Killer carbs -- Monash scientist finds the key to overeating as we age

August 21, 2008

A Monash University scientist has discovered key appetite control cells in the human brain degenerate over time, causing increased hunger and potentially weight-gain as we grow older.

The research by Dr Zane Andrews, a neuroendocrinologist with Monash University's Department of Physiology, has been published in Nature.

Dr Andrews found that appetite-suppressing cells are attacked by free radicals after eating and said the degeneration is more significant following meals rich in carbohydrates and sugars.

"The more carbs and sugars you eat, the more your appetite-control cells are damaged, and potentially you consume more," Dr Andrews said.

Dr Andrews said the attack on appetite suppressing cells creates a cellular imbalance between our need to eat and the message to the brain to stop eating.

"People in the age group of 25 to 50 are most at risk. The neurons that tell people in the crucial age range not to over-eat are being killed-off.

"When the stomach is empty, it triggers the ghrelin hormone that notifies the brain that we are hungry. When we are full, a set of neurons known as POMC's kick in.

"However, free radicals created naturally in the body attack the POMC neurons. This process causes the neurons to degenerate overtime, affecting our judgement as to when our hunger is satisfied," Dr Andrews said.

The free radicals also try to attack the hunger neurons, but these are protected by the uncoupling protein 2 (UCP2).

Dr Andrews said the reduction in the appetite-suppressing cells could be one explanation for the complex condition of adult-onset obesity.

"A diet rich in carbohydrate and sugar that has become more and more prevalent in modern societies over the last 20-30 years has placed so much strain on our bodies that it's leading to premature cell deterioration," Dr Andrews said.

Dr Andrews' next research project will focus on finding if a diet rich in carbohydrates and sugars has other impacts on the brain, such as the increased incidences of neurological conditions like Parkinson's disease.

Source: Monash University

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4 comments

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TheRogue
not rated yet Aug 21, 2008
This "scientist" has obviously never heard of leptin, the most recently discovered and by far most powerful of the hormones in our bodies.
GrayMouser
5 / 5 (1) Aug 21, 2008
I don't want anyone telling what I can or can't eat!

I would rather enjoy my life (and live a few years less IF these "experts" are correct) than be miserable doing what ever the current fad is. Considering the reduced stress I might out live them anyway.
irjsi
5 / 5 (1) Aug 21, 2008
GrayMouser,
AMEN ! ! !
Eat Margarine; don't eat margarine . . .ad infinitum.
When asked:
"What are you doing for your Health?"
As one Person replied:
"I don't drink cheap whiskey !"

Roy Stewart,
Phoenix AZ
Keter
not rated yet Aug 25, 2008
Let's see...eating too much sugar/carbs causes insulin resistance and now it causes brain cell death, both of which set the stage for more hunger and excessive weight gain. This is true. But where are all the excess sugar and carbs coming from? Most people really don't seek that, and don't understand why they have so much trouble losing weight.

I suggest each person keep a food diary for a couple of weeks to find out what you're really eating. As a person who is allergic to wheat (not gluten, wheat itself since it became 100% GMO), I have found it incredibly difficult to avoid foods that contain wheat, usually in the form of some starch used as a filler or binder. In processed foods, most of the 'food' is filler with a coating of fat, sugar, or flavoring (junk) on it to make it taste okay.

Try eating lunch - and find yourself having to order a salad or off the dinner menu: everything is cooked with pasta, breaded and fried, or served on a bun or flour tortilla. Even some corn chips now contain wheat. Most packaged foods now have "modified food starch" in them - a simple wheat starch that breaks down almost immediately into sugar. Read the labels...you'll find that if you avoid eating crap, about 90% of today's "food" products are suddenly off the menu for you...

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