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Eat until you drop

Just another piece of cake...

Have you ever wondered why you just can't stop eating that last piece of chocolate cake, even when you are so full that you can hardly move? The reason for this is quite simple really. For hundreds of thousands of years humans were always on the edge of survival, always on the look out for food. Because we had to hunt for food, rather than drive to the supermarket, we have evolved to track down and consume as much high-energy food as we can. This is because we never knew where our next meal was coming from.

Why can't some people stop eating?

But times have moved on, and thankfully we can drive to the supermarket. So this still doesn't really answer the question why so many people find it so hard to keep their food intake to a sensible amount.

Energy Equation

Rats on junk food!

A recent piece of research may shed some light on the matter. Two sets of identical rats were selected. One set were fed on traditional healthy foods: relatively low in refined sugar and fat. The others were fed on junk food: high in sugar and fat. The results were very interesting: the more junk food the rats ate, the more they wanted.

Humans and rats -­ we're not so different!

It seems that the brain chemistry of humans and rats are really quite similar. There is a pleasure centre in rats' brains that rewards the rat with a burst of pleasure chemicals if it does something helpful to its survival, like eat food.

Junk food or die!

Rats were put in a 'choice chamber' where they could press a lever to stimulate the release of pleasure chemicals in their brain or press a lever that releases food and water. The rats became so obsessed with pressing the pleasure lever that they died of starvation and exhaustion. It seems that rats that eat junk food trigger the release of these pleasure-inducing chemicals. What's more, when the researchers took the junk food away and replaced it with healthy food the rats refused to eat. They starved themselves for up to two weeks.

The pleasure centre

The human brain

This is very much what happens to a human who takes heroin. The heroin stimulates the brain to produce the pleasurable chemicals and the addict will seek this pleasure to the exclusion of everything else, ultimately threatening their own survival. The reason why this may be so important is that the human brain also has a highly-developed pleasure centre. Humans seem to behave the same way when presented with junk food. Take a bite and lots of pleasure chemicals are released. You have just have to carry on eating.

What addiction is all about

The really disastrous effect for addicts of all types and species is that the pleasure centres tend to get desensitised over time. You need more and more stimulation to get the same effect. This is why heroin addicts take more and more drugs or junk food junkies eat more and more fatty, sugary foods. In other words, they tend to lose control. This is what addiction is all about. Experiments like this one may help to explain why so many people overeat and put their health at risk, even when they know how much damage they are doing.

Can you leave half a packet of crips?

The most frequent culprits for overconsumption are junk foods. Junk foods contain very high quantities of fat and sugar, but have little nutritional value. They include sweets, crisps, biscuits, chocolate bars, burgers etc.

Researchers recently found that 98 per cent of children between 2 and 18 eat junk food at some point everyday. So nearly everyone likes junk. In small quantities it's tasty and harmless. Why do so many of us over do it? In the end it may be the biggest argument ever for not letting children eat too much junk. Like all addictions, it may be a lot easier not to start in the first place than to stop!

Uneaten crisps

Am I obese?

To find out if you are obese, overweight, underweight or considered a healthy weight you'll need to work out your Body Mass Index (BMI).

Online BMI Calculator

What does BMI mean?

BMI is defined as a person's weight in kilograms divided by the square of their height in meters (kg/m2).

For example, that's = 12 stone (2 kilograms) ./¡¯ 5.2 = BMI

Each BMI figure is classified within a certain range:

  • 18-25 = ideal
  • 26 to 29 = overweight
  • Over 30 = obese

Health problems caused by obesity

  • Heart disease
  • Type two diabetes
  • Risk of stroke
  • Increased risk of liver disease
  • Deep vein thrombosis(DVT)
  • Certain cancers

These are just a few of the problems and the list just goes on and on. In fact, a recent study shows that people who have a BMI over 30 have a 50 to 100 per cent have an increased risk of premature death compared to individuals with a healthy weight.

So, obesity really is a big problem!

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