Why we overeat?

Updated: Jan 10, 2010, 00:00 AM IST

Wellington: Blaming hunger for overeating? Well, you could be making a mistake, say scientists who have found that it’s not necessary that we eat only when we are hungry and finish when we are full.

Food labels, plate size, lighting and music, what`s on our plate, what the person next to us is doing and our subconscious eating routines, are more likely to influence eating behaviours than hunger.

These external factors drive us to overeat and add inches to our waistlines, reports Stuff.co.nz.

By understanding the psychology of eating, it is possible to control eating behaviours, weight and health.

While we don`t want to overeat, the truth is our brains trick us all the time.

They tell us to mindlessly follow the same routines at mealtimes - routines that Dr Brian Wansink, in his book Mindless Eating: Why We Eat More Than We Think, calls "mindless eating scripts". These ingrained routines tell us when to eat; what to eat; and how much to eat.

It takes around 20 minutes for the body and brain to recognise we are full, but most meals in western society are eaten so quickly, they are finished before the 20 minutes is up. Clearly, it isn``t satiation of hunger, which tells us to stop eating.

Rather than consider whether we`re feeling full after each mouthful, we`re more likely to trust our eyes and stop eating by judging what`s left on our plate.

Eyes also mislead. We can`t ‘see’ kilojoules in a meal and we`re not good at estimating the size of a meal on sight. Eyes aren`t good judges of food intake and worse, they`re easily tempted.