EDP column by Professor Ketan Dhatariya
“I’m nearly 70 years old and eat less and less at meal times. I do however seem to be developing a “beer belly” despite my weight being constant, what should I do?”
If you are a believer in evolution, read on. When human beings were evolving they were hunter-gatherers. They lived in times when they did not know when their next meal was coming. So when they did manage to kill an animal, they would need to eat the parts of the animal that were most calorie filled – the fat. We have evolved to find fatty foods more tasty for this very reason – something the fast food industry has been aware of for years.
When our ancestors ate more than they needed, they would have to store that extra energy in a form that was easy transported – that is, as fat. Fat has more calories per gram (9) than either protein (4) or carbohydrate (also 4). This fat would then be used as the energy the person would burn off between meals. If the next meal was a week away, that stored energy would keep them going. Now, however, there is a constant supply of food and we never need to go hungry, but we all eat a little more than we need. Evolution, has not caught up with our 24 hour food availability, and so if we eat more that we need, then we still store it as fat.
The question we must ask is why would we be allowed to develop a mechanism that allows us to lose energy? If food is very hard to come by (evolutionarily speaking) and we do not know when our next meal is coming, then why would we voluntarily want to lose energy? This is why weight loss is so very difficult. Evolution has not allowed us to develop any mechanisms to allow us to shed weight easily.
Weight gain, however, is very easy. The daily energy requirement for a man is 2,500 calories. Over a year, that is 912,500 calories. If he does eats 1% more than he needs (that is, about 1 mouthful extra per 5 meals), over the year, he may have eaten about 9,000 extra calories, and that means 1 Kg in weight (1Kg of fat is 9,000 calories). Or, if he does he eats the same amount as always, and does 1% less activity per year (maybe takes the lift once a day, and not the stairs), then he will not use that 9,000 calories per year, and that results in 1Kg weight gain.
The important thing is to eat healthily with sensible portion sizes, and do some regular exercise, such as building up to a 30 minute brisk walk every day.
As always, ask your doctor or pharmacist if this is safe for you and what they can do to help.