There's a podcast with Kiefer and Robb Wolfe that talks about how the dirty carbs are the best for CBL because of insuline spike lengths. Dirty carbs will spike you real fast then bring you back down, while stuff like yams and sweet potatoes will keep your insulin levels elevated much longer. So you sorta get the spike, prolong it for a few hours by constant feeding, then wake up in the morning with low insulin sensitivity. It's explained in the PDF but on a pretty advance level. I actually did due diligence and got blood work before starting this diet. I'm going to check it in 2-3 months and see if anything has changed. I'm going to start testing with cleaner foods too that will spike insulin fast, like a lot of gluten free items (fruity pebbles are gluten free). Also eating grassfed beef and mostly organic stuff.