Scientists have found by using MRI images of the brain that after a period of fasting, that we experience a hunger or craving for high calorie foods.
Three regions in the brain: the ventral striatum, insula and amygdala are responsible for reward, craving and emotion experience and increase of activity when people subjected to fasting are shown pictures of high caloric foods.
Pictures of high caloric foods register a greater brain activation than low caloric foods. (1, 2)
In an experiment conducted in the documentary “10 Things You Need to Know About Losing Weight” you can see MRI images of the brain showing differences in brain responses to high and low caloric foods after skipping breakfast.
The basic explanation is that the brain responds to Ghrelin – a hormone that is released when the stomach is empty.
The brain’s interpretation of Ghrelin’s message is that fuel will be needed soon, resulting in a powerful feeling of a need for high calorie food to compensate for a lost meal. (3)
The primitive response to hunger which is usually stronger than our will-power will cause cravings for high energy foods.
NUTRITION FACTS VS NUTRITION MYTHS
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