Chris Hill doesn't eat bread, biscuits, crisps or chocolate. When he drinks alcohol, which is rarely, he orders vodka, lime and soda, never beer. Cakes and pastries are similarly avoided, as are pasta and cereal.
Instead, for breakfast, the 26-year-old procurement manager has a pork chop or piece of fish, usually salmon, with eggs and vegetables. Lunch is a chicken salad, and dinner is meat or fish with more vegetables.
Hill has been eating this way since April 2012, when he embarked on a low-carbohydrate diet to lose weight. Back then, he weighed 18 stone which, at 5ft 10in, gave him a body mass index (BMI) of 36.1 kg/m2, well past the obesity threshold of 30.
"I was self-conscious," he says now. "People would make remarks. If I went to the beach, I'd wear a vest."
His slimming regime of choice was the Paleo diet. Named after the pre-historic palaeolithic era, its premise is: if they didn't eat it 15,000 years ago, we shouldn't now. The reasoning – that our digestive systems haven't evolved as quickly as methods of food production – is secondary to the result, which involves a diet rich in meat, fish and eggs which promises to shed pounds, fast. Championed by the American nutritionist Dr Loren Cordain, it was Google's most searched-for diet of 2013.
Like many diets, its healthfulness is controversial; the British Diatetic Association warns that cutting out grains "raises the potential for nutritional deficiencies".
Nevertheless, it worked. Today, Hill is a muscular 12 stone and has a healthy BMI of 24.1. He still follows the diet – with the occasional treat – and works out at the gym, a mix of weight-lifting and rowing, for 45 minutes a day, four days a week.
"It has inspired me," he says. "At first it was strange, but I'm used to it now. I'm much fitter and happier."
According to the retail analyst Mintel, 29 million Brits tried to slim down last year. Some 66.6 per cent of men and 57.2 per cent of women are overweight. But if Hill is one in 29 million, he represents something else, too: the increasingly ubiquitous male weight-watcher. Slimming may never have been the exclusive preserve of women – Lord Byron practised the 'vinegar and water diet', consisting of water, apple-cider vinegar and little else, and Elvis would undergo sedation for days at a time to avoid eating – but it has long been our turf.
No longer. That same Mintel report found that 44 per cent of men tried to lose weight in 2013. That's up from 42 per cent the year before and 24.8 per cent 10 years ago.
Over coffee recently, a male pal regaled me with details of his strict 'no carbs' regime. He won't eat bread, potatoes or fruit. Another practically lives off low-calorie meal-replacement bars, bulk-bought from Boots and kept in his desk drawer at work. And then there's the manager I talk to who breakfasts each day on salad from Pret A Manger because "porridge is quite a lot of calories, really".
Where once weight loss might have been done on the sly for fear of appearing 'unmasculine', today male celebrities share diet tips in interviews. The actor Ryan Reynolds reportedly won't eat carbohydrates after 8pm. Hugh Grant has done the low-sugar 'Clean and Lean' diet. Benedict Cumberbatch follows the 5:2 plan – five days of eating whatever you want, two of eating fewer than 600 calories. Actually, everyone appears to have done the 5:2 – from George Osborne to Alex Salmond, Phillip Schofield to Jude Law. May this year saw the launch of Man v Fat, a new digital magazine aimed at men who want to lose weight.
What's going on? It has been more than five years since the Government's Change4Life campaign was launched, encouraging us all to make long-lasting changes to the way we eat. Is the public-health message finally getting through? Perhaps. But, as anyone who's found themselves weighing out portions two weeks before a beach holiday knows, dieting's often not about long-term health.
Women have long complained of the pressure they feel, subjected to relentless images of perfection by the media, advertising and entertainment industries. Now blokes appear to be feeling the heat. A recent survey claimed that 64 per cent of men felt ashamed of their stomach. More than half worry their friends have more appealing physiques. Did any man worry about his 'moobs' ('man boobs') until the term appeared in newspapers, circa 2006? Gossip websites revel in the imperfections of male stars. Actors Christian Bale, Colin Farrell and Leonardo DiCaprio are three whose supposed beer bellies have attracted attention recently.
Men's Health magazine – with its promises of "lean muscle fast" and "sculpted abs" – is the most successful paid-for men's magazine in the country. Every month, more than 210,000 copies fly off the shelves, each bearing a picture of a perfectly-chiselled cover star.
"It's always in your face," agrees Matthew Briggs. The 32-year-old from York weighed more than 31 stone when he joined a local branch of Slimming World. He now weighs around 16 stone. "There's that Bond film with Daniel Craig on the beach. You look at it and think, 'Well I don't look like that'."
Something else is changing, too: the diet industry. It is already worth a reported £2bn, and the male dieter presents a lucrative prospect. There are more overweight men than women in the UK; Public Health England predicts that by 2050, 60 per cent of men will be obese. Capture the market, and the profits could be huge.
And so, after decades of campaigns featuring women frolicking in swimsuits, the calorie-counting giants have upped their game. Weight Watchers is trialling a men-only diet group; it recently featured MasterChef judge Gregg Wallace as one of its 'celebrity ambassadors'. Slimming World runs eight men-only clubs.
But it's not just the traditional titans of weight-loss who've woken up to the business of shrinking men's waistlines. One of the most eye-catching trends in recent dieting history has been the explosion of new man-friendly regimes, which make money by selling books and branded products to those desperate to shed the pounds.
The apparent popularity of the 5:2 diet with men is, one recent devotee tells me, partly because it can be framed as a kind of extreme sport. "Another guy at work was doing it," says the fortysomething software manager. "We'd be like, 'How many calories have you had so far?' Is it macho? Yes."
Men's health consultant, Peter Baker, isn't surprised. "Men often need a different approach," he says. "Conventional 'dieting' tends to put them off. They prefer things framed as a challenge."
There's a similar machismo surrounding the low-carbohydrate Atkins regime, which eschews dainty low-fat nibbles in favour of meat, butter, cheese and mayonnaise. And then, of course, there's Paleo – the most self-consciously macho diet of them all, and not just because it's also known as the 'caveman diet'.
Like Hill, Martyn Rowe lost weight rapidly after "going Paleo" a year ago. In two months, the 42-year-old business manager had shed a stone and banished his "mid-life gut". Part of the diet's appeal was its focus on 'manly' food.
"If I turned up with a SlimFast shake, I would get the piss taken out of me. Now other guys see me eating steak and eggs and they're like, 'Hey, that's not bad'.''
Aiding the new breed of macho dieter in his quest to slim down is a growing range of macho diet snacks. Sales of diet food increased by 7 per cent between 2008 and 2013 to £1.8bn. PepsiCo and Coca-Cola have already launched Pepsi Max and Coke Zero to appeal to male consumers who felt Diet Pepsi and Diet Coke were too feminine. Now image-conscious male dieters can buy low-sugar Caveman Cookies, 65 calories each, Rebel Kitchen Mylk, flavoured imitation milk with approximately 50 calories per pack, and Thermo Detonator fat-burning supplements.
Online, dozens of web forums have been established by followers of these regimes. Patrick Vlaskovits, a 37-year-old Californian entrepreneur and author of several business books, set up the forum PaleoHacks in 2010 after a year on the diet. The site receives a million monthly visitors. Membership is free; revenue is generated by advertising.
This virtual community offers a support network male dieters might previously have lacked. Says Vlaskovits: "Members not only share worries and get their fears allayed, but also form real friendships".
Of course, there's comfort in community, but there's also a whiff of collective neurosis. Take this recent exchange, posted by one male member under the headline, 'Rooibos tea: Paleo or poison?'. The popular herbal tea, says the post's author, is rich in antioxidants and organic compounds. He worries that, as cavemen, we wouldn't have had access to sufficient vegetation to consume these.
More than a dozen co-dieters have responded, some giving the innocuous-seeming tea the thumbs up, others describing in alarming detail the "toxic" effects they believe it causes: fatigue, sleeplessness, anxiety. Their exchange looks at best a touch paranoid – at worst hysterical.
But then, that's the thing about dieting. It tends to come with a hefty portion of angst. "When I pick up something to eat, the first thing I look at is the information on the pack," says Ian Ward, who joined Weight Watchers five years ago, weighing 24 stone 7lbs.
The 47-year-old father of two from Derbyshire has lost almost 10 stone – but he will be counting calories for the rest of his life: "I've put back items because they've got 20 grams of fat".
Speaking at the parliamentary enquiry on body image in 2012, psychotherapist Susie Orbach, author of Fat is a Feminist Issue, described this as the lifelong straitjacket into which weight-loss programmes bind followers. Either you stick to the rules religiously, or you're left in a painful cycle of completing the diet, gaining weight, and starting all over again.
The flip-side to this growing weight-consciousness is that there will, inevitably, be those who care too much. Eating disorders among men are not a new thing – but they're increasingly common. University College London reported a 24 per cent rise in the number of men diagnosed with an eating disorder between 2000 and 2009.
Ravi Meah, a slight, 5ft 2in, 27-year-old production editor has spent a decade controlling his weight. He's tried meal-replacement shakes, calorie counting and the Atkins diet.
"The image of the ideal man – someone who has a V-shaped torso, six-pack stomach, and a chiselled jaw – has become so ingrained in our psyche that most men feel like complete failures if they don't look like it," he says.
The legacy of his obsession is a wildly distorted relationship with food: "Now I yo-yo. I go through two months when I don't go to the gym and eat all kinds of foods, then I work out intensively and go into Atkins mode." His weight fluctuates between eight and 10 stone – either at the low-end of the healthy BMI range, or just above it.
Ten years ago, the BBC ran a story in which various overweight men lamented the lack of diet options available. Slimming groups were too women-oriented, they said, and they felt inhibited by a prevailing social view that 'real men don't diet'. Rather like the ideas that 'real men' don't cry, do housework, or need parental leave, such notions are of course sexist rubbish which do no one any favours.
If men feel liberated to take an interest in weight management then that, surely, is a good thing. Another good thing is the promise of British men becoming leaner, fitter and healthier. Obesity-related conditions cost the NHS £5bn a year.
However, as Meah's experience shows, it's not always that simple. Because the fact is, men may have been getting fatter, without any recourse to do anything about it – but women have been getting fatter too, all while we've had diets coming out of our ears.
Repeated studies have shown that dieters are prone to regaining weight. And many women, of all sizes, live in a state of perpetual anxiety about their food consumption. Does the same fate await Britain's men?
Orbach, for one, believes so. "The results will be the same," she tells me. "Men induced into the bingeing and dieting pattern and disordered eating. The winners are the commercial companies."
Let's hope she's wrong. Perhaps men will fare better. Perhaps they will resist the pressure to strive for body perfection and fork out hundreds on dietary quick-fixes. Perhaps they will avoid the cycle of boom and bust that characterises so many women's relationship with the scale. But then again, perhaps not.
Sample menu: the paleo diet
Breakfast: scrambled eggs and bacon (no butter or oil).
Lunch: salmon and asparagus.
Dinner: chicken breast with broccoli.
Snacks: almond/pecan/walnut mix, or even some Paleo-approved fruit including apples, grapes, plums, strawberries, and mango
Sample menu: the 5:2 diet
On fasting days:
Breakfast: low-fat yogurt.
Lunch: mushrooms on wholemeal toast.
Dinner: 50g cooked prawns with roasted aubergine.
Snacks: half a grapefruit
Non-fasting days: whatever you like
Sample menu: the clean and lean diet
Breakfast: oatcakes spread with half an avocado.
Lunch: spinach and salmon omelette.
Dinner: lamb cutlets with sweet potatoes.
Snacks: a handful of nuts.
Research: Lily Rosengard
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