12/08/2013 20:25 BST | Updated 12/10/2013 06:12 BST

India's Supersize Kids

India is a food nation; the one thing you don't deny people is food. My mum taught me, if someone comes to your house you always offer them something to eat. Traditional Indian food is full of vegetables, lentils, rice, wholemeal bread; recipes taught and passed down from generation to generation, but it's hardly a high fat diet. So how was I now back in India to make to make a programme for the BBC about the emerging crisis of obesity, or 'dia-besity' that's unfolding there?

I arrive to start filming in Mumbai, during Diwali, the festival of light. I am gobsmacked by what I find; the family of a seven year-old child who has had serious gastric surgery to save his life after tipping the scales at 14 stone. His mother admits that traditionally it is felt that a chubby kid is desired, it's a sign of being healthy, and wealthy and she never restricted what he ate.

If you have a fat child in India you don't talk about the issues surrounding the fact you have an obese child it's just you have a fat child - perhaps fair enough in a country that for so long has largely fought hunger. But it seemed that Indian kids are now catching up with western society and the problem is that they want more want pizzas, fillets o' fish, fries and burgers, anything that's not curry.

It was in the 1990s that the Indian economy opened up and fast food flooded in - KFC was the first to arrive and this new generation that grew up with the internet, watching Friends, Hollywood movies as well as Bollywood movies, and embraced the Americanisation. Sitting in an air conditioned, branded restaurants offered a slice of western life. I remember visiting Calcutta in 2006 and McDonalds had just opened. On a Sunday night there was a massive queue outside; emergent, middle class families wanting to come and experience the bright lights and burgers that the west has had for 30 years.

But as the country's economy grows the national waistline has swelled too. And it's the children that are feeling it most. In a country that is traditionally viewed as skinny I was astonished to meet a 13 year-old who weighs a staggering 17 stone. His story was chillingly similar to the issues facing kids in the west today - the bullying and the social isolation that sometimes goes with being young and overweight,

It seems that while we have strict regulations in the UK; an advertising standards agency, a food standards agency, in India there's few regulations that ensure companies make their consumers aware of the content of their food. I saw fast food adverts that looked as if they were targeted at children, junk food sold right next to schools - all the stuff we've cracked down on because we know what it's doing to our children. But in India there just doesn't seem to be the western awareness about how detrimental it is to your health to be fat. I meet middle class mothers, maids, sisters, grandmothers all feeding these kids as no-one wants to deny them.

And genetics adds an extra complication. There is a theory - the Thrifty Gene Theory - that Asian civilisations have genetically adapted to be able to store fat in times of famine. Now with increasing fatty diets, all this excess is stored around the waist and it means as a nation Indians are pre-disposed to getting diabetes. One surgeon I meet says: "It's genetics that load the gun and the environment that pulls the trigger."

Yes, a surgeon, because of course alongside this crisis there is a growing trade in weight-loss surgery. The 13-year-old I mentioned earlier - had a gastric band fitted as his mother feared it was the only option available to help him lose weight. But it's an option only able to be afforded by a few.

There is still a huge divide between rich and poor, the people who have, have and they can afford a great life. You don't have to earn a vast amount of money to have a maid, driver, be able to eat out three times a week in India, you don't. They're not the uber-rich but the middle class. But then there are the people that have nothing, really have nothing. Two thirds of the population survive on less than £2 a day and malnourishment is an on-going issue that needs money and attention.

Here's where the government is going to have to step up. But it's a hard task. Are they going to provide for the poor, feed the masses, which absolutely must be a priority, or try to equip their healthcare system so it can cope with all the problems that come with having an obese nation, one with heart issues, hypertension and high blood pressure. Medical professionals are bracing themselves for a massive diabetes surge in the next twenty years and estimate the number of sufferers will reach the 100million mark, so unless India addresses it's attitude towards food, the 13 year-olds having gastric bands fitted could just be the tip of the iceberg.

This World - India's Supersize Kids - BBC Two

13 August, 21.00