That's a start but the physiological response to bread (gluten) is somewhat mimiced when rice, corn, soy, and even dairy are consumed. Your advice can work for a lot of folks but this person sounds far beyond that stage. To really "kick" sugar you're talking dropping out carrots and a whole bunch of other stuff most people don't consider. That's why keto is more likely required here.
JMO over the internet...
I should've said 'refined' sugar.