Unfortunate use of word
IT is indeed unfortunate that Dr Tim Noakes has used the word “genocidal” in relation to orthodox diets (“Noakes draws new fire with ‘genocide’ comment”, October 16). Strong language.
He undoubtedly knows more about physical exercise than I do, but I have taught human physiology – including nutrition – for most of my professional life and I therefore have some familiarity with the relevant literature – especially on nutrition, because that happens to be an interest of mine.
Fat is an excellent energy store. Weight for weight it represents about twice as much stored energy as carbohydrate.
This is why our bodies tend to store energy as fat rather than as “carb”.
More bang for your buck, so to speak.
But there are well-known reasons why “carb” (sugar), rather than fat, is the main minute-tominute energy currency. In the energy-releasing process, sugar releases more energy for each litre of oxygen used to burn it.
And oxygen, by the time it reaches our cells, is “expensive” stuff – rather like the price of petrol in Antarctica.
To base the energy content of a diet heavily on fat is to skew the normal order of things.
This indeed is why – as Noakes knows – a fat-rich diet is less fattening, joule for joule, than a carbohydrate-rich diet, and is popular with people trying to lose weight.
But a “maintenance diet” – designed to keep us in a stable state – should be based more heavily on carbohydrates (complex, fibre-rich sources, certainly) than on fats and oils (“lipids”).
Good diets of this carbohydrate-biased sort, eaten in non-fattening amounts, are neither time bombs nor genocidal.
We need to look to other aspects of our behaviour for these apocalyptic consequences of our stupidities.