The obesity crisis is becoming yet another defining problem of our society, however unlike global warming and the AIDS epidemic, researchers and politicians are in this instance largely focused on saving the nation's children- presumably they assume its too late for the rest of us. It must be admitted, they do have a point- after all ,if Whitney Houston is to be believed, 'the children are our future'- and no-one really wants the human race of the future to be spherical balls of adipose tissue rather than super-intelligent cybernetic hybrids, do they?
Increasingly research into the 'obesity epidemic' is turning up more and more genetic components to weight gain, however it is important to note (because a failure to do so would be to enrage geneticists everywhere) that most of these 'fat' genes are not little switches: they might increase your risk of obesity or diabetes but your lifestyle is still the main causative factor (many loci influencing such traits account for less than 1% of variation).
One of the more interesting areas of this research is investigating the importance of eating rate in weight gain and the degree to which it is heritable. It is generally accepted that there is a positive correlation between eating rate and the amount of food consumed- a statement that led to my grandmother winning a long-term argument to the effect that eating slowly would make me lose weight- it seems, frustratingly, that once again she was right.
One study by Llewellyn et al. published in 2008, examined this correlation by filming 254 pairs of twins aged 10-12 eating a normal meal at home, then analysing the footage to identify eating rate and quantity eaten. The children were classed as obese, overweight, higher normal weight and lower normal weight and all were given more food than they could eat.
The results showed that the more overweight the child was, the faster they ate and, in addition, that the lower normal weight group ate significantly less than the obese or overweight groups. They also found a higher correlation of eating rate in eating rate between identical twins than there were between non-identical (fraternal) twins- results consistent with strong evidence for a genetic component.
Despite this evidence of heritability however, the study urged that early promotion of slower eating for children could lower the mean population weight and help control obesity, even citing a study in which it was found that simply encouraging children to put their knife and fork down between bites succeeded in both slowing eating rate and reducing the amount of food eaten over a six month period.
So for once it seems the older generation has the right of it: sitting down to dinner at the table and not bolting your food can benefit families- not because their children will become better mannered but because they'll significantly reduce their food bill.
So have geneticists unwittingly found a diet that works? I say its worth a try- after all its got to be better than eating half a grapefruit
http://www.ajcn.org/cgi/content/abstract/88/6/1560
Granny is always right... alas.
ReplyDeleteWhen I lost weight back in my late teens, eating more slowly was definitely part of it. Also, some things which you pretty much have to eat slowly (like fruit, salads etc) are pretty low-calorie. Foods which are easy to scoff fast tend to be, alas, not high in good things like fibre.
I was quite a slow eater as a kid, and remember a couple of occasions when I didn't have time to finish lunch at school before being herded back to a classroom... so I wonder if part of the problem is kids learning to scoff their food in order to go out and play/go to registration/etc?