I have to read more about leptin but ray doesn't seem to like leptin,he rarly mentioned it.Oh I see what you mean. Yes for burning fat on a diet you certainly want to keep dietary fat to a minimum. The reason fat is not encouraged on refeeds when carb cycling is that it doesn't increase leptin like starch does. Leptin is a more fundamental hormone than even thyroid. It controls thyroid actually. Interestingly enough sucrose doesn't help too much in raising leptin either. I would be curious to see how lactose performs because many fitness gurus tend to lump it with other sugars and I think that is wrong.
With regard to fat/carb intake and inflammation it really depends. Everyone who has good experiences with higher fat levels will say fat is good with all these convincing reasons and those with good high carb/low fat experiences will do the same. Ultimately I think there is a lot of symptom management going on thats leads to dogmatic views on macronutrient intake. If your digestion is impaired and liver is inflamed it can certainly make one views carbs/fats/etc. in such a manner. The ideal macronutrient intake is so variable ( even within one person's life ) that one needs to leave most of the decision making to what their body is telling. And even that requires some diligence because your body is good at telling you what's going on right now but can't necessarily tell the future.