Fat-adaptation is . . . hard to describe. But if you were performing at a certain athletic level before keto, took a hit after starting keto, and are now performing again at (or above) your previous level—that is a very good indication of fat-adaptation. Adaptation takes generally six to eight weeks (in some people even longer), because it involves certain shifts in hormone and enyzme production in muscle cells. I’m sure that mitochondrial healing/reproduction is probably also involved, as well.
Another sign of fat-adaptation is increased mental clarity and all-round energy level. But if you are an athlete, performance is the most clear-cut and most objective measure.
Oh, and finally: many people experience a rise in their serum glucose levels after fat-adaptation. This is because once they become fully fat-adapted, the muscles prefer to metabolize fatty acids over glucose and even ketones, thus sparing them for the cells that must have them (the red blood cells have no mitochondria and therefore cannot survive without glucose, and the brain really thrives on β-hydroxybutyrate, one of the ketone bodies). The sign of this “physiological insulin-resistance,” or “glucose-sparing,” as I prefer to call it, is that even though the serum glucose is somewhat higher than it was (earlier on the ketogenic diet, I mean), the HbA1C level remains in the non-diabetic range (under 5.5). This means that the slightly higher level of glucose is actually being used, because it’s not glycating the hemoglobin, as is the case in glycolytic people (a/k/a “sugar-burners”).
Clear as mud, I know, sorry!
. New tub of strips arrived today
