Genes not poor diet blamed for most cases of childhood obesity

[Sash]

Nature, and not nurture, is the chief reason why some children put on weight while others stay slim, according to research that suggests parents are not entirely to blame for the epidemic of childhood obesity.

British scientists have found that genes account for more than three quarters of the differences between children’s waistlines, with lifestyle factors such as diet and exercise playing a much smaller role.

The results, from a study of 5,092 pairs of twins aged between 8 and 11, indicate that different family environments explain only a little of the variation in obesity between today’s children. Those who get fat tend to do so because they have a genetic predisposition towards obesity.

It raises questions about the recent decision by Alan Johnson, the Health Secretary, to notify the parents of five-year-olds who are found to be obese. Such children are more likely to be putting on weight because of their genes than any influence their family and home environment has had on their lifestyle.

“This study shows that it is wrong to place all the blame for a child’s excessive weight gain on the parents,” Professor Jane Wardle, of University College London, who led the research, said. The findings, however, do not mean that environmental factors play no part in obesity. Despite the strong influence of susceptibility genes, their prevalence has not altered in recent decades and it is environmental change that has driven the rise in childhood obesity across the population.

What studies of lifestyle have failed to explain are the differences in individual children’s responses to their “obesogenic environment” — factors in the environment that encourage sedentary behaviour and overeating.

In the study, which is published in the American Journal of Clinical Nutrition, Professor Wardle and Susan Carnell looked at Body Mass Index (BMI) and waist circumference in pairs of twins.

As identical twins share all of their genes while fraternal twins share only half, and they share broadly similar environments, comparisons between twins who live together or grew up in the same families can tease out the relative contributions of nature and nurture.

The results, showed that identical twins were considerably more likely than fraternal twins to have similar patterns of obesity. For both BMI and waist circumference, genes accounted for about 77 per cent of the variation between individuals, and environmental factors for 23 per cent.

“We looked at identical pairs of twins who share all their genes and compared their measurements with non-identical pairs of twins who only share half their genes,” Professor Wardle said.

“Contrary to the widespread assumption that family environment is the key factor in determining weight gain, we found that this was not the case.

“These results do not mean that a child with a high complement of ‘susceptibility genes’ will inevitably become overweight, but that their genetic endowment gives them a stronger predisposition [to being overweight].

“In today’s environment — which provides unprecedented opportunities for all children to overeat and be sedentary — it is not surprising that these tendencies result in weight gain.”

BMI, which is the standard measure of obesity, is calculated by dividing a person’s weight in kilograms by the square of their height in metres. A score of 25 is the threshold for overweight, and 30 for obesity.

According to the latest government figures, 30 per cent of children are either obese or overweight by this measure. Obesity among children aged 2 to 10 has risen by 7 per cent in the past decade.

Though the results point to genetics as a key factor in childhood obesity, they also indicate the importance of public health policies that encourage children to eat less and to take more exercise, experts said.

Sarah Hiom, director of health information for Cancer Research UK, which partly funded the study, said: “This research highlights the importance of doing all we can to encourage children to eat healthily. If genetic influence is strong we must try to counter these inherited tendencies by providing the healthiest possible environment, and educating parents on the importance of a well-balanced diet and an active lifestyle.

“Our genes have not changed and yet childhood obesity is rising, and the major challenge is tackling the obesogenic environment that we all share.

“That includes looking at education, transport, town planning and so on, and not blaming parents for genetic susceptibilities that are not their fault.”

Genes not poor diet blamed for most cases of childhood obesity - Times Online


Stop feeding kids shite and they won't get fat.

[Arez]

this is the biggest load of crapola ive heard.....its not genetic....when i reached 16 stone it was cos i was eating 5-6 more meals than i shud of aday!!! its cos i was eating more than i shud of simple as, how is it genetic when there wasnt really any fat people before the war ? what so in 60 years are genes have evolved us into being big fat shits.....no its cos kids cant stop stuffing their faces....."ive only eaten a chocolate bar" yeah a 24 kit kat multipack pack more like

[meow]

the only valid genetic proof of this type is the study of identical twins seperated at birth, this evidence doesnt seem to be mentioned here ...

[jazzcat]

and there was me thinking sitting their ar**s playing video games and doing no exercise while their parents ply them with fizzy drinks and pizza was to blame, silly me

[Puratech]

If i read it right, all theyre saying is that identical twins (with the same genes) stay the same weight as eachother, where as non identical twins (with less similar genes) have more diverse weights. Thats all the study seems to proove.

Trying to derive that its the genes that make the difference is stupid, identical twins are much more likely to live similar lives, from sharing the same clothes/friends/hobbies/sports/needles. On the other hand if you had say a girl and boy non identical twin, chances are the boy is gonna go do whatever his boy peers do while the girl does whatever the girl peers do. Thats just a small environmental example.

In terms of the personality and character traits of the twins, identical twins would have the same genes giving them a predisposition to certain traits, be it making them similar in terms of emotional, positive, negative, introvert, extrovert features and the way they react to situations. Comparitively non identical twins are separate different eggs with different genes and despite being born at the same time can be as different as any two siblings. Thats not to say that identical twins are identical personalitys but they tend to have very similar traits, especially if brought up together, more so than regular siblings.

So your identical twins are more likely to be similar and lead more similar lives than non identical twins, which means that its more likely that 1 non identical twin of a pair eats a cake everytime theyre sad.

These studys really are a waste of time/money.

[teflon]

Fat Parents = Fat Kids
Genetics or lifestyle, it could be either, but the original statement seems to becoming more true as it/fat parents propagate.

[Puratech]

Originally Posted by teflon

Fat Parents = Fat Kids
Genetics or lifestyle, it could be either, but the original statement seems to becoming more true as it/fat parents propagate.

IMO its lifestyle in general and in cases of fat kids its often the parent(s) problem with food being passed on. Be it obsession about food which they inadvertently teach the kids, both in terms of excessive snacking and in terms of obsessive dieting.

[teflon]

Why can't people get back to the happy medium where if you are a greedy guts you will get fat, or if you are hyperactive you will be too thin?
Maybe it's the food options available at certain prices in today's supermarkets.

[LippoW]

Jebus freaking X!

All I know that if you eat more than your body consumes you gain weight! Of course our body saves the extra energy, we haven't been able to eat as well as we currently can in the not so distant past. Now the natural selection has gone out of the window the genes aren't going to evolve so that our body would handle the extra gained energy.

[Tagred]

YAAAY i have an excuse. Oh wait, bugger, im too old. Hmmm i'll blame my thyroid instead