

In other words, Trump’s claim that Greenlanders “want to be with us” is palpable nonsense — a poll last January found that 85 percent of the population opposed the idea.

Discerning Trump’s “real” reason for wanting Greenland is a pointless exercise; he’s a sad, ancient baby, and babies just want.

He seems to think that the point of a ruler is to acquire more territory, and that he more or less owns by divine right the land masses adjacent to our country. (MAGA bloggers this week were busily talking about “vassal states” across the hemisphere). There are minerals there, but hard to get at. Oh, and there’s petroleum in and around Greenland as well, and that usually sings a siren song to this child of the oil-driven 20th century.

Really, however, there’s only one truly vital strategic asset in Greenland, one thing that could change the world. And that’s the ice that covers almost all its landmass.

I’ve been up on this ice sheet — I’ve hiked up glaciers from the tideline, climbing and climbing till the sea disappears behind you and all you can see in every direction is white. It is uncannily beautiful.

I helped organize a trip there in 2018 so that two very fine poets could record a piece from atop this ice sheet. Kathy Jetnil-Kijiner came from her home in the Marshall Islands, which is already slipping under a rising sea (and which has long known about US imperialism; part of the atoll is still radioactive and off limits, thanks to US bomb testing in the 1950s); Aka Niviana is a native Greenlander whose home has begun to melt, a melt that if it continues will guarantee the submersion of Polynesia, and much else.

They stood there on that ice, in a chill summer wind, and recited their long and majestic poem for a camera; my job was to stand just outside its range with a pair of sleeping bags that they could wrap themselves in between takes. “Rise: From One Island to Another,” as their work was called, has won both prizes and large audiences on YouTube; it will, I think, be one of the documents of this global warming era that someday people will look at in a kind of outraged awe, one more proof that we knew exactly what was coming and did nothing about it.

We were camped above the Eagle Glacier — Jason Box, the American-born climatologist now living in Denmark who helped lead the trip, had named it that because of its shape when he first visited five years earlier, “but now the head and the wings of the bird have melted away. I don’t know what we should call it now, but the eagle is dead.” And that’s true of so much of the island; we watched as one iceberg after another came crashing off the head of glaciers, each one raising the level of the ocean by some infinitesimal amount.

Greenland holds 23 feet of sea-level rise, should we eventually melt it all. That will take a while, but we’re doing our best. It’s been losing mass steadily for the last quarter-century — it lost 105 billion tons of ice (billion with a b) in 2025, and the ice was melting well into September, unusual in a place where winter usually descends in late August. The people of Greenland, by the way, recognize all this: They passed a law in 2021 banning all new oil exploration and drilling — the government described it as “a natural step” because Greenland “takes the climate crisis seriously.” (More than two-thirds of their power comes from renewables, mostly hydro).

I found those Greenlanders I met to be hardy, thrifty people very much in tune with their place. I spent a memorable afternoon with Box planting trees outside the former American air base in Narsarsuaq in an effort to, among other things, soak up some carbon dioxide. And I spent an equally pleasant afternoon drinking beer with him and the rest of our party at a microbrewery in Saqqannguaq (one of several in the country) which brews “with the purest drinking water on Earth, coming from the Greenlandic ice cap” and hence “free of toxins, chemicals, and microplastics.” Highly recommend the IPA, reminder of yet another imperial adventure.

Obviously seizing Greenland would be a terrible idea because it would break up NATO and put America at loggerheads with the liberal democracies of Europe (though that may be the single biggest incentive for the administration). Obviously, it would be a gross example of modern colonization, obliterating the rights of the people who live there. Obviously, it would raise tensions around the world even higher, and send the strongest possible signal that Beijing should just go grab Taiwan. Lots of people are talking about those things, though there’s not the slightest sign that anyone in power is listening. (Miller’s wife has tweeted out a map of Greenland decked out in red and white stripes).

But in a rational world what we’d mostly be talking about is all that ice. That’s what, for the other 8 billion people on the planet, actually matters about this island. It could easily add a foot or more to the level of the ocean before the century is out, all by itself (the Antarctic, much bigger but slower to melt, will eventually add much more). A foot is a lot — on a typical beach on, say, the Jersey shore, which slopes up at about 1°, that brings the ocean about 90 feet inland.

And the fresh water pouring off Greenland seems already to be disrupting the great conveyor belt currents that bring warm water north from the equator, maintaining the climates of the surrounding continents. That too could raise—by significant amounts—the level of the sea, especially along the coast of the southeast US (and also plunge Europe into the deep freeze even as the rest of the planet warms).


The stakes are so enormous that they make the Trumpian greed for this land seem all the punier and more puerile. Here’s how Jetnil-Kijiner and Niviana put it in their poem:

We demand that the world see beyond
SUVs, ACs, their pre-package convenience
Their oil-slicked dreams, beyond the belief
That tomorrow will never happen

And yet there’s a generosity to their witness — a recognition that whoever started the trouble, we’re now in it together.

Let me bring my home to yours
Let’s watch as Miami, New York,
Shanghai, Amsterdam, London
Rio de Janeiro and Osaka
Try to breathe underwater…
None of us is immune.
Life in all forms demands
The same respect we all give to money…
So each and every one of us
Has to decide
If we
Will
Rise

DRINKING BEER IN A PUB, SMOKING FAGS & THROWING DARTS 

Littler signs reported record £20 million darts deal

London (AFP) – World champion Luke Littler has agreed the most lucrative sponsorship deal in darts' history, worth a reported £20 million ($27 million).

Issued on: 09/01/2026 - RFI

Luke Littler is a two-time world darts champion © Ben STANSALL / AFP

The 18-year-old Englishman, who earned the sport's first £1 million prize pot after winning a second successive World Championship title at London's Alexandra Palace last weekend, has renewed his contract with manufacturer Target Darts.

According to Britain's Press Association, the new deal -- including potential earnings and bonuses, as well as a percentage of sales of products and equipment -- is worth £20 million over 10 years.

Littler became a break-out star with his debut run to the 2024 World Championship final as a 16-year-old, when he lost to compatriot Luke Humphries, with the teenager's branded darts and magnetic board proving a sales success throughout Britain.

"Target has believed in me from day one and I'm delighted that there are many more years to come," Littler, who is also managed by the company, said in a statement.

"From my playing career to my product range, we've built everything together and I'm really excited to commit to our partnership long-term and see where we can take this next."

Target chairman Garry Plummer added: "I met Luke at the BDO Youth World Championship Qualifier when he was 12, and that day his dad asked if we would sponsor him.

"We'd never taken on someone so young, but I saw something special in him and saying yes was easy.

"Watching him grow since, as both a player and a person, has been a privilege. His achievements on and off the oche have been remarkable, and this new agreement celebrates everything we've built together and the exciting future ahead."

World number one Littler is preparing for the World Series double-header in Bahrain and Saudi Arabia.

© 2026 AFP

 

From pint to plate: scientists brew up a new way to grow meat

University College London

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

Yeast left over from brewing beer can be transformed into edible ‘scaffolds’ for cultivated meat – sometimes known as lab-grown meat – which could offer a more sustainable, cost-effective alternative to current methods, according to a new study from UCL (University College London) researchers.

‘Nose to tail’ eating, which emphasises the use of the whole animal, has long been an ethos of sustainability-conscious chefs and diners. But as cultivated meat comes closer to supermarket shelves, a new innovation could see a ‘pint to plate’ approach to serving up burgers and steaks.

The new study, published in Frontiers in Nutrition, explores how bacterial cellulose grown from yeast left over from brewing beer can be used to grow cultivated meat, an emerging form of food production that grows animal cells on an edible scaffold in the lab.

In nature, cellulose is a hardy substance that gives structure to plant cells. Similarly, bacterial cellulose is created by microbes to create a protective layer around the organism’s cells.

Historically, bacterial cellulose has been used to make nata de coco, a jelly-like dessert from the Philippines. But in recent years, improvements in cultivating both plant and bacterial cellulose have seen their useful properties applied to everything from plant-based foods to 3D-printed bandages.

Now researchers believe that bacterial cellulose may be able to help solve the challenge of creating affordable, edible scaffolds that replicate the texture and structure of animal tissue to grow animal cells on, which has hampered the cultivated meat industry’s ability to scale up and bring products to market.

One untapped source of bacterial cellulose is brewer’s spent yeast, a by-product of beer fermentation that often ends up being thrown away.

Professor Richard Day, senior author of the study from UCL Division of Medicine, said: “Cultivated meat has the potential to revolutionise food production, but its success depends on overcoming key technical challenges.

“While it’s relatively easy to grow animal cells for mass food production you need to be able to grow them on something cheap, edible and that preferably provides a structure that resembles real meat.

“Our research shows that brewing waste, which is often discarded, can be repurposed to grow bacterial cellulose with properties suitable for meat scaffolding. This could significantly reduce costs and environmental impact.”

For the proof-of-concept study, researchers from UCL collected spent yeast from the Big Smoke Brewing Company in Esher, Surrey, and used it to culture Komagataeibacter xylinus, a bacterium known for producing high-quality cellulose.

The resulting cellulose was tested using a ‘chewing machine’ – a probe that repeatedly compresses a substance while measuring forces like chewiness, hardness and stickiness – to assess its structural and mechanical properties.

The team found that when used in place of a conventional nutrient broth used for growing the bacteria, the beer waste produced bacterial cellulose of equal quality, which was actually closer in texture to natural meat products, with lower hardness and chewiness than ‘standard’ cellulose.

Most importantly, when animal cells (fibroblasts, a cell type found in meat) were placed on the beer waste-derived scaffold they attached to it, indicating that the material can support cell growth for cultivated meat production – though the researchers stress that the project is at an early stage and further work is needed.

The team plan to further develop the approach by incorporating other cell types found in natural meat, such as fat and muscle cells. They also plan to test spent yeast from different types of beer to assess bacterial cellulose yields and the quality of the resulting scaffolds.

Christian Harrison, the study’s first author and a PhD student from UCL Division of Medicine, said: “One of the biggest hurdles in cultivated meat is replicating the ‘mouthfeel’ and texture of real meat. Our findings suggest that bacterial cellulose grown on brewing waste not only supports cell growth but also mimics the mechanical properties of meat more closely than other scaffolds.

“This opens up exciting possibilities for scalable, sustainable meat alternatives. In this study we collected a relatively small amount of raw material from one craft brewery, that would otherwise have gone to waste. But huge volumes of brewing waste are generated each year that could have a valuable use.”

This research was supported by the Biotechnology and Biological Sciences Research Council (BBSRC).

---

Journal

Frontiers in Nutrition

DOI

10.3389/fnut.2025.1656960