When we eat a meal, our body breaks down the food into nutrients such as glucose – a simple sugar that our body uses for energy. Our brain is one of the largest consumers of that energy. About 20-25% of our total energy is consumed by our brain – which is only about 2% of our body weight.
Hunger is a signal that the brain needs more fuel, it’s triggered when the level of nutrients in our bloodstream begins to drop. When the brain runs dry of fuel, it stimulates a stress response. It’s really a survival mechanism.
Our inhibition to different emotions is lowered. And – because the brain needs fuel to function at its highest capacity – we see things like difficulty concentrating, and difficulty controlling emotions.
One of the most common emotions is anger – and that’s why, many times, when we become hungry, we become irritable
But many confectionery companies cynically exploit this to sell more products. Snickers famously released ‘You’re not you when you’re hungry’ ad campaign. This increased their sales by more than 57%, but was later criticized for being sexist, inhuman and immoral by creating an ad that exploits the serious effects hunger can have on a persons abilities.