The offices of UKTV, home to the channel Dave, is exactly what I expect a television company to look like – young people in fashionable glasses, brightly coloured furniture, creative-looking types thinking outside the box in glass meeting rooms. One is decorated with wood panelling and oil paintings, and Jo Brand is sitting here in a leather armchair, which puts me in mind of someone holding court in a gentleman's club, though she is more gentle and unassuming than that, her voice a low rasp. She is 54, but curiously ageless – I think it's the fact that she is still dressed like she was in the 80s and 90s when she made her name in standup comedy, in baggy black clothes and heavy boots, and possibly because she has just been talking about her two young children (her daughters are eight and 10).
We are joined in this tiny room by a publicist from the channel and someone from the production company, which creates a slightly strange, cramped atmosphere. It also means that I don't really feel able to say that I think her new show for Dave, Jo Brand's Big Splash, feels more like a paddle in the shallow end. Still, it doesn't matter that the concept is weak – essentially, getting Brand to humiliate herself in a variety of water-based situations – because I could watch her in anything.
It isn't just that she makes me laugh, it's more that she just seems – and I know this is uncool – such a good person. She turned down the Royal Variety Performance because she didn't want to be a hypocritical republican. She has never done adverts. Her hospital comedy series Getting On, which she co-writes and stars in, is brilliant, human and moving and makes up for the number of slightly rubbish shows she pops up on. Even these never seem to come from a place of attention-seeking and profile-raising – more that she has found some element of fun in them. In the first episode of Jo Brand's Big Splash, she dives for golf balls in the lake of a golf course, jumps off the high board with the Olympic diver Blake Aldridge, and takes part in the annual Maldon mud race (Brand flails around in the mire and calls someone from Blue Peter a "tosser").
So, it's entertaining enough and, anyway, hurrah for Dave – the blokey channel seemingly built on reruns of Top Gear and Mock the Week – for giving Brand her own show. "I know," she says, "letting a middle-aged, menopausal fat feminist on. It will be interesting to see whether Millwall fans turn off in their droves."
There are not enough middle-aged women on TV, she says. "I feel cheered by Miriam O'Reilly's stand against being removed from Countryfile." Writing Getting On, with its other actors Vicki Pepperdine and Joanna Scanlan, was partly a reaction to this. "It was the perfect way to have a cast of really interesting older women in a natural environment – a hospital – rather than setting it in a model agency."
Growing up, Brand had thought about being a comedian, but her mother said she should get a proper job, and so after a social sciences degree – and failing to get a job as a TV researcher – she trained to be a psychiatric nurse. It was a job she did for the next decade – ending up as head nurse at a 24-hour emergency psychiatric clinic, and getting out, she has said in the past, before it brutalised her.
Still, it was good training for the sometimes hostile world of standup. At an early gig, one heckler started shouting death threats and Brand quickly became expert in put-downs. "There have been some very extreme hecklers in audiences whose bile was so hateful and so meant that it would be a bit frightening to think that all I'm doing is jokes and yet someone hates me that much," she says. "I would never let on that it was hurtful because once they see a chink in your armour … so I would always come back and do this mouthy, aggressive, 'fuck you'-type thing."
For several years the tabloids sustained a monstering campaign, holding her up as a kind of non-woman entirely because Brand, with her heavy black boots and period jokes, refused to conform to a traditional femininity.
Oddly, Brand has always been the first to mock herself in often painful ways. Watching the beginning of this new show, I wondered how long it would be before she made a swimsuit joke. It was less than a minute – and they followed relentlessly. Brand has been making jokes about her weight ever since the mid-1980s. You can watch her first television appearance on YouTube, where she says: "I read that book Fat is a Feminist issue, got a bit desperate halfway through and ate it." I get why she did it back then – you need to make the obvious fat jokes yourself before the hecklers do (and make them funnier).
What I don't really get is why Brand does it now. Surely she has nothing to prove, no audience still to win over? "It's almost a thing that I can't stop because I've been doing it for so long," she says. With this show, especially, she adds, "when I spoke to a few friends about doing this, who are big, they said they hate this situation where to get fit and lose weight, you have to go somewhere wearing the absolute minimum of clothing. I have big friends who won't go swimming because they're too embarrassed about it. I feel that's such a shame, because actually people should be encouraging fat people who are exercising to do it, not pointing and laughing. I like to think, and I don't mean this in any sort of vain way, I say things for other people who are overweight and struggle with it."
What has changed for women in comedy since she started? She thinks for a moment. "There's a general sense that women are more relaxed and less defensive in comedy than they used to be. I think it's easier than it was but underlying it all there is still a pretty sexist view of women on stage, which to me hasn't changed that much."
I mention the rise of the rape joke – several comedians, not all male, have been increasingly using rape for laughs – and Brand grimaces. "Yes, I have noticed that. Obviously it's not something I'm happy about but it's not something I'm surprised about either. As the stock of taboos shrinks, so comedians branch out in different directions and do those sort of jokes. I would say to people to their face if they've done something I thought was awful – though I'm not saying it would have any effect whatsoever."
She did this to Jimmy Carr once, she says. "I'm not sure whether it was a rape joke or not, but I didn't like it. He does quite a lot of fat people jokes. A lot of the time, a comic's public persona is such a long way from their private persona. I think Jimmy's a nice guy; he seems like a perfectly reasonable person. But if you're doing a joke on stage you have to be prepared to support it and explain why you think it's all right rather than just chucking it out for the sake of shocking someone."
In May, Brand won a Bafta for her role in Getting On. Of course it meant a huge amount to her, but mainly because she had auditioned for drama school straight out of college, thinking it would be her path to stand-up comedy, "and the first audition was so humiliating I cancelled all the others".
A third series is on the way. What has always shone through Getting On is a deep love of the NHS. The changes to the health service will have to be addressed next time, I imagine. Brand, a lifelong Labour supporter – her parents met at the Young Socialists – nods. "At the moment they are pretending that nothing is going to happen, when how can it possibly not, particularly with the news that they're thinking of bringing in private companies to run hospitals, which I think will be a huge mistake. The next five years are going to be critical." She gives a weary smile. "If it disappears it will be an absolute travesty."
Jo Brand's Big Splash starts 22 September at 9pm on Dave.