Hilary Duff reflected on her child star upbringing at the TIME100 Summit in Manhattan, where Time executive editor Dan Macsai asked if documentaries like “Quiet on Set: The Dark Side of Kids TV” or “Framing Britney Spears” changed her perspective on being a child star in the early 2000s.
“I think I feel really quite sad when I watch a lot of those documentaries, for obvious reasons,” Duff said. “I feel very grateful that I wasn’t put in too many positions that left battle wounds on me. But I have held a job as an adult since I was nine years old. I have a very different upbringing. I have a lot of missed experiences, but also a lot of amazing [ones].”
In recent years, a wave of documentaries and longform reporting has exposed the harmful conditions many child stars faced at the turn of the 21st century. The 2024 docuseries “Quiet on Set: The Dark Side of Kids TV” detailed allegations of abuse, sexism, racism and inappropriate dynamics involving children and teen stars tied to former Nickelodeon showrunner Dan Schneider, who later sued the producers for defamation, calling the series a “hit job.” A few years prior, FX’s 2021 documentary “Framing Britney Spears” helped legitimize the #FreeBritney movement by detailing the pop star’s struggles growing up in the spotlight.
For Duff, she says the less-rosy side of her Disney Channel years came from the pressures of early responsibility.
“I’m a scrubby kid from Texas,” Duff explained. “Sometimes I’m like, ‘How did I end up here?’ I think it goes to the luck of something, but it doesn’t take away the fact that I’ve worked as an adult since such a young age — and had to be able to hold my own in a room full of adults constantly. I was expected to show up and be professional through exhaustion or sickness or whatever. It’s taught me a lot, and it’s completely formed who I am. And I’m proud of that person.”
Duff, best known for “Lizzie McGuire,” said she’s “finally taking some ownership” of her life with “Luck… or Something,” her first album in over a decade. Calling the work her “boldest and most self-assured,” the former Disney star seems grateful to be settled in a more adult era of her journey.
“Coming up as a child actor, it’s hard to get out of that,” Duff said. ”I’m at 38, and I feel like now I’m finally able to take agency in my life and make decisions that I’m really confident in. Although I did before, but there’s just a level now where I’m like, ‘I’m the adult in the room. Finally!’”
Up next for Duff is “The Lucky Me Tour,” which kicks off in June and runs through February 2027.
Share on PinterestThe time it takes for stool to transit through your body can affect your health. Image Credit: AUDSHULE/Stocksy
Research suggests that the amount of time stool spends in your body may affect your overall health.
This may be due to changes in gut microbiomes associated with how quickly or slowly stool moves through the body.
An expert explains long-term health issues associated with slow digestion, chronic constipation, and chronic diarrhea.
The amount of time it takes for stool to move through your body may impact your health in more ways than you may think.
A 2023 study showed that there may be distinct differences in gut microbiomes depending on whether your stool is fast or slow.
This study also looked at previous research on gut transit time. All of the research had the same goal of estimating how long food stays in a person’s colon.
The longer it stays, the more time bacteria have to ferment the contents, regulate acidity in the gut, and produce metabolites that can influence the body’s health.
The study found that people with faster gut transit times had drastically different microbiomes than those with slower transit times.
One approach to estimating the gut transit time was the Bristol Stool Scale. This is a visual tool that classifies stool by consistency. For example, hard, rock-like pellets typically mean a long transit time. Watery, mushy stool often indicates a short transit time.
Transit time can also influence how your body responds to probiotics, as well as supplements and medications that interact with the gut.
“The gut is far more than a digestive organ — it is a finely tuned ecosystem whose balance underpins everything from immune function and metabolic health to neurological well-being and cancer risk,” said Ketan Thanki, MD, board certified colorectal surgeon who specializes in benign and malignant disease of the colon, rectum, and anus with the MemorialCare Todd Cancer Institute at Long Beach Medical Center in Long Beach, CA.
Healthline spoke with Thanki to learn more about how poop transit time can impact health.
This interview has been lightly edited for length and clarity.
Thanki: Gut transit time is a major determinant of microbiome composition, diversity, and metabolism.
Slower colonic transit time is consistently associated with a shift away from beneficial sugar fermentation, which produces health-promoting short-chain fatty acids (SCFAs) and toward protein fermentation that generates potentially harmful byproducts like ammonia and phenols.
The relationship works both ways: transit time shapes which microbial communities thrive, but microbiota and their metabolites — including SCFAs and secondary bile acids — directly influence gut motility.
Thanki: When transit slows, fermentable carbohydrates become depleted before stool reaches the distal colon, and bacteria switch from fermenting carbohydrates into healthful short-chain fatty acids to fermenting proteins instead (proteolysis).
This produces metabolites — ammonia, hydrogen sulfide, phenols, indoles, and branched-chain fatty acids — that are directly toxic to colonocytes, damage colonocyte DNA, cause cancer-causing mutations, and promote a leaky gut lining, thereby promoting systemic inflammation.
Meanwhile, increased methane production further slows the gut, and increased estrogens in the blood can increase the risk of malignancies like breast cancer and dysregulate levels of other hormones.
SCFA depletion affects systemic metabolism. SCFAs are not just local (colonocyte) fuel. They also signal to the liver to regulate glucose production, and influence adipose tissue metabolism, insulin sensitivity, and secretion of appetite hormones (GLP-1, PYY).
When prolonged transit time reduces SCFA production, these regulatory signals are diminished. This is particularly relevant in diabetes and obesity, where gastroparesis and altered transit compound glycemic control problems and energy dysregulation.
Lastly, gut bacteria convert choline and carnitine from meat and eggs into trimethylamine (TMA), which the liver converts to TMAO, a metabolite linked to cardiovascular disease. The paper notes the transit-TMAO link hasn’t been fully characterized yet, but it’s a plausible pathway to worsened heart disease.
Thanki: Colorectal cancer is one of the most well-established and serious associations with chronic constipation.
Slow transit promotes the accumulation of secondary bile acids that are directly genotoxic and cytotoxic to colonocytes.
Combined with the shift toward proteolytic fermentation generating ammonia, phenols, and hydrogen sulfide — all of which damage the mucosal barrier and colonocyte DNA — and the depletion of protective butyrate (a SCFA), the colonic environment becomes progressively more hostile over time.
The distal colon, where proteolysis dominates and transit is slowest, is also where most colorectal tumors arise.
Thanki: Eat lots of fiber (I suggest aiming for 35 g a day), drink lots of water (64 to 80 ounces a day), and minimize red and processed meats (3 portions of red meat a week and only eat processed meats rarely or sparingly).
Try to get your fiber from varied sources like vegetables, seeds, and whole grains, and don’t hesitate to take a fiber supplement like psyllium husk.
Probiotic foods like yogurt, kefir, kombucha, and sauerkraut can help restore gut flora, especially sugar-fermenting bacteria.
Finally, exercise! Even 20 to 30 minutes of walking a day will stimulate your gut motility.
Thanki: Think beyond your diet — while food and water intake are major contributors, constipation is multifactorial.
Move your body regularly: Even a daily 20 to 30-minute walk can stimulate bowel activity.
Don’t hold in your bowel movements: Ignoring the urge to defecate retrains your bowel to live with constipation.
Try lifestyle modifications to help with stress, poor sleep, and reduce medications that might slow things down. These can all contribute to nervous system and hormonal dysregulation that, in turn, affects gut motility.
If constipation persists for more than a few weeks despite lifestyle modification, there’s likely something more going on. Listen to your body and get it checked out.
Thanki: Chronic diarrhea accelerates gut transit to the point where adequate nutrient absorption and microbial fermentation cannot occur, leading to a cascade of long-term systemic consequences, including:
The persistently compromised gut barrier allows bacterial products to enter systemic circulation, driving low-grade inflammation linked to autoimmune conditions, while the depleted SCFA production starves colonocytes and further destabilizes the mucosal lining.
Control is one of my favorite adventure games of the last decade or so, a mind-bending trip through an ever-changing building where you get to use telekinesis to battle some pretty freaky enemies. It was a graphically-demanding game when it was released in 2019, but a lot can change in less than six years: Control: Ultimate Edition is now available on the iPhone and iPad for a mere $5, following its announcement last October. It’s a universal purchase, which means if you buy it it’ll work on the iPad, iPhone and Mac as well.
Developer Remedy promises that it’s the full Control experience, with the DLC episodes included. Remedy rebuilt the UI and controls to make it work on touchscreen devices; the company says that it has tweaked aiming and the various puzzles to make them work better for the iPad and iPhone. But naturally, the game also works with controllers. If you’re serious about having the best experience with the game, finding a way to play with physical controls is probably a good idea.
The game will run on iPhones with at least an A17 Pro chip. That includes the iPhone 15 Pro and Pro Max, as well all of the iPhone 16 and iPhone 17 series. Plenty of iPad models can run the game, as well — any iPad with an M-series chip or the A17 Pro will work. That means the current basic iPad, with its A16 processor, is left out of the fun. But any iPad Air or Pro from the last four years or so should be good to go.
I tried a test version of Control when I reviewed the new iPad Air recently and, unsurprisingly, the tablet’s M4 chip was more than powerful enough to make for a smooth experience. My main gripe is that when sprinting, you have to hold down the L3 button the entire time you’re running rather than just click it once, which is how it works on other platforms. Otherwise it looks and plays smoothly, though I can’t vouch for how it’ll perform on hardware older than the M4 from 2024.
Control marks the latest “AAA” title to hit the iPad and iPhone. Apple has aggressively courted developers for its platforms in recent years, and while most games don’t hit the Mac or iOS when they launch, more and more are showing up eventually. There are multiple recent Resident Evil titles for the iPad, and other games like Death Stranding and Assassin’s Creed Mirage have been ported recently as well. There are others on the Mac as well, including demanding titles like Cyberpunk 2077 and Lies of P. Apple’s platforms aren’t going to be an avid gamer’s first stop still, but having high-profile games to supplement the many indie titles available helps round out the options for Apple users.
In a recent development, giant market maker GSR announced its official entry into the ETF space today by launching its first ETF.
GSR’s GSR Crypto Core3 ETF has begun trading on Nasdaq under the ticker symbol BESO. The fund includes investments in Bitcoin ($BTC), Ethereum ($ETH), and Solana ($SOL).
The GSR Crypto Core3 ETF will invest in $BTC, $ETH, and $SOL and accumulate staking rewards where applicable.
According to the announcement, BESO is the first actively managed multi-asset cryptocurrency exchange-traded fund (ETF) in the US to offer staking capabilities.
GSR CEO Andy Baehr said the following:
“Core3 answers three questions that every crypto investor faces: what to own, how to generate returns while holding, and how to position yourself as markets evolve?”
As cryptocurrencies become an increasingly important component of modern portfolios, Core3 provides exposure to the fundamental drivers of this asset class.
GSR’s launch comes amidst rapid growth in the cryptocurrency ETF market. Since the approval of spot Bitcoin and Ethereum ETFs in 2024, ETF products have rapidly expanded, attracting traditional finance firms such as Morgan Stanley and Goldman Sachs.
Baehr said that GSR’s move signals its expansion beyond market making into asset management and capital market services.
As oversight of the cryptocurrency market in the UK tightens, the Financial Transactions Authority (FCA) has carried out its first comprehensive operation against illicit peer-to-peer (P2P) crypto transactions. The agency announced that it conducted joint raids targeting eight different locations across London.
The FCA conducted the operation in conjunction with HM Revenue & Customs and the South West Regional Organized Crime Unit. Inspections at suspected addresses uncovered evidence of illegal activity, and official warnings were issued to the individuals and businesses involved to cease their operations. The collected evidence reportedly supports several ongoing criminal investigations.
Peer-to-peer crypto trading involves users trading directly with each other instead of through a centralized exchange. However, according to the FCA, registration is required for such activities to be legally conducted. The agency emphasized that there are currently no registered P2P crypto trading platforms or individual providers in the United Kingdom.
Steve Smart, an FCA official, stated that individuals operating off the books are engaging in illegal activities and increasing the risk of financial crime. Similarly, law enforcement officials have pointed out that such operations can be used for money laundering and illicit fund transfers.
Experts say this step is part of the FCA’s strategy to expand cryptocurrency oversight. While comprehensive crypto regulations are expected to come into effect in the country by 2027, existing rules, particularly anti-money laundering obligations, are already in place.
Virginia man’s before-bed routine leads to a $200,000 lottery prize
March 26 (UPI) — A Virginia man’s routine of playing online lottery games to relax after putting his kids to bed resulted in his winning a $200,000 jackpot.
The Malta Film Commission is putting the pieces together for a fourth installment of its Mediterrane Film Festival, set to take place on the island’s capital city of Valletta from June 21-28.
It may be hard to top last year’s event — a milestone moment for Malta that celebrated the island’s 100-year history as a filmmaking hub dating back to the first production that shot there, 1925’s Sons of the Sea — but festival director Pierre Agius and curator Mark Adams have a plan in place for the program, anchored by the theme “Beyond Together.”
The film program will expand from three to five strands: Big Screen Competition featuring the best of mainstream cinema, Mediterranean Competition featuring new cinema from the Mediterranean region with a spotlight on local stories and talent, Mare Nostrum for films with an environmental message, Best of the World for new cinema from around the world to Malta and Malta Focus for specifically local films (shorts and features) that highlight island talent.
Also on the horizon will be screenings followed by filmmaker Q&As that will take place at Valletta’s Embassy Cinema, events at two outdoor screening venues, Upper Barrakka Gardens and Fort Ricasoli Counterguard, and other custom programming, panels and masterclasses from boldfaced names. Previous speakers include filmmaker Mike Leigh, editor Yorgos Mavropsaridis, Oscar-winners Nathan Crowley and Rick Carter, filmmaker Catherine Hardwicke, casting director Margery Simkin, and blockbuster filmmakers Jon Watts and Jake Schreier.
Competition titles will be screened by a jury of creatives, tasked with selecting the winners of the Golden Bee Awards. The honors will be doled out at a gala on June 28. Russell Crowe turned up last year to accept a film legend award, underscored by his work in Gladiator, which filmed in Malta.
“The Mediterrane Film Festival continues to grow as a platform that connects Malta to the global film industry. Furthermore, it continues to reflect Malta’s long-term vision for film infrastructure, including the development of the land-sea super stage,” explained Malta Film commissioner Johann Grech, who last year played host to a variety of production insiders to promote the island’s rich 40 percent tax rebate incentive to keep cameras rolling in 2025 and beyond. “With the 2026 edition, we are not only expanding the Festival’s programme, but strengthening its role as a meeting point for talent, ideas, and opportunity. ‘Beyond Together’ reflects exactly where we are heading — building partnerships, attracting productions, and positioning Malta as a serious and competitive player in the international film landscape.”
Added Agius: “Our focus for 2026 is clear — to elevate both the audience experience and the industry relevance of the Festival. By expanding the programme and strengthening our international collaborations, we are creating a Festival that is both culturally meaningful and globally connected.”
Ticket sales for all screenings will be donated to the local Maltese cancer charity Puttinu Cares.
It was 1983, and a 26-year-old producer named Brian Grazer was sitting across from the most feared man in Hollywood.
Ray Stark had a rival mermaid movie loaded with Warren Beatty, Jessica Lange, Herbert Ross directing and Robert Towne writing the script. Grazer had a scrappy fairy tale at Disney — a studio whose most recent live-action release was Gus, a flop about a field goal-kicking mule — and a leading man whose cross-dressing sitcom had just been canceled.
Stark’s message was simple.
“He threatened to just crush me,” Grazer says. “That I ‘Have nothing. Nothing.’ They’d ‘kill’ me.”
Then came the offer: 5 percent of the first-dollar gross if Disney would kill Splash. Disney said no, however, and Splash opened March 9, 1984. It became a top-10 hit, made Tom Hanks a movie star overnight, invented the Touchstone label, cracked March open as a release window, birthed Imagine Entertainment and gave the English language a new girl’s name: Madison.
Sitting down with It Happened in Hollywood, Grazer and Ron Howard lay out how one of the great sleeper hits of the decade almost never existed — and how close it came, repeatedly, to disappearing.
The origin is pure Grazer: At 25, producing a TV movie on Zuma Beach, he spotted “the hottest girl at USC, literally,” who had never given him the time of day. Then someone whispered: That’s the producer. “Seconds later, she’s asking me out,” he recalls.
A parade of newly interested women followed. Grazer found it clarifying, if vexing. Were they into him for him — or for what he could do for them? He went home and wrote down, literally, the attributes of someone who might actually love him back.
“That became the mermaid,” he says.
The script bounced through United Artists, Warner Bros. and nearly every studio in town. Nobody wanted to touch it. Not with Beatty circling and the powerful Stark looming. Executives didn’t say no —they just vanished.
Eventually, the project landed at Disney — a move that, at the time, felt like a step down. This was pre-Renaissance Disney. Howard for one wasn’t convinced.
“That is really the minor leagues,” he recalls thinking.
But Disney was eager, on one condition: the mermaid needed a bikini top.
“That was a no-go,” Howard says. What followed was a surreal pitch to Disney’s seven-person board, where Grazer found himself explaining mermaid logic to chairman Card Walker. The compromise — long hair, body stocking, no visible nudity — got them over the line.
Then Stark called. When the bribe didn’t land, the pressure shifted to Disney chairman Ron Miller, Walt Disney’s son-in-law and, as Grazer puts it, “a tough guy.”
His response, per Grazer: “We’re doing it anyway. Fuck you. “
Now they had a greenlight — and a race. Howard, coming off Night Shift, promised he’d beat Ross to theaters. “I’m 26 years old. He’s not going to beat me,” he remembers telling them.
Grazer remembers it more vividly: “You said you’d be like a military grunt climbing under barbed wire.”
Howard shrugs. “Yeah, I probably did.”
But Ross’s movie never materialized. Splash did.
The casting followed the same pattern: almost everyone said no. John Travolta passed. Richard Dreyfuss passed. Others declined without meetings. One agent reportedly sneered that his client would “never act in a movie with Ron Howard and Tom Hanks.”
Tom Hanks, at that point, wasn’t Tom Hanks. He auditioned for the brother role — the John Candy part — after a tip from writer Lowell Ganz. “He was crackling with intelligence,” Howard says. After the audition, Howard and Grazer looked at each other. “Could he be the lead?” they both wondered. Grazer went in and sold it.
As for the mermaid, Daryl Hannah had already made an impression in Blade Runner. Then she walked in and said she’d spent her childhood practicing underwater breathing with a garden hose. “I’ve dreamed of being a mermaid all my life,” she told them, landing her the part.
She also got sealed into a custom tail that took hours to remove, swam without a mask and outperformed professional “mermaids” in test tanks. Bathroom breaks were not an option.
The shoot itself was controlled chaos. The East River jump required stunt performers to be inoculated against typhus. (“Then, you could get typhus,” Howard notes.) At the Statue of Liberty, they had to wrap before the first ferry arrived. Howard had a 102-degree fever. They pulled off 63 setups before 7:45 a.m.
Splash: Tom Hanks and Daryl Hannah in the 1984 feature.
Courtesy Everett Collection
And then there’s the lobster scene. Hannah, a strict vegetarian, was handed a fake lobster stuffed with string cheese and potatoes. It didn’t work. Howard demonstrated by biting into a real claw. Hannah tried once, screamed and dropped it. Then she did it again; that’s the take in the movie.
By the time exhibitors saw Splash, the reaction flipped instantly. (“They all wanted it,” Grazer says.) The film opened in March — a dead zone at the time — and became a top-10 hit. Disney created Touchstone to release it. March became viable. High-concept comedy got a new blueprint. And “Madison,” pulled from a Manhattan street sign, became one of the most popular baby names in America.
The closest Grazer came to quitting wasn’t Stark. It was the slow accumulation of rejection. “I was so embarrassed,” he says, recalling how people would actively avoid him at social events, worried he’d try to sell them on his “mermaid movie.”
What kept him going, improbably, was Steven Spielberg — who had E.T. put into turnaround, as star Henry Thomas detailed in another recent episode of It Happened in Hollywood, whose current season is taking a closer look at the magical films of 1980s.
“I thought, this guy made Jaws and Raiders. I can’t take this personally,” Grazer says.
Howard’s memory of the shoot is almost the opposite of the fight to get there.
“It was one of the least stressful movies I’ve ever made,” he says. “Once we were rolling, it was working.”
The full episode of It Happened in Hollywood with Brian Grazer and Ron Howard is available now on Apple Podcasts, Spotify and wherever you get your podcasts. Splash is streaming on Disney+.
Mozilla says Anthropic’s Claude Mythos identified 271 vulnerabilities in Firefox during testing.
Anthropic is restricting the model to vetted partners through Project Glasswing because of cybersecurity risks.
Researchers warn that the same capability could accelerate automated cyberattacks.
For decades, attackers have had the advantage in cybersecurity. Artificial intelligence may be about to change that.
In a blog post published on Tuesday, Firefox browser developer Mozilla said an early version of Anthropic’s Claude Mythos AI—which has drawn attention in recent weeks for its purported cybersecurity prowess—model helped identify 271 vulnerabilities in the browser during internal testing. Those bugs were patched this week.
The results highlight how advanced AI systems can analyze large codebases and locate weaknesses that previously required extensive manual review by human cybersecurity researchers.
“As these capabilities reach the hands of more defenders, many other teams are now experiencing the same vertigo we did when the findings first came into focus,” Mozilla wrote. “For a hardened target, just one such bug would have been red-alert in 2025, and so many at once makes you stop to wonder whether it’s even possible to keep up.”
Mozilla had earlier tested another Anthropic model that identified 22 security-sensitive bugs in a previous Firefox release. Despite these successes, Mozilla acknowledged that the cybersecurity industry has long treated the complete elimination of software exploits as an “unrealistic goal.”
“Until now, the industry has largely fought security to a draw,” the company wrote. “Vendors of critical internet-exposed software like Firefox take security extremely seriously and have teams of people who get out of bed every morning thinking about how to keep users safe.”
Mozilla said the new AI system can analyze source code and identify vulnerabilities in ways that previously depended on scarce human expertise. However, Mozilla said the company was encouraged to see that no bugs were found that couldn’t have been discovered by “an elite human researcher.”
“Some commentators predict that future AI models will unearth entirely new forms of vulnerabilities that defy our current comprehension, but we don’t think so,” they said. “Software like Firefox is designed in a modular way for humans to be able to reason about its correctness. It is complex, but not arbitrarily complex.”
The results, however, suggest AI tools could allow developers to uncover large numbers of vulnerabilities before attackers exploit them—though conversely, in the wrong hands, it could spell big trouble for software firms and users alike.
Launched in March, Mythos is Anthropic’s most advanced model for reasoning, coding, and cybersecurity tasks. Internal company materials describe the system as part of a new model tier beyond the company’s earlier Opus series.
Testing conducted before the model’s release showed it could identify thousands of previously unknown vulnerabilities across major operating systems and web browsers.
Anthropic has limited access to the system through a restricted program called Project Glasswing, which gives select technology companies—including Amazon, Apple, and Microsoft—the ability to use the model to scan software for weaknesses. It reflects a growing effort within the cybersecurity industry to use AI systems to identify and patch vulnerabilities before attackers can exploit them.
However, the same technology could also enable new forms of cyberattacks. Security researchers say AI systems capable of analyzing code at scale could automate the discovery of exploitable vulnerabilities across widely used software.
After the launch of Mythos, testing by the U.K.’s AI Security Institute found that the AI could autonomously execute complex cyber operations, including completing a multi-stage corporate network attack simulation without human assistance. Those capabilities have drawn attention from governments and intelligence agencies alike.
Despite a call from President Donald Trump’s administration to stop using Anthropic’s technology due to a clash over its use in war and surveillance matters, on Monday, the National Security Agency was revealed to be running Claude Mythos Preview on classified networks, according to sources familiar with the deployment. The use of Mythos underscores the growing interest among U.S. security agencies in the model’s ability to identify critical software vulnerabilities.
The model’s performance has also exposed limits in existing AI evaluation systems. Earlier this month, Anthropic acknowledged that several cybersecurity benchmarks are no longer sufficient to measure the capabilities of its newest models.
Mozilla said the results point to a potential shift in cybersecurity, where defenders may begin to close the long-standing advantage attackers have held.
“We are extremely proud of how our team rose to meet this challenge, and others will too,” Mozilla wrote. “Our work isn’t finished, but we’ve turned the corner and can glimpse a future much better than just keeping up. Defenders finally have a chance to win, decisively.”
Mozilla did not immediately respond to a request for comment by Decrypt.
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United States President Donald Trump has claimed that a new nuclear deal being negotiated with Iran will be “far better” than the 2015 Joint Comprehensive Plan of Action (JCPOA), which the US withdrew from in 2018 during his first term.
On Tuesday, Trump extended the two-week ceasefire with Iran a day before it was set to expire, with hopes for a second round of talks in Islamabad, Pakistan.
Key among the US demands is that Iran stop all enrichment of uranium.
Iran has always insisted its nuclear programme is for civilian use only, such as for power generation, which requires uranium enrichment of between 3 percent and 5 percent. To build nuclear weapons, uranium needs to be enriched to 90 percent.
In this explainer, we visualise what uranium is, how it is enriched and how long it could take Iran to make a nuclear weapon.
What is uranium, and which countries have it?
Uranium is a dense metal used as a fuel in nuclear reactors and weapons. It is naturally radioactive and usually found in low concentrations in rocks, soil and even seawater. About 90 percent of the world’s uranium is produced in just five countries: Kazakhstan, Canada, Namibia, Australia and Uzbekistan. Reserves of uranium have also been found in other countries.
Uranium is extracted either by digging it out of the ground or, more commonly, through a chemical process that dissolves uranium from within the rock.
Before it can be used as nuclear fuel, uranium is processed through several different forms, including:
Yellowcake: Mined ore is crushed and treated with chemicals to form a coarse powder known as yellowcake, which, irrespective of its name, is usually dark green or charcoal in colour, depending on how hot it has been treated.
Uranium tetrafluoride: Yellowcake is then treated with hydrogen fluoride gas, which turns it into emerald-green crystals known as uranium tetrafluoride or green salt.
Uranium hexafluoride: Green salt is further fluorinated to create a solid white crystal known as uranium hexafluoride. When heated slightly, this crystal turns into a gas, making it ready for enrichment.
Uranium dioxide: The gas is spun in a centrifuge machine, which chemically converts it into a fine, black powder.
Fuel pellets: The black powder is pressed to form black ceramic pellets, which can then be used in a nuclear reactor.
How is uranium enriched?
Natural uranium exists in three forms, called isotopes. They are the same element, with the same number of protons but different numbers of neutrons.
Most naturally occurring uranium (99.3 percent) is U-238 – the heaviest and least radioactive – while about 0.7 percent is U-235 and trace amounts (0.005 percent) are U-234.
To generate energy, scientists separate the lighter, more radioactive U-235 from the slightly heavier U-238 in a process called uranium enrichment. U-235 can sustain a nuclear chain reaction while U-238 cannot.
To enrich uranium, it must first be converted into a gas, known as uranium hexafluoride (UF₆). This gas is fed into a series of fast-spinning cylinders called centrifuges. These cylinders spin at extremely high speeds (often more than 1,000 revolutions per second). The spinning force pushes the heavier U-238 to the outer walls, while the lighter U-235 stays in the centre and is collected.
A single centrifuge provides only a tiny amount of separation. To reach higher concentrations – or “enrichment” – the process is repeated through a series of centrifuges, called a cascade, until the desired concentration of U-235 is achieved.
What are the different levels of uranium enrichment?
The higher the U‑235 percentage, the more highly enriched the uranium is.
Small amounts (3-5 percent) are enough to fuel nuclear power reactors, while weapons require much higher enrichment levels (about 90 percent).
The International Atomic Energy Agency (IAEA) considers anything below 20 percent to be low-enriched uranium (LEU), while anything above 20 percent is considered highly-enriched uranium (HEU).
Low enriched – less than 20 percent
Commercial grade – 3-5 percent: This is the standard fuel for the vast majority of the world’s nuclear power plants
Small modular reactors – 5-19.9 percent: Used in more modern reactors and advanced research reactors
Highly enriched – More than 20 percent
Research grade – 20-85 percent: Used in specialised research reactors to produce medical isotopes or to test materials
Weapons grade – above 90 percent: This is the level required for most nuclear weapons
Naval grade – 93-97 percent: Used in the nuclear reactors that power submarines and aircraft carriers
Depleted uranium, which contains less than 0.3 percent U‑235, is the leftover product after enrichment. It can be used for radiation shielding or as projectiles in armour‑piercing weapons.
How long does it take to enrich uranium?
The effort it takes to enrich uranium is not linear, meaning it is much more difficult to go from 0.7 percent natural uranium to 20 percent LEU than it is to go from 20 percent to 90 percent HEU. Once uranium reaches 60 percent enrichment, it becomes much quicker to reach 90 percent weapons grade.
The effort it takes to enrich uranium is measured in separative work units (SWU).
According to the IAEA, Iran is believed to have about 440kg (970lbs) of uranium enriched to 60 percent – enough to theoretically build 10 or 11 low-technology atomic bombs if refined to 90 percent.
The then-President Mahmoud Ahmadinejad inspecting the Natanz nuclear plant in central Iran, March 2007 [Handout/Iran President’s Office via EPA]
Ted Postol, professor emeritus of science, technology and international security at the Massachusetts Institute of Technology (MIT), told Al Jazeera that before the US attack on Iran’s nuclear facility at Fordow, the country had at least 10 cascades of 174 IR-6 centrifuges in operation – meaning 1,740 IR-6 centrifuges.
The IR-6 is one of Iran’s most advanced centrifuge models. The country also has tens of thousands of older centrifuges.
Little is known about the conditions of these centrifuges or the stocks of uranium hexafluoride, which are still believed to be buried underground.
Postol has calculated that Iran’s cascade of centrifuges could produce 900 to 1,000 SWUs annually.
“Getting from natural uranium to 60 percent enrichment, which Iran has already achieved, takes roughly five years, and about 5,000 SWUs using Iran’s cascades.”
“If I want to go from 60 to 90 percent, I only need 500 SWUs. So, instead of five years, [by] starting with the 60 percent here, this might take me four or five weeks. Because I am already very enriched,” Postol said.
Using an analogy of a clock, Postol explained: “Let’s say it takes seven minutes to get 33 percent enrichment, and then eight minutes to get to 50 percent enrichment. It only takes me one minute to get to total [90 percent] enrichment.”
How easy would it be for Iran to build a nuclear weapon?
Postol said Iran’s stockpile is held underground, meaning a military strike would not necessarily eliminate the nuclear threat.
A single centrifuge cascade capable of enriching weapons-grade uranium could take up “no more floor space than a studio apartment, making it easily hidden in a small laboratory”, he said, estimating the area at 60sq metres (600sq feet).
“A single Prius Compact Hybrid car can produce enough electric power to run four or more of these cascades at a time,” Postol added, meaning “Iran can covertly convert its 60 percent uranium into weapons-grade uranium metal”.
“What they have done is put themselves in a position where anybody who thinks about attacking them with nuclear weapons has to know that they could be sitting in those tunnels after such an attack, refining [and] enriching the final step they need to build atomic weapons and converting it to metal, and building a nuclear weapon, and that they have the means to deliver it,” Postol said.
“They would have all of the technical equipment they need to build the atomic weapons. And they have the missiles, which are also in the tunnels and can be manufactured in addition to what they already have. And the atomic weapon would not need to be tested, because uranium weapons do not need to be tested before they’re used.”
What does the NPT say about enrichment?
The Treaty on the Non-Proliferation of Nuclear Weapons (NPT), established in 1968, is a landmark international agreement aimed at preventing the spread of nuclear weapons and promoting peaceful uses of nuclear energy. Iran is a signatory to this pact.
The treaty supports the right of all signatories to access nuclear technology and enrich uranium for peaceful purposes, including energy, medical or industrial purposes, with precise safeguards to ensure it is not diverted to make weapons.
Under the NPT, nuclear-weapon states agree not to transfer nuclear weapons or assist non-nuclear-weapon states in developing them. Non-nuclear-weapon states also agree not to seek or acquire nuclear weapons.
Despite this, most nuclear powers are currently modernising their arsenals rather than dismantling them.
Most of the countries are signatories, except five: India, Pakistan, Israel, South Sudan and North Korea.
What agreements has Iran made about its nuclear programme in the past?
In 2015, under the Obama administration, Iran struck a deal with six world powers — China, France, Germany, Russia, the United Kingdom and the US — plus the European Union, known as the JCPOA.
Under the pact, Tehran agreed to scale down its nuclear programme, capping enrichment to 3.67 percent, in exchange for relief from sanctions.
“The Iranians agreed to it, and they were following the treaty. There was no problem with the treaty at all, absolutely no problem,” Postol said.
“They were allowed to have 6,000 centrifuges, which, if they had natural uranium, they could probably build a bomb within a year if they were secretly using these centrifuges, but that was all under inspection. They were just simply going to enrich to 3.67 percent, which is for a power reactor. They’re allowed to do that by the Non-Proliferation Treaty.”
But in 2018, Trump pulled out of the deal, calling it “one-sided” and reimposing sanctions on Iran. Iran responded by eventually resuming enrichment at Fordow.
After the US killed Iran’s General Qassem Soleimani in January 2020, Tehran stated it would no longer follow the set uranium enrichment limits.
Former President Joe Biden made attempts to revive the deal, but it never came to fruition due to disagreements over whether sanctions should be lifted first or Iran should rejoin the JCPOA first.
Trump has repeatedly said Iran should not have the ability to produce nuclear weapons. It has been one of Washington’s red lines during talks with Iranian officials over the past year, and was also the central justification that Washington used when it bombed Iranian nuclear facilities during the 12-day US-Israel war on Iran last year.
In the current negotiations, Iran has said it is willing to “downblend” its 60 percent enriched uranium to about 20 percent – the threshold for low-enriched uranium. The process of downblending involves mixing stocks with depleted uranium to achieve a lower percentage of enriched U-235 overall.
“From the point of view of showing goodwill, I think it’s good, it shows that the Iranians are thinking of ways to address what the Americans claim are their concerns,” Postol said.
Which countries have nuclear weapons?
Nine countries possessed roughly 12,187 nuclear warheads as of early 2026, according to the Federation of American Scientists. Approximately two-thirds are owned by two nations – Russia (4,400) and the US (3,700), excluding their retired nuclear arsenals.
Some 9,745 of the total existing nuclear weapons are military stockpiles for missiles, submarines and aircraft. The rest have been retired. Of the military stockpile, 3,912 are currently deployed on missiles or at bomber bases, according to the Federation of American Scientists. Of these, some 2,100 are on US, Russian, British and French warheads, ready for use at short notice.
While Russia and the US have dismantled thousands of warheads, several countries are thought to be increasing their stockpiles, notably China.
The only country to have voluntarily relinquished nuclear weapons is South Africa. In 1989, the government halted its nuclear weapons programme and began dismantling its six nuclear weapons the following year.
Israel is believed to possess nuclear weapons, with a stockpile of at least 90. It has consistently neither confirmed nor denied this, and despite numerous treaties, it faces little international pressure for transparency.
