I knew what I was buying. When we met in 1998, my husband Kevin's nickname was Starchie - not only because a friend of his decided he had a head shaped like a King Edward potato but because, given any choice in food, he always picked the stodgiest option.
In the early days of our courtship, I remember him complaining that potato on pizza wasn't easy to find, saying dreamily what an ideal pairing it would make. Thankfully, he had chip butties to fulfil his carb-on-carb needs.
At the time, I didn't even know what a chip butty was. I had grown up in Australia to Greek and Egyptian parents, eating a largely Mediterranean diet of rainbow-coloured vegetables, lamb or fish with rice and lemon and oregano.
From fit to fry-up
I was 28 when we met, and had bought into the whole aerobics and rye bread thing (it was the nineties) and was a fully paid-up member of the health-junkie club, walking an hour before work every morning and hitting the gym three times a week. I'd even dated a personal trainer.
Back then – and still today – people comment on what an odd couple we make: the hedonistic, pizza-loving man and his gym and alfalfa-sprout obsessed wife. Little and large probably describes it. I was a slim size 10 and he was, well, "Find as many XXXs before the L and buy that," was the way he described his shirt size when I asked.
But before long I'd caught Kevin's eating choices. Once married, we moved to Ireland for his work and he and his family introduced me to my first fry-up, at his Aunt Phyllis's house, featuring lashings of bacon, sausages, fried bread, black and white pudding and potato farls (bread – yes, bread – made of potatoes, then fried in bacon fat). I was hooked. Then there was the Guinness – the most sensual, luscious liquid that had ever passed my lips.
I became addicted to junk-carbs, swapping my single rye and avocado on toast breakfasts with Kevin's choice of six (yes, six) slices of Irish batch bread – more like cake than bread – with lashings of butter and jam. And it showed. In those first six months of marriage I went from just over eight stone (50 kilograms) to nearly 10 stone (I'm 5ft 4in), barely noticing that I was perma-clad in elasticated tracksuit bottoms.
In the jeans
My experience was in keeping with new research suggesting that your partner has a far greater influence on your weight than your parents. Researchers analysed 20,000 people from Scottish families, with an average age of 55, and compared their family's genetics and home environments, both in childhood and adulthood, to body fat content and body mass index.
"We wanted to know what the causes of variation on weight were in our population," says Professor Chris Haley of the Medical Research Council's Human Genetics Unit at the University of Edinburgh. "What we found was that thinner people tend to be married to thinner people and fatter people to fatter people."
This is explained in part by what scientists call "positive assortative mating; that like attracts like". But the study suggested that habits were more important. Having a partner with healthy diet and exercise habits decreases your own risk of being obese, whereas having an obese one does the opposite. Haley concluded: "Who you're married to is the biggest environmental influence on whether you will be fat or thin."
In my case, so it proved: I had jumped into my husband's lifestyle and was now carrying the flab to prove it.
The uncomfortable truth
Felicity Lyons, registered dietitian and spokesperson for the British Dietetic Association, is unsurprised. "When you're looking for someone, you make huge efforts to look after yourself, to be attractive, and then when you find someone and marry them, you get comfortable," she says. "In my experience, it's much more common for the woman to gain weight because she's more likely to take on the serving sizes of the man than the other way around."
On Christmas morning 2001, a friend took a picture of me sitting by the fireplace in my regulation tracksuit bottoms, sandals and socks. I looked like I'd swallowed the size 8 self I'd left in Australia. I realised I had to divorce – if not my husband, then certainly myself from his diet. I began running daily, doing a lot of yoga and swapping my batch toast for porridge. By the following year I had slimmed back down to my fighting weight.
My healthy habits didn't rub off on him, however. Even when we moved to London and I became a health director on a national magazine, Kevin was unwavering in his commitment to pizza and beer. One morning, standing in front of a mirror in his pants, he turned to the side, clutched his belly and remarked: "A lot of men have my body shape – executive."
Making a change
When he did finally make a change, five years ago, it was nothing to do with me, but the £450 ($875) he'd paid a Harley Street specialist to find out what was causing his coughing at night. He emerged with the clinical diagnosis, "You're fat", and the prescription, "Lose weight". The doctor's advice was to cut all carbs: "Anything you enjoy? Stop eating it," were his exact words.
With evangelical fervour, Kevin went cold turkey, giving up all alcohol, pizza – even potatoes – and began a regime of protein shakes for breakfast, chicken salads at lunch and meat and vegetables for dinner. He lost weight quickly, going from 16 stone to just over 14 stone in 12 weeks. Though his weight has since crept back up just over 15 stone, there are now only two XXs required before the L when I'm shirt-buying.
In April last year, I went vegan as an experiment for a story in this newspaper. Though I expected to end it anaemic and knackered, I emerged 60 days later, leaner and more energetic. A stone lighter, too. Did Kevin join me? Not a chance. He declared that if I was trying out veganism, he was trying out pizza-ism, adopting a slightly pared-down version of his pre-medical "see-carb, eat-carb" regime.
I'd be lying if I said I didn't worry about Kevin, but his cholesterol is better than mine and his blood sugar and blood pressure are normal (he never did go back to the beer, which might have something to do with it).
It seems Professor Haley's theory holds: having each swung to one end of the healthy-eating extreme, then the other, we've now reached an equilibrium that has left us both a bit thinner than where we started.
Our little-and-larger pairing somehow works for us, give or take a spot of tofu.
The Telegraph, London