He writes about health topics, and food - and occasionally ventures into the subject of obesity.
Well, his latest thinking - after talking to experts and boning up on all the latest research across the world - is that if you get fat, you might as well resign yourself to never being slim, long-term, again.
His main findings, summarised, are that:
- A) our bodies are programmed to go into fat-storing mode if we diet, doing so by lowering our metabolic rate.
- B) after losing weight by dieting, our brains are less able to exercise willpower around food, and
- C) it's more or less a waste of time trying to lose weight once you've put it on.
Depressing, or what?
C) struck me as such a momentous conclusion that I went back and read the piece twice more, very slowly.
In fact, most of what he reports is stuff I already knew. As long ago as 2002 when I wrote the first edition of The Diet Bible (an unbiased look at weight control), I reported that dieting slows down the metabolic rate. One of the main reasons, not mentioned by John, is that you weigh less - your body has less work to do so you burn fewer calories. So at 10 stone you won't be able to eat what you did at 14 stone and maintain your lost weight. And as I said last week, once you come off a restrictive diet, you'll always be tempted to go mad around food. We've always known all this, but now we know a lot more about the reasons.
But I wish Naish's conclusion had not been quite so doom-laden. He mentioned not a word about the fact that well-respected sports and nutrition scientists have found that people who take regular exercise are those most likely to keep lost weight off. It would also have been good to mention that now we DO know a lot more about the mechanisms behind putting the weight back on it should surely be only a matter of time before the scientists come up with the answers.
Meanwhile - as John says, the only failsafe thing is to make quite sure you don't get overweight in the first place. In our world, that's no easy option, though.
I shall continue to have faith in dieting - if it's the right kind of dieting: doing it slowly, being kind to yourself and taking lots of activity. Now I'm off to the hills, rain or no rain. I intend to defy the statistics - and never ever see 12 stone again.
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