To tell the story of what sugar does to your brain, you have to start with the thought that triggers your need for a hit of sweetness.
It often happens in the afternoon when your brain, which runs on sugar, starts to get hungry.
To satiate the craving your brain activates a string of neurons, often referred to as the reward pathway, which pump the chemical dopamine into your brain.
All of a sudden you need a chocolate bar or that sweet pastry you saw at lunchtime.
If you act on that craving, the reward pathway then switches mode, pumping chemicals such as beta-endorphins into your brain, generating feelings of pleasure.
Your brain thanks you for the sugar hit by making the chocolate bar literally taste sweeter, says Dr Zane Andrews, a scientist at Monash University who studies how our brains regulate control of our diets.
But if you respond to the brain’s need for sugar too often, the reward pathway can develop tolerance to the stimulus.
“That means we need to eat more to get the same feeling. That’s a classic feature of addiction,” says Dr Andrews.