Five years ago, Brené Brown was an obscure academic – an associate professor of social work at the University of Houston – and then, overnight, she was famous. She was “the vulnerability woman” or “the shame academic”, and it’s a measure of how much her life has changed that during a whistlestop few days in Britain she has had a private leadership session with banking executives in the City, an evening in front of a capacity crowd at Alain de Botton’s School of Life, an all-day workshop training counsellors in her methodology, and a whole string of interviews to mark the launch of her latest book, Rising Strong.

On the one hand she’s now reaching the kind of audience that most academics can only dream of. On the other she seems, well, a bit exhausted. A photo shoot was scheduled for after my interview, but when I catch up with her in her London hotel she explains that she has pulled out because it was just “too much”. Part of the problem, she says, is that “it’s not me. I’m a researcher. It also… to be totally frank with you, I actually don’t like the cult of personality celebrity stuff around my work at all. It should be about the work, right? I’m not that interesting. The work is really interesting – the work is the research.”

In fact this cuts to the heart of the conundrum that is now Brown’s life. She’s still an academic. But she’s now also an Oprah-approved author who gigs on the global megaspeaker circuit. Making sense of these two things seems to be an ongoing struggle. She hates the words “self-help”, she says. “I don’t know what it means. I don’t think we’re meant to do it alone. And I think I have a really legitimate reflex to those words as a researcher. I do walk through [bookshop] aisles sometimes and say: ‘Jesus, where’s the evidence to support this?’”

And yet the text underneath Rising Strong’s title, plastered across the cover, is pretty unequivocal: “If we are brave enough, often enough, we will fall,” it says. “This is a book about getting back up.” She may not want to see herself as a self-help author, but her publishers certainly do. And at least it means people are now reading her work – her last two books were both bestsellers.

And all because, back in 2010, she agreed to give a talk to a few hundred people at a small TEDx event in Texas. It was on her specialist subject: vulnerability and its partner in crime, shame. She’s a qualitative researcher, so her work involves interviewing people and listening to their stories, and after hundreds of interviews she thought she’d found some common threads: that connection is the key to everything, but shame – or a fear of disconnection – keeps us from it. She discovered, however, that there was a class of people who simply felt good enough, who weren’t plagued by fear or doubt. And the key, she theorised, is that they were able to be vulnerable. The problem, she realised, was that it didn’t include her. She had been on “a mission to control and predict”, but this had led her to research “which suggested that the way to live is with vulnerability and to stop controlling and predicting”. The result, she told the audience, was a breakdown.

Later she told a friend how embarrassed she was that she’d opened up like that and how terrified she was that the talk would be put online where “up to 500 people” might see it. Or, imagine, a thousand. “My life would be over,” she said. But a few more than that did – the video went viral and now more than 23 million people have watched it. The “warm wash of shame” as she calls it, of not feeling good enough, or smart enough, or thin enough, was something that people everywhere could relate to. And if talking about feelings sounds a bit warm and fuzzy, there’s an edge to what Brown says, a wit. She’s warm, but she’s also forthright and funny. A fifth-generation Texan whose family motto is “lock and load”.

Why do you think it spoke to people so much, I ask her towards the end of our interview. “Interestingly or ironically, the willingness or the courage to articulate what I’m feeling exactly right now,” she says. “Which is: do the best work you can and find the courage to put your work out there and know that, no matter what you do, some people are going to like it and some people aren’t. All you can really control is how you feel about what you’ve contributed. The thing was to say out loud how hard that really is: ‘I want to be brave with my work and I want to be brave with my life.’ People will find a million reasons to tear it down, so you have to be really sure about what you’re doing, because in the end, if you believe in it that’s enough.”

It’s quite a speech – both heartfelt and a bit defiant – and it’s a reaction to a series of questions I’ve asked her. Doesn’t it put too much onus on the individual, I ask. Given that many people have problems – such as being poor – which they can’t necessarily fix by being vulnerable or courageous? And has there been independent research into whether her theories actually work? Because as well as the three books she’s written, she’s also spun two companies out from her research: CourageWorks, an e-learning course, and the Daring Way, a certification course for counsellors. And while it’s understandable that you are uncomfortable with “the cult of personality”, people are buying into your personality, aren’t they? They believe you can help them.

“I have a strong belief in a lot of things,” she says, “like union work, and I don’t know anything about the people who founded them. I’m just more interested in the theory. To me, in many ways I’m the face of it because it’s my work, but I think people have a hard time straddling the tension of the fact that you can be both accessible and a researcher. Especially in this country.”

I don’t know, I say. Daniel Kahneman is an academic, but also a massive seller, I can straddle that tension, but you’ve commercialised your research – you’re offering a course that costs $4,000, so there’s a higher bar. It’s a business, not just a theory, right? It begs different questions.

Her response is interesting: “You’re referring to the Daring Way, but $4,000 plus or minus $100 is what it costs us to put someone through training. The Daring Way was about an ethical decision. How can we make sure we can refer people who understand the research and work from an empirically based practice model? In order to do that we had to get very serious about the vetting, which is unusual for training certification. It’s definitely a labour of love, not commercial.

“And CourageWorks, my other company,” she adds, “is really all about scaling. I was on Necker Island with Richard Branson and a lot of social activists, and at the end he invited a bunch of local high-school seniors. And afterwards Richard asked some of the kids: ‘What could make your life better here?’ Two of them said: ‘Had I grown up in a family where my parents had an understanding of what shame was, and how it should or shouldn’t be used as a parenting tool, my life would be different.’ I thought: we should be able to do that. We have technology. We should be able to get this everywhere, make learning accessible. And if people find that to be commercialisation, which makes me less of a scholar or less of a contributor, that’s about their stuff.”

Maybe it is about their stuff, or in this case, my stuff. On the one hand she’s dealing with the universals of human experience and has genuinely interesting things to say. On the other there’s the schmaltzy subtitle and the folksy tone of Rising Strong – there’s a lot about “Wholeheartedness”, a term she’s coined, and believing people are Doing The Best That They Can. It’s not my thing, but so what? There’s no doubt she’s reaching a large audience that finds value in what she’s saying.

Brown believes that we are in an “epidemic of shame”, shame that expresses itself in alcoholism and obesity and addiction and debt and medication, but she claims that its expression is gendered. That for men and women the triggers are different. For women it’s about expectations and, often, body image. For men it’s about being perceived as weak.

And yet… and I struggle to put this diplomatically, the presentation of her work seems pretty gendered. Brown’s Instagram page majors heavily on the kind of inspirational quotes in cutesy typography set against pretty pictures that bring me out in a rash. “Show up. Be seen. Be loved,” says a typical one. “#LoveWins”

“I don’t think there is a gender difference in my work,” she says. “Daring Greatly [the last book] had a readership which was about 50/50 men and women. And 75% of the people who invite me to talk to organisations are men. I will tell you, though, in Britain they want to put me on the cover of the book. And there was an article in one of the magazines here, and it was like: ‘America’s got a new self-help queen.’ To which my response is really: ‘Fuck you’, to be honest with you. It’s probably meant to be really nice, but I’m not sure.”

I guess that there’s an impression that there’s a sorority of women who are in this space, I suggest, talking about empowerment, all of whom are on Oprah, and it seems very female-centred, so there’s you and Elizabeth Gilbert and Amanda Palmer…

“I think it’s something I wrestle with a lot, because if you go to my talks the majority of the audience is women. Let me go on the record and say if you want to put me in an a room with Elizabeth Gilbert and Oprah and Amanda Palmer, I’ll take that date any day of the week. Amy Cuddy, Sheryl Sandberg, Susan Cain… bring them on – it’s great. I think the response to my work is gendered. I can guarantee this interview wouldn’t be anywhere close to what it’s been if I was a man sitting here. If I was a male researcher sitting here, I would not have to justify the commercialisation of my work. I would not have to justify trying to straddle the economy and popular culture. I would never be asked. Malcolm Gladwell, Dan Pink, Dan Ariely, they would not be asked.”

You’re accusing me of being sexist, I point out.

“No, I’m just saying that the response to my work is gendered.”

She says it’s funny because right now she’s in a collaboration with a Polaroid photographer, Andrea Corronna Jenkins, “and we’re doing these things called ‘Weekly doses of daring’. I spent a week and a half curating all of her photos for race, for class, for gender, for age. And because I put a pretty image up with words on it… I have to say, it’s super frustrating.”

What is? “The assumption that the powerful combination of beautiful images and words is just for women. What am I going to have? A bald eagle soaring with a dead rat in its talons with a quote saying: ‘Go work your balls off today, brother’?”

The publicist walks into the room right at that moment and Brown says: “Can we have a bit more time? We’re having a heated debate.”

And then, like women, perhaps, we both hastily backtrack and start heatedly agreeing with each other. The fact is that I like Brown and admire what she’s doing. Her whole schtick is about having the courage to be out there, doing stuff, and she is. I just don’t get on very well with words like “Wholeheartedness”, I say, especially when they’re capitalised.

“Me too,” she says and shrugs.

“It’s your phrase.”

“I don’t use it very much. I’d never say: ‘Wholehearted leadership’, for example.”

We’ve gone way over time. And by the end of it she looks even more exhausted. But she has a bigger issue. “That article that was written about me,” she says at the end. “The one where it said: ‘America Has a New Queen of Self-Help’? I’ve got to tell you, I cried for four hours, because I don’t think they’d ever do that to man who had been a researcher, a scholar, for 13 years. And it’s not unusual for me to be the only female speaker in a day-long list at a corporate event. With a predominantly male audience and to be paid half of what the men are. So I double my fee and then everybody leaps on me. Saying, who do you think you are? You know who I am? I’m the person trying not to vomit into my mouth when I hear what my male counterparts are making. That’s who I am. I’m just trying to stave off the throwing up. It’s difficult, difficult.”

It is. And maybe that could be a new quote for her Instagram page, set against a picture of an eagle with a dead rat in its talons. Brené Brown –Just Trying To Stave Off The Throwing Up.

Rising Strong is published by Vermilion at £12.99. To order a copy for £10.39, go to bookshop.theguardian.com