On phase I of the Ideal Protein Diet, drinking alcohol isnâ€™t just discouraged, it is completely banned. Why, you might ask? When a person is in ketosis (fat burning) during the diet, alcohol can have a severe and dangerous effect by causing a severe drop in your blood sugar. This can potentially be deadly. We strongly encourage on the Ideal Protein Diet, to discuss cravings with your coach and feel free to ask us why certain things are banned, if you have questions.