There's a wonderful priest who does tons of work on addiction and codependency. Fr. Richard Rohr.
He says codependency underlies addictions and I have found that is definitely my story.
And yes, sugar affects the brain. OA's don't eat it because they become addicted to the high.
Each one us has tondo our own work so we can recognize how different substances affect us. If it blocks us, it needs to he removed.
For me, God allowed me to keep each of my addictions for a certain amount of time. When it was time to give each one up I was in a ton of emotional pain beforehand because the change was needed.
But we need something to put in it's place (a connection with God - hence the 12 Steps.)