Most mammals will put on some extra weight to tide them through the ‘harsh’ winter months when food is hard to come by. Some will hibernate and all will emerge thinner and ready to rumble once the winter is over. Perhaps even humans did that before civilisation raised its ugly head. Today, civilised humans are probably the only ‘animals’ that eat more than they need to and never work the excess off.

Before the advent of civilisation the life of a human was very simple. You were hiding from something, running from something or running after something. All that kept you fit and hungry but did not allow time for poetry, art or long lives. And no cooked food until Prometheus gave humanity fire and suffered grievously for it.

Then came civilisation. It started slowly. First came domestic animals and herding, and then came farming and production of grain and soon thereafter the production of beer. With beer came stargazing and that probably started astrology and perhaps a few of the ‘finer arts’.

And so civilisation was on a roll. Soon we have cities and armies and people now run from or after each other. But we also have peace. And with peace came a middle class. That gave us ethics and morality and religion. Why the middle class? The poor have no time for morality and the rich have no need for it.

Now people start living together in towns and cities. That means they started passing on infections to each other and with a little bit of travel we get famous epidemics like the ‘Black Death’ that virtually wiped out civilisation in the Muslim heartland (circa 1350 AC). And it allowed Europe to emerge from its dark ages.

What people ate got more civilised also. Spices! Journeys of discovery! Colonialism! New worlds! Slavery and yes, good food. But it would take time before food overwhelmed humanity. Until the beginning of the twentieth century people still walked and climbed stairs and perhaps even rode horses and much farming and manufacture still involved extensive physical activity.

Then came the internal combustion engine and suddenly in two generations the amount of normal physical activity diminished rapidly. But what we ate remained the same or as people got richer, even the food got richer.

For the first half of the twentieth century, two world wars and a major economic depression in the middle kept things nutritionally depleted. But after the nineteen fifties, there has been relative peace. There were and still are regional conflicts and regional famines, but no paroxysm to match the ‘War’ to end all wars.

Most importantly medicine advanced enough to conquer major killers like tuberculosis (TB) and small pox. As a result of that and general understanding of ‘micronutrients’ like Vitamins and Iodine in diet, life expectancies almost doubled in many ‘civilised’ countries and got much better in countries like ours.

As the world settles into a state of relative peace and plenty, we have a new set of the ‘Four Horsemen of the Apocalypse’. Instead of war, famine, pestilence and death, we have obesity, heart disease, diabetes and cancer. And all of these eventually lead to death and they are also related to each other.

Frankly whether we like it or not, we all will die someday. However obesity is one disease if I may call it that which literally, and here I do mean literally makes our lives miserable.

If you run ten miles a day then as long as you eat enough including a little bit of everything, how much you eat does not matter. But if you do not, eating more than what your body needs will make you fat and that will bring other problems with it.

In the modern age of ‘political correctness’ (PC) words like fat are no longer acceptable. So as physicians we now depend on measurements like the Body-Mass-Index (BMI). A BMI of between eighteen and twenty is normal and as you go near thirty and go above, you are getting into obese (really fat) territory.

Today I am not going to address the problem of obesity as such but rather of the few kilos we put on during the ‘wedding season’ or the ‘holiday season’ that might force us to invest in an entirely new wardrobe after the new year and for men in this part of the world to switch to ‘kurta-shalwars’.

Prevention as they say is the best treatment. Here the latest food research has brought some new insight. The classical point of view was that weight gain is all about calories consumed and calories burnt. The source of calories did not matter.

Before I go further I might wish to go back in time a bit. Some sixty years ago when I was still a young one, my elders would often get together and since many of them were doctors, the question of the perfect diet was often brought up.

From my memory of those discussions it seemed that the diet eaten by the pre-civilised’ humans was thought to be the best. That diet was based on fruits, nuts, some vegetables, and animal products including milk. Carbohydrates were not thought to be the ideal basis of a human diet.

Interestingly many of the ‘modern’ diets designed to lose weight do harken back to what my late uncle, a graduate of King Edward Medical College, 1930 would have read about today and said, I told you so.

Some general idea about different food groups is worth a mention. Fat carries important fat soluble vitamins and is easily stored for use during ‘lean’ times. Proteins from animal sources are needed to build muscle and other body parts. Vegetables provide water soluble vitamins, micronutrients that come after much washing with microscopic particles of dirt and of course fibre that keeps our guts moving.

Carbohydrates come in two general forms. Grains (starches) and sweet tasting fruits. And fruits are definitely a better form of carbohydrates since they also provide some of the benefits of vegetables. Carbohydrates are basic providers of energy. People that perform daily major physical exertion need a lot of carbohydrates but the rest of can do with a lot less.

So what was the new insight I mentioned above? Based on the latest nutritional research, all calories are not the same. Carbohydrate calories are worse for weight gain than other forms of calories that we consume. Or to put it in a different way, eating fewer carbohydrates especially as starch will facilitate a weight loss plan.

Over the next few weeks if your trouser belts or fitted dresses start becoming a bit tight, lay off the cakes, the biryanees and the roghni naans, and stick to karahi gosht and the milk protein and egg based deserts like the kalakand, barfee and my favourite, the egg custard.

The author served as professor and chairman, department of cardiac surgery, King Edward Medical University.