I think if you have to THINK about a decision you are not acting instinctively. Most of our eating is "mindless" consumption.
We're hungry, foods available, we eat what's available and we may eat too much and we may eat foods that we know (although delicious) will promote weight gain.
But it is possible to retrain the brain so that you just don't want, are not attracted to those foods that you don't eat any more.
I've not eaten sweets for ages, in the same way I've not smoked a cigarette for even longer. When I smoked I was as addicted to cigarettes as when I ate sweets I needed them in a similar way.
Once the abstinence from certain foods becomes INSTINCTIVE it isn't a conscious decision any longer.
No one who knows me would offer me a cigarette or a sweet and I wouldn't be tempted to accept but I don't accept that this is an intellectual/cerebral or conscious decision I think we have to enhance our "off switch" and that means increasing our omega 3 DHA status.
When the two halves of your brain are linked effectively the control of impulsivity, the urge to do something you know is fundamentally wrong for you, is reduced because the "off switch" operates BEFORE you have a chance to debate mentally about whether to give in to temptation or not.

It's a bit like fear, if you are not afraid there is no battle with fear so walking through a field of cows even if there is a bull with them raises no stress related hormones so no fear to be battled with. I don't think I'm smug or better than others for not being afraid when walking near cattle any more than I'm smug not wanting cigarettes when others are smoking or abstaining from sweets when available. Our brains can be retrained to make certain decisions instinctively so our conscious minds are not having to actually think about every little decision.
Think about the difference between learning to drive and driving instinctively.
When you have to explain all the observations/actions and reactions a car driver does it's almost impossible to list let alone make decisions on each aspect, but once the mind is trained to drive instinctively then these decisions are automatic.
Your diet choices need to become equally automatic and this is where improving cognitive function with Vitamin D, omega 3 and magnesium are so vitally important.
The brain/belly connection is extremely important and we have to feed our brains as much as our belly.