Six months ago, Vijay Chawla weighed more than 27 stone. He was unable to walk up a flight of stairs, and his feet had swelled up from a size 9 to a size 11 simply from the pressure of supporting his weight. His waist measured 65 inches, and he had to have all his clothes specially made. In his desperation to lose weight, he resorted to surgery to reduce the size of his stomach.
Mr Chawla's story is one that has become all too familiar in Western countries grappling with the problem of obesity. But he is not a fast-food junkie from small-town America, or one of Britain's growing army of the overweight. Mr Chawla is from India, a country better known for images of stick-thin, undernourished children than it is for fat people.
But hidden among its starving millions, India has a serious and growing epidemic of obesity. The figures make alarming reading. A shocking 76 per cent of women in Delhi suffer from abdominal obesity. Even more disturbing is the rate of childhood obesity: almost 33 per cent of 15- to 17-year-olds in India's cities are now clinically overweight.
"It's a tsunami that is going to come upon us suddenly, after five to seven years, when these children grow up," says Dr Pradeep Chowbey, one of India's leading obesity surgeons. "Suddenly we'll find we have an adult obesity problem at Western levels."
Worse than that, Dr Chowbey fears that Indians may be at greater risk from obesity than Westerners - precisely because of their history of undernourishment. A current theory is that generations of hunger and deprivation have made Indians develop so-called "thrifty genes" that store more fat than those of people who have been well fed. The idea of a genetic propensity to gain weight is a theory that has not yet been conclusively proved, but it is one that has many adherents around the world, including in the US and Britain.
Dr Chowbey has a plastic model of a human stomach on his desk, complete with blood vessels, that opens up to show the interior. From his plush, air-conditioned offices in Delhi's Sir Ganga Ram hospital, he is one of a growing number of specialist surgeons answering the demand for stomach-reducing surgery in India. Already, hospitals are offering the operations in 15 different cities across India, from the major centres like Mumbai and Bangalore, to smaller places like Udaipur in Rajasthan.
All this is happening at a time when malnourishment is still very much a problem in India. Only two years ago, it emerged that several children had starved to death in villages in West Bengal state. More than 45 per cent of children in India are malnourished, according to the World Bank - a statistic that seems hard to reconcile with the rate of childhood obesity, until you realise that what it illustrates is the ever-widening gulf between the rich and the poor.
Childhood obesity is a problem of the cities, the business centres that have transformed India into the second fastest growing economy in the world. Most of the malnourished live in the villages, in the great hinterland of rural Indian that has been barely touched by economic growth.
In the West, we are used to thinking of obesity as a problem of the poor, but in India it is a disease of the rich. "The critical thing is that India is going be facing a double-edged problem," says Dr Chowbey. "We're going to have to deal with an epidemic of undernutrition and an epidemic of overnutrition at the same time."
Mr Chawla is a typical case. He lives in a plush apartment block in the modern Delhi suburb of Rohini, with uniformed guards at the gate. Inside, his apartment is floored with white marble. He lives a life of which his parents, ordinary Delhi traders, could not have dreamt. Mr Chawla founded his own company making television speaker parts. His success is a small part of the economic transformation taking place all over India.
It has thrown him into a lifestyle very different from his traditional upbringing. "My parents never touched alcohol," he says. "But until six months ago I used to have five or six drinks in an evening: wine, beer, whisky. My parents only ever ate traditional homecooked Indian food. But I used to eat a lot of junk food: pizza, chips, deep fried food."
Western-style fast food has become a fashion in India, which had few Western brands until recently. The likes of McDonald's and Pizza Hut are considered aspirational places to eat in India, crowded with rich young professionals who can afford to pay prices which are beyond the pockets of the poor. "When I was in my twenties the traditional belief in India was still that it was healthy to be fat," says Mr Chawla. A pot belly used to be considered a sign of prosperity in India. But in a society bombarded with the same images from Hollywood and American television as the rest of the world, those beliefs have died out, leaving people like Mr Chawla overweight and unenvied.
Dr Chowbey says there is more to the problem than a change in eating habits. "More and more evidence points to the existence of 'thrifty genes' in Indians and other populations who have been undernourished," he says. "These genes were originally helpful for survival and what they do is to convert eaten food into storage as fat. It starts with people who were undernourished or premature babies. Their children or descendants adapt by developing 'thrifty genes' to cope with undernourishment. But if that new generation has access to plenty of food they store too much fat. What this means is that countries where there were decades of undernourishment, like India, are facing a much bigger problem with obesity than other countries."
There are other factors in Indian society, however. For the wealthy in India, it is possible to take almost no exercise at all. It is not just, as is the case for Mr Chawla, that many are able to drive to work and park right outside the office. Many of the small everyday activities that force people in the West to take some exercise are taken care of by someone else in India.
Where the average Briton carries shopping bags on a fairly regular basis, the rich in India almost never do. Not only large supermarkets, but even the local grocery store, will take an order for shopping by telephone and deliver to your door. In fact, it is possible almost never to go shopping. Even furniture stores and jewellers will send a selection of merchandise for you to choose from in the comfort of your own home.
It all comes down to India's vast army of the poor - which means the country has a huge supply of cheap labour to draw upon. Domestic servants take care of almost every chore. Drivers mean parking is never a problem - giving rich Indians little incentive to walk to the metro station in summer temperatures that are regularly over 40C and humidity that soaks your shirt with sweat in minutes. Many wealthy Indians even get their domestic servants to walk the dog - giving up yet another chance of a bit of regular exercise.
Prateek Sawhney is another of Dr Chowbey's patients. A property developer, he lives in Delhi's upmarket Defence Colony, a neighbourhood known for its restaurants. He weighs over 21 stone, and is six feet tall. "The problem is lifestyle," he says. "I want to lose weight but I just don't do the things I'm supposed to.
"I eat out five or six days a week at very upmarket hotel restaurants, food with a lot of calories. What people don't realise about Indian food is that if you eat the traditional homecooked food, it's very healthy, but you don't get the same sort of food in restaurants. It was you British who started it: you added all sorts of cream to the traditional recipes, and it tastes great but it's not so healthy.
"I eat out because I'm socialising. You see, the thing is in the West you eat first, then you play. Here in India it's the other way round: we play first then we eat. We typically eat dinner at the end of an evening out, around midnight, then go home."
Obesity is causing other problems too. Like 33 million other Indians, Mr Sawhney suffers from diabetes, which he developed around eight years ago. India has the largest and fastest growing diabetic population in the world, and obesity is believed to be one of the major causes. The number of diabetes sufferers in India has grown tenfold since 1971.
The obesity epidemic is also leaving more and more Indians with heart problems, and other health disorders. Mr Chawla says that, at his heaviest, he began to suffer constant pains in his legs and feet from the pressure of supporting his weight. That was when he turned in desperation to Dr Chowbey for surgery.
"Once people reach a certain body mass index [the ratio of their weight to their height] they can't lose weight by dieting," says Dr Chowbey. "Their stomach has grown so much that if they reduce how much they eat their body will still feel hungry." Dr Chowbey ties a tight band around the stomach, effectively blocking off most of it so that food is only digested in a small part. It is an operation that is widely available in the West, but in India it is far cheaper. At first Mr Chawla approached a clinic in New York for the operation. He was told it would cost $12,500. That was when he turned to Dr Chowbey, who did the same operation for $3,000.
In the past six months, Mr Chawla has lost five stone. His blood pressure, which was dangerously high, has reduced to healthier levels. He used to take the lift from his apartment to the ground floor. Today he walks down the three flights of stairs.