There are multiple distinct flavors of diabetes/obesity, as evidenced by the fact that some people have: 1) impaired glucose tolerance (but normal fasting glucose); 2) others have impaired fasting glucose (but normal glucose tolerance); and 3) others have both. This means there isn’t a linear relationship between these phenomena*. There are also: 4) obese patients with normal glucose metabolism; and 5) lean patients with type 2 diabetes.
*I think the great Dr. Kraft may have missed some of the nuances here.
There is not 100% overlap among these, suggesting [confirming] distinct diabetes/obesity phenotypes (and probably causes & best treatments).
Is ad lib keto optimal for all of them? No, but it’s a great hack for at least some of ’em, for a specific period of time. It works for people in whom the underlying pathology is related to insulin resistance. And it loses efficacy when the underlying pathology is managed (I think). How? Unknown.
if you consider yourself nutrition-savvy and think “everyone needs SOME degree of carb restriction, the only question is: how much?”
— smarf dos (@smarfdoc) July 30, 2015
For the record: I’m not backing down on ketoadaptation and physical performance. If keto was a total exercise #fail, then it would be very clear in studies on athletes, Wingate performance, etc… some mixed findings out there (partly due to study design issues), but clearly not #fail.
But this post isn’t about that.
Consider two scenarios:
1. An obese insulin resistant patient with elevated fasting and/or postprandial insulin adopts a ketogenic diet. Appetite spontaneously declines, fat mass declines, and overall metabolic health improves. After a while, the patient needs to more closely monitor fat intake… worded another way, they need to start counting calories #CICO. After a while, they may not need a pencil & paper, but still “not eating all the food” becomes important for weight loss maintenance.
2. But not all forms of obesity are associated with insulin resistance. See studies by Cornier and Pittas. And studies by Cornier, Pittas, Ebbeling, and Johnston (although Johnston is admittedly a stretch on this point) show that treatment efficacy differs based on insulin sensitivity. Some of these patients actually do better monitoring calories and restricting fat intake than with ad lib carb restriction. This, I suspect, is due to different underlying pathologies (related to insulin in this case).
For the others, maybe it’s an inflammation/leptin thing. Maybe it’s related to food additives or sensitivities or something else entirely. Point is, keto isn’t the optimal diet for everyone – that’s like saying one cancer drug should cure all cancers.
New study: despite having less protein and more carbs, the Paleo diet outdid the ADA diet. HbA1c, fasting glucose, and insulin sensitivity were all improved despite more carbz.
IMHO, Gary Taubes and Chris Gardner have greatly advanced our understand of obesity. Alternatively, one could say Gardner has filled in one hole of Taubes’ theory, but I suspect there are many more holes…
Another pioneer is Nedeltcheva et al., who showed that simply sleeping better (despite eating same diet) improves body composition.
Try to find out the underlying problem before blindly advising carb restriction. Sleep? Stress? Even fitness/sedentary’ness may be the low-hanging fruit for some.
Carbz are one piece of the puzzle, but if someone’s drinking regular soda and playing on their smart phone late at night, might be better to start there than jumping straight to KETO + IF.
P.S. please don’t come at me with some “ice age” fairy tales, or saying ketosis is the one true human diet, or that LCHF=effortless fasting. I said “please,” bro