What makes us fat? Is it an unhealthy diet, a lack of exercise, a bit of both or something else altogether? Most of us believe that it must be one of the former three reasons. But I was rather alarmed to discover that being overweight - indeed, even obese - can be, in fact, hereditary as well.

There is more alarming news yet to come. Over the past few years, trends in gauging one's level of fitness have come to involve calculating one's BMI (Body Mass Index), which is our weight compared to our squared height. Historically accepted norms have indicated a BMI between 18.5 and 25 (kg/m2) to be normal. Anything between 25 and 30 is considered overweight; if you fall above 30, you are obese and the absolute red zone, morbidly obese, is 40+.

Now here is the bad news; while the world was happily measuring its health levels and fixing things according to these BMI standards, Asians were facing a rather bizarre dilemma altogether. In fact, a series of independent surveys carried out in 10 different Asian countries have revealed that Asians falling well within the “safe” BMI range are suffering from classic symptoms of obesity diseases such as hypertension. What's more — even though Asians do not look apparently fat, they have more body fat content compared to Caucasians!

In other words, an Asian and a Caucasian may have the same height and weight, but the Asian will have a higher level of body fat and hence a greater vulnerability to obesity-related diseases at a much lower BMI than the Caucasian. This profoundly serious discovery compelled the World Health Organisation to reveal a different set of BMI standards for people of Asian origins. And so apparently for us, 23 is the magic number. Anything above that is overweight and a potential health risk.

One theory behind the cause of this difference between the races — cited by Jeffrey Friedman, a researcher in a New York university — is rather fascinating and plausible as well. According to Friedman, populations that store more body fat may have been naturally selected to do so over generations of famine. Simply put, centuries ago, people in areas prone to famine — such as China or India — developed a biological mechanism to store more fat to survive. When subsequent generations prospered, they accumulated excess fat and hence the higher levels of body fat.

However, Asians are not the only ones who have something to worry about. Official figures released by the British government state that at present, one in four men and one in three women in the UK are overweight. One in three children between the ages of two and 15 are overweight. The future appears to be rather grim as well; the Department of Health has predicted that by the year 2010, 6.6 million men and 6 million women in England will be obese.

With statistics so grim, there is little wonder that the British government is trying to instil a greater sense of responsibility among people regarding their body weight. Naturally, the media and the fitness industries are cashing off this massive potluck in every way possible with TV shows like X-weighted, The Biggest Loser, You Are What You Eat, Paul McKenna Can Make You Thin, Family Fat Surgeons et al doing the rounds nearly everyday. But amidst all this ranting, there are important lessons to be learnt for Asians as well.

We cannot deny the fact that being overweight is bad news; being obese is even worse. Excess weight can lead to several health problems like hypertension, heart disease, balancing and bone problems, low self-esteem as well as abnormal hormonal changes among a myriad of others.

And as with any other health complication, here too, prevention is better than cure. Health authorities recommend we indulge in at least 30 minutes of exercise of moderate intensity for at least five days a week to stay fit. Moderate intensity means any activity that leaves you feeling mildly breathless; you should be able to talk but not sing during the exercise. Brisk walking is an ideal activity that a broad spectrum of people can perform without much difficulty most days of the week. Moreover, the 30 minutes does not have to be at a stretch; you could do three bursts of 10-minute activities through the length of the day. On top of this, muscle-strengthening activities are recommended two days in the week for significant health benefits.

Unfortunately in the East, there is little trend of indulging in activities involving improving one's physical fitness. A handful of the privileged few city dwellers may have caught on to the trend, but it still largely remains more of a fashion statement for the affluent, limited to the extent of being seen in and around popular health clubs on the other side of the bridge in Karachi. In fact, if a person is thin enough, it is not deemed necessary for him/her to indulge in any exercise whatsoever.

But according to the WHO, “Health is a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity.” When we go beyond our skins hence, our body chemistries will tell a different story altogether.