When our brain grows and develops it creates neural pathways, as a child this growth is prolific as you would expect and the pathways that we create lay the framework for the messages that travel through our brain thereafter. For me my childhood was full of sugar, sugar for reward, sugar in quick easy processed food meals (my mother wasn't a cook), sugar for treats, even as a baby because I was small my milk was supplemented with condensed milk!!! My brain became hot wired to associate sugar with all things good, comfort, love and a full belly.
What I have learnt though is that although these pathways exist forever we can shut them down. I see them in my mind as becoming a bit like dried out river beds, no flow happening, no messages being stimulated. In respect of sugar we can do this by avoiding food that stimulates and creates flow along that path.
For many people, sugar is not the only thing that starts the flow; processed carbohydrates (flour, pasta, crackers, crisps) do it, blended fruit does it and so does dried fruit. I have learnt through trial and error that these things, along with obviously sugary food, keep the riverbed full of water, meaning the message to keep eating sugar keeps repeating and repeating, making it really hard to resist.
When I realised this and stopped eating obviously sugar filled food PLUS processed carbohydrates, blended fruit and dried fruit the river bed dried out; the messages in my brain telling me to eat sugar miraculously stopped, no triggers, no cravings, zero interest. It seems a miracle but actually it is just hormones and brain chemistry doing it's thing.
BUT here's the thing those riverbeds will be there in my brain FOREVER, they are not dead just dried out and dormant. Eating any of those triggering sugary foods will act like falling rain on a riverbed, a few drops occasionally and it soaks away but any more than that and the momentum and flow of the water will soon create a flood, a tsunami of reawakened desire for the sweet white stuff and some quick hit bliss.
Not knowing this simple fact is why diets fail and people can't break the sugar cycle because unwittingly they are continually adding water to their neural riverbeds.
The area of the brain called the nucleus accumbent is the seat of pleasure, reward and motivation. The neurones within it are activated by the hormone dopamine and ones of the activities that stimulates the brain to release dopamine is eating.
Sugar and sweet foods really light up this pleasure centre in the brain. When we eat too much sweet stuff our body is flooded with dopamine. To help manage this overwhelming flood of dopamine the cells reduce the amount of dopamine receptor sites on the cell membrane. This means that every time we eat sugar we need to eat more to give us the same wonderful blissed out feelings of pleasure explaining why cravings can feel so strong.
So when you give up sugar you are reseting your brain chemistry and establishing normal levels of dopamine in response to eating.