A Calorie is a Calorie by Keith Frayn: The real reason you can’t lose weight – and no,
A Calorie Is A Calorie by Keith Frayn (Piatkus £16.99, 320pp)
It’s back-to-basics time when it comes to controlling our body weight. So says Keith Frayn, Emeritus Professor of Metabolism at Oxford University, in his scientific and persuasive book on the subject.
Ditch wishful thinking, such as that intermittent fasting ‘speeds up the metabolism’, or that different foods have different metabolic effects. The truth is that ‘there are no tricks. Our body weight trajectory is determined by the balance between calories in, calories out.’
The beauty of believing that a ‘calorie is a calorie’ is that there are no foods you can’t eat. You don’t have to give up bread, butter or wine – but you do need to keep a careful count of energy in and energy out.
I thought of my daily addictions (biscuits with the cup of tea, salted nuts with the glass of wine, chocolate after supper) and felt ‘seen’ – especially when Frayn reminds us that one mile of jogging uses up a mere 100 calories (not that I even jog; I just walk the dog).
A slim man himself, Frayn is asked by lots of envious fatter people, ‘Why is my metabolism so slow?’ Those who find it hard to lose weight often cling to this excuse for why it isn’t happening.
Really, they’re just consuming too many calories and not expending enough. Frayn approves of the T-shirt that says ‘I run so I can eat cake.’ If you don’t run, don’t eat cake.
Which to blame most? Gluttony or sloth? It’s both. And don’t fool yourself that different kinds of fats are treated differently by the body. ‘There’s one system, one final common pathway, by which we derive energy from all our fuels. Metabolically, the different fuels are handled identically.’ Yes, extra virgin olive oil is healthier than polyunsaturated fat, but no less fattening.
He acknowledges that it’s not easy to stay slim. Food accosts us wherever we go. And our genes, since hunter-gatherer days, have been shaped to gorge when we can, building up our stores, so ‘when we wish to lose some of those stores, we are fighting against responses honed over millions of years.’ The good news is that ‘when famine comes, those with extra weight will be laughing at the skinny ones’.
Cut them out: If you want to lose weight just reduce your calories
Frayn sometimes bamboozles the reader with scientific data – ‘linoleic acid has 18 carbon atoms and two double bonds’ – but he has a duty to back up his theory with proper science, especially when trying to hold his own among nutritionists pumping out books about the metabolic benefits of intermittent fasting.
He steps down from his high professorial tone to tell us that he does have marmalade on toast with no butter, as he abides by his mother’s saying: ‘It’s not worth the calories.’ (For me butter is worth the calories.) He says that if you walk 12 miles a week, you’ll burn off 1,200 calories.
By such methods, plus cycling around Oxford and walking up escalators, he burns off 71,000 calories over a year, ‘producing the same effect on calorie balance as going for a month without food’.
Now, that makes losing a bit of weight suddenly seem less daunting. If only I could give up those salted nuts…