Cristina Junqueira helped build Brazilian fintech player Nubank into one of the world's largest digital financial services platforms.

Now, as she leads Nu's emerging US business, she is taking on its biggest challenge yet: breaking into America's crowded banking market.

As part of Business Insider's The Long Play, Junqueira sat down with Dan DeFrancesco, executive editor and anchor of Business Insider Today, to share her insights on how to build trust and scale in banking, like leaning into convenience through digital banking products.

During the discussion, called "Building a Global Challenger," Junqueira also talked about her plan to take on incumbents in retail banking.

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Winning is all about losing when it comes to weight-loss drugs. Eli Lilly thinks it has a REAL loser on its hands.

The pharma giant published results from its first clinical trial pitting retatrutide, a next-generation injectable medication awaiting regulatory approval, against Ozempic.

Patients with type 2 diabetes using retatrutide, or "reta" as some know it, lost, on average, more than twice as much weight (47 pounds) as those on the highest dose of Ozempic (21 pounds) during 16 months.

BI's Hilary Brueck has all the details on the trial here.

Dubbed "King Kong" or "triple G" because it mimics three different hormones, some believe the weight loss that users experience using reta could rival bariatric surgery.

Some of you might be well aware of reta. Even though it's still in clinical trials, copycat peptide sellers have flooded the gray market with knock-off versions. Gym bros, in particular, have praised the drug for its ability to shred fat quickly.

Another corner of the healthcare industry is touting a big push into AI.

Ro CEO Zach Reitano spoke to Hilary about the digital healthcare company's new AI agent.

(By the way, Zach is one of our speakers at The Long Play this afternoon! Follow our coverage here.)

Robin can leverage info like your prescriptions or wearable data to make health suggestions. That includes changing medication doses or schedules to reduce side effects.

Ro's push illustrates the race between healthcare companies and AI giants looking to use the technology to better serve their clients.

Companies like Ro benefit from being experts in the space and having easy access to patient data, but sometimes lack the technical know-how of their AI-based peers.

AI companies have the opposite problem. A powerful tech stack can lack subject-matter expertise.

The issue isn't specific to healthcare. It's taking place across industries, and it's why data has become such a premium.

But healthcare, with its privacy concerns, regulations, and high stakes (people's health!), makes it a tricky balance. OpenAI even has a doctor-whisperer to help it navigate AI's medical minefield.

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The problem of AI's impact on mathematicians is proving difficult to solve.

OpenAI solving a historically difficult math problem last month kicked off a wider debate about the role AI should play in mathematics.

Sam Altman tried throwing cold water on the AI-arithmeticians beef this week. He said mathematicians have largely gone from anger to acceptance about AI usage in the field.

But that sentiment doesn't quite track with some big names in the field who remain cautious about using the tech.

Terence Tao, a UCLA professor and math prodigy, isn't necessarily pessimistic about AI but also said the "romantic era" of math is over.

"We are entering an era where exciting new things are possible, but some things are being lost," he added.

AI's rapid disruption of mathematics is noticeable.

Shortly after publishing its solution to the Navier-Stokes equations, OpenAI solved an additional 700-plus math problems and released the data on GitHub.

NYU Math professor Tristan Buckmaster said OpenAI's solutions dump wiped out entire research programs.

Finding middle ground between the two sides is proving tricky.

The reaction to a student-run Caltech AI math event shows how seriously some mathematicians take the threat.

Caiman Moreno-Earle, a math major at Caltech, told BI's Truman Dickerson that seeing AI companies quickly solve these legendary math problems was "demoralizing."

It's why the 19-year-old decided to hold a "mathathon" where participants could use AI. Moreno-Earle even got Anthropic and OpenAI to each donate $1 million worth of computing power.

Then came the critics.

A letter garnering more than 700 signatories said the event "is likely to have destructive impacts for the mathematical community."

OpenAI eventually pulled out, but the event is still set to happen. Moreno-Earle maintains the mathathon was less about causing a stir and more about ensuring humans have a place in the field of mathematics in the AI era.

Some will argue mathematicians need to adapt to the times and newer tools. There was no point fighting to use a slide rule once the calculator arrived.

The way AI is going about upending the field is also ruffling feathers, though. AI's solutions aren't always clean or clear, requiring mathematicians to go back and verify its work.

And there are also questions about how AI is coming up with these solutions. Since some mathematicians brainstorm with AI models, some have speculated they're using their own work to front-run them to a solution.