Yesterday's decree from the Secretary of State for Education unsettled me somewhat. On the face of it, teaching children the basics of how to cook is a laudable ambition. It does seem, on the face of it, that much of the current fatness epidemic is caused by poor eating habits. Children ape their parents so if they are fed a bad example there isn't much that is going to whip them into shape until they are mature enough to set their own direction.
I cannot be bothered to discuss this latest piece of NuLabour fatuity, so I wish to discourse upon the subject of fat instead.
The first point to note is that if you eat more calories than you burn, those unburned calories will be stored as fat.
This is because fat is more efficient at storing energy than sugars (which is why nuts are mostly composed of fat).
However, fats require additional processing before they can be used, and this processing, in turn, requires energy. Sugars require less processing and so will always be "burned" first. What this means is, if you are carrying a little extra weight, and then you have something to eat, then do some exercise, the calories from what you have just eaten will be burned first and not your stored fat.
Providing normal body function, you will always have enough sugar (specifically, glucose) in your bloodstream to deal with most normal exertions. If you do not, you will become hypoglycaemic and slip into a coma and die. If you have too much sugar, you will become hyperglycaemic and you will get very ill and eventually slip into a coma and die. Blood sugar is regulated by insulin, which is manufactured in a part of the pancreas known as the Islets of Langerhans: when, for whatever reason, human insulin production doesn't work properly, you end up with a condition called diabetes.
But I digress: given normal working, you will always have enough sugar in your bloodstream to deal with most normal exertions. So, what are the implications for weight loss?
The single most important thing to remember is that it is far easier to put on weight than it is to lose it.
The second important thing to remember is that it requires reasonably long periods of sustained aerobic exercise before you start burning your fat store.
The muscles store some fat globules in any case, ready for any aerobic exercise required.
Initially during aerobic exercise, glycogen is broken down to produce glucose, but in its absence, fat metabolism is initiated instead. The latter is a slow process, and is accompanied by a decline in performance level. The switch to fat as fuel is a major cause of what marathon runners call "hitting the wall".
In practice, it is a little more complicated than this, of course. However, the main point holds: you need to burn through your blood sugar before you start metabolising your stored fat.
So, putting fat on is an awful lot easier than taking it off, especially with our modern lifestyles.
The answer, as I have explained before, is not to eat so much.
If you are worried about becoming fat, maybe you should try your humble Devil's diet. I eat a large meal only every three to five days, and merely have a snack—bread and cheese, or maybe a couple of Gregg's steak bakes—at lunchtime on the other days. This is because I sit on my arse all day (occasionally twitching my mouse hand and typing this balderdash) and, working from home, I don't even walk to work anymore. You will find that you soon slip into the routine, and hunger doesn't strike (or if it does, porridge really hits the spot).
That was written about two years ago, when I lived in Edinburgh; my lifestyles is even more sedentary now due, perversely, to the fact that London is so much bigger: I tend to take public transport rather than walking everywhere. I have thus reduced my food intake slightly (though it's more regular).
So, there we are: lots of exercise and less food leads to less obesity. But the main point is to take the exercise before your food ends up being stored as fat, because it's a damn sight harder to get rid of than it is to put on.
Here endeth the lesson.