Moderation is a complex topic that people like Sharma tout as being a good rule. It is my opinion that it is a good concept within limits, like Tabasco sauce, spices, salt, and minor issues. For many important problem, moderation is a fools play thing, just like a live poisonous snake. Oh well, shit happens.
If we have an addiction to a food with cravings for more attached, if that food is essentially poisonous to us, allergies, sensitivities, rashes and the like, we need to stay away strictly. I do not need a doctor to tell me that is the best approach, I consider that to be self evident. I do not need a test to convince myself that I am intolerant of something, my reaction to them is sufficient. The down side is that I may be excluding something that is not causing a problem, but little is essential for life. There are those idiots that say we need to develop tolerance to those things through exposure, but to them I say, if I punch you in the face enough times, will you develop tolerance to that?
Placing caps on a serving, such as 100 calories total for one meal of a starchy food, corn, beans, rice, oats may be one way, as long as that does not produce or keep alive an addiction, craving, or other negative issue.
Carbohydrates stimulate insulin, insulin blocks leptin signalling, insulin stores fat in fat cells, and keeps it there. Omega 6 oils cause larger insulin response when carbohydrates are consumed. Weight loss causes hyperinsulinemia, over production of ghrelin, gut peptides and other hormones. Trans-fats and damaged fats are damaging, and should be treated as poison. Likewise sugar in all forms, and sugar like. Wheat Belly by W. Davis. Grains. Beams. Tofu. Dairy. Yeasts. HFCS. There are a lot of potential negative issues. Alcohol is addicting, as is chocolate, and complete abstinence is the only treatment.
There are those too, who are addicted to something, and are unwilling to give it up, but rather limit there consumption it all its effects to some amount, and go through life this way. It works if they can maintain that limit. Some of use are unable to, some not so much. Some people play Russian Roulette to. The safe play is total abstinence. Gamble if you like, it is your life.