Ketosis, metabolism, refeeds
Hello all! I understand there is a lot of content in here about ketosis and refeeds but I want to attempt to clarify this idea that refeeds help "boost" your metabolism back up.
McDonald states, "In general, short refeeds, lasting from 5 to 24 hours were used every so often while dieting. Iíve tried them all .... The question is whether or not those programs were optimal. In my opinion, they arenít for several reasons.
One of the factors Iíve been considering to a great degree has to do with the length of the overfeeding period. While itís true that 5 (or 12 or 24) hours of concentrated overfeeding will raise leptin, the more important question is whether thatís sufficient to Ďtellí the brain that youíre fed. While data (especially in humans) is nonexistent, my hunch is no.
Thereís a lag time of several days between the drop in leptin and the drop in metabolic rate (nervous system output) for example; Iíd be surprised if a mere 12 or 24 hours was sufficient to reverse this. Rather, Iíd expect it to take a similar amount of time for the reversal to occur ...
Now, this isnít to say that short carb-loads/refeeds arenít of benefit. They refill glycogen, turn off catabolism and maybe induce an anabolic response to boot. They also let you eat some of the crap youíre really craving which helps psychologically. But I doubt they are sufficient to affect metabolism very much. Instead, a longer refeed is necessary. The drawback, of course, is that longer refeeds have a tendency to put too much bodyfat back on which goes agains the entire goal of dieting."
So can we clarify whether refeeds actually boost the metabolism or not? They have obvious benefits (as he stated), but the main concern is metabolism manipulation. Anyone have any science to back up his claim (or refute it)?