Katie Hopkins is over the moon that she has managed to drop from a size 18 to a size 8 in just a few months - but her husband will be equally chuffed with his new slimline wife.

Because the star has revealed that she banned her partner from sex after piling on the pounds as an experiment for a new television show, which airs on Friday.

Katie went from 8st 12lb to 11st 13lb and then lost the weight again to prove how easy it is to get fit.

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Katie Hopkins gained three stone, then lost the weight for a new TV show. She originally weighed 8st 12lb (right) but ate her way to 11st 13lb (left), then dropped back down again in just a few months to prove how easy it is to lose the flab

But in her heavier months, the 39-year-old refused to make love to her husband Mark Cross because she believes fat people aren't sexy.

She told The Sun: 'After I put on my first stone, I stopped having sex with my husband.

'As a fat bird, I stuck to my pyjamas and getting naked in the dark.

'A fat belly is not an attractive thing, fat people aren't sexy.'

Katie caused an uproar last year, when she told an obese woman on This Morning that she wouldn't employ her because fat people give off the impression that they are lazy.

But she decided to put her money where her mouth is with her latest project, by gaining and losing 3st for a documentary to prove that overweight people are unwilling - rather than unable - to lose weight.

The weight gain hit Katie's emotions harder than she expected, with the mother-of-three often reduced to tears over her size, especially when she caught sight of herself in the mirror.

The documentary 'Katie Hopkins: My Fat Story' follows Katie Hopkins as she gains 3st on a mammoth diet of 6,500 calories a day, then loses the weight through a healthy eating plan and exercise

Katie told the newspaper that she hadn't cried for years, either at the birth of her children or her two weddings, but that gaining 3st 'killed her' and she often sobbed at how unhealthy she felt during this project.

Previously a slim size eight, weighing in at 8st 12lb at 5ft 7in, the 39-year-old gained nearly 3st by gorging on 6,500 calories a day and severely limiting her movement.

With an apparently naturally high metabolism, Katie struggles to bring her weight up over 11st despite her high-calorie intake.

The documentary sees her draft in ex-army personal trainer Christian who devises a military style program of what he terms 'circuit eating' to help her gain the final pounds.

Diving a table into four, Christian places different foods in each section and makes Katie rotate the table six times, eating the small but high calorie foods at each point.

Similar in form to exercise circuits, the idea is to maximize calorie intake, and the circuits have to be repeated every two hours.

Katie Hopkins refused to be intimate with husband Mark Cross, pictured, after she gained a stone in weight

After one particular feed, clearly uncomfortable with a distended stomach, Katie rants: 'It is just ridiculous what people do to themselves. Fat people, I mean really I don't know how they look at themselves in the mirror.'

Having reached 11st 13lb, with a 38in waist and a BMI of 26, the documentary Katie Hopkins: My Fat Story, which is due to air on TLC this Friday and Saturday, then follows Katie as she loses the weight on a strict diet and exercise regime.

In the TLC documentary, we see the usually polished star in her unguarded moments.

Make-up free and in a pair of stripped pyjamas, Hopkins breaks down over her larger body.

After a weight-gain diet that included daily 'snacks' of a litre-and-a-half of Mars milk drink, an entire tub of Pringles, cheese on toast, Dairy Milk and Galaxy chocolate and the inclusion of a second breakfast, Katie then cuts her calories to a mere 1,500.

As well as a low fat diet of porridge, salads and lean chicken with a jacket potato, Hopkins upped her daily steps from 1,000 to 20,000 daily and introduced several hour-long runs a week.

Following this self-devised plan she managed to drop down to 9st 12lb in just three months, shedding a further 6lb after the documentary ended.

The controversial figure claims that while she didn't shed a tear at her wedding or the birth of her children, gaining 3st 'killed her' and left her in constant floods

Katie kept a video diary during the making of the programme and regularly recorded her strong views on fat people.

One video sees her explaining: 'One of the things about being fat and eating all the time is you find you don't want to go out so much. You feel like you don't really want to go out because you can't fit into the things you would like to wear.

'I'm not sure if that's something many fat people suffer from because I see a lot of fat people out and about. Whether that's out of choice I don't know but I'm surprised that fat people go out at all.'

The former Apprentice contestant, turned columnist said in the Sun: 'I think I have proved there are no excuses to be overweight, but I've also shown that it affects you more than physically.

'I still wouldn't employ a fat person after living a fat life.

'Being fat is hard work. You can't be fat and happy. If you're too lazy to make a change then you're going to be fat.'

But despite the hardships that she suffered after gaining weight, Katie maintains that she still wouldn't employ a fat person.

She also suggested a radical weight-loss scheme in her interview with The Sun, which would see children weighed at the school gates.

The fattest 10 per cent of children would then be reported to social services.

The controversial former reality star has been as active as usual on Twitter, defending her views on being overweight

Katie first embarked on the weight-gain and weight-loss scheme after becoming sick of hearing excuses thrown around by overweight people for their size.

Speaking on ITV's This Morning in September she said: 'One in ten of our children are starting school overweight or obese and one in three children who are 15 or over are overweight or obese.

'People have always said to me, "You're lucky, you're skinny," and I just don't think these excuses are cutting it any more.

'I saw a story the other day about how the curtains in your bedroom not being thick enough could be making you fat. I just thought, we have to put an end to this.'

While she now has greater sympathy for people with weight issues, Katie is continuing to be outspoken on the topics, using her Twitter account to make digs at larger people in her neighbourhood.

She recently tweeted: 'My local over/under active thyroid self help group meets in KFC.'

She also posted: 'I see you all down there with your excuses, but a third of the planet is obese. The first step to slim is NO EXCUSES. Own your problem.'