Why are we so fat? The list gets longer!

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Why are we so fat? The list gets longer!

Medical Research News

Published: Wednesday, 28-Jun-2006

If you were beginning to suspect that the list of things which could

make you fat seems to be growing longer on an almost daily basis -

you were right!

New research is now saying that obesity in the U.S. cannot just be

blamed on diet and lack of exercise.

In a review of data on possible causes of obesity, the contention

expressed is that many aspects of modern living from lack of sleep -

to exposure to environmental chemicals - to living with air

conditioning - may be contributing factors in the obesity stakes in

America.

The researchers say that obesity research and prevention strategies

need to look beyond food industry practices such as portion sizes

and added sugar and reduced physical activity, because a range of

other factors are just as plausible.

Dr. B. director of the Clinical Nutrition Research

Center at the University of Alabama, says that diet and exercise are

undoubtedly important but the evidence linking obesity to food

industry marketing and lack of gym class is circumstantial.

, a co-author of the report says there is other evidence

which suggests that a chronic lack of sleep boosts appetite and

eating, and studies show that U.S. adults have gone from sleeping

for an average of 9 hours to about 7 hours.

Industrial chemicals that act as endocrine disruptors may also

contribute to an increase in body fat as they alter hormonal

activity when they get into the body and people have been

increasingly exposed to such chemicals through the food chain in

recent years.

Air conditioning too may be a factor as the body burns calories when

forced to regulate its own temperature and people tend to eat less

in hot, humid weather.

and colleagues have come up with a list of 10 potential

obesity risk factors which include increased rates of older mothers,

whose children may be more prone to excess weight gain; a range of

medications, such as antidepressants, which can promote weight gain;

and a decrease in smoking rates, because people often gain weight

when they quit and the absence of nicotine, an appetite suppressant

encourages snacking.

Genetic factors, such as the heritability of a person's body mass

index (BMI), could also be a factor as studies show that BMI has a

heritability of about 65 percent.

According to he is not suggesting people should stop taking

their prescriptions, keep smoking or turn off the air con, and he

says diet and exercise remain key factors in obesity.

believes researchers and policymakers should be " open-

minded " about the potential contributors to the obesity problem and

not assume that the answer lies in simple solutions such as banning

fizzy drinks from schools or installing sidewalks to encourage

walking.

Some experts question the claims and say as people stay thin in all

different climates, it is unlikely air conditioning plays much of a

role and they are also concerned about linking obesity to genetics.

The review is published in the International Journal of

Obesity.