If you’ve been following my blog or reading my book Ketone Power, you know I’ve already approached the benefits of ketogenic nutrition over the long-term. When you enter ketosis and you maintain it long-enough (at least a couple of weeks) you start keto-adapting.
I began eating very-low-carb-high-fat as of October, 2013. I’ve been in a state of ketosis most of the time ever since. There were a few exceptions but I’ve never been out of ketosis for more than 12 consecutive hours.
Keto-adaptation is a term introduced by Steven Phinney and widely used by the fans of the ketogenic way of nourishment (won). Keto-adaptation occurs as the body maintains ketosis for the long-term (it starts after a couple of weeks) and it basically happens when your body produces the enzymes necessary to support fat metabolism as the primary source of fuel. It also involves mitochondrial biogenesis (creation of new mitochondria) for the same purpose.
Your body adapts to using fat as the primary source of energy.
One of the most interesting and valuable benefits of keto-adaptation is the loss of hunger and cravings. It’s probably been a few months since I stopped feeling hungry. It’s great because my life does not revolve around meal planning, preparation and eating every couple of hours.
Besides, keto-adaptation seems to enhance my thinking, sharpen my focus, and keep my emotions stable.
I remember that when my primary source of fuel was glucose, I couldn’t think clearly when I was hungry and that I had to eat every 3-4 hours. Being a very busy person, that’s definitely not feasible.
My current eating patterns are random. There are days when I eat only once, there are days when I eat 3 meals, and there are days when I do total fasting. This flexibility is amazing.
Scraping the surface of bio-chemistry and the mechanisms of hunger suppression under keto-adaptation, I would say that as you finished burning the energy provided by the food you consumed, your body automatically shifts to using its own fat stores. The shift is un-noticeable in this state.
Reduced insulin activity is another key factor. On carbohydrate metabolism, after eating (post-prandial) your blood glucose increases along with the production of more insulin because it has to support the entrance of glucose into the cells (mediated by the GLUT receptors). Once the energy from food has been used, your blood glucose drops and this stimulates hunger. The mechanism is much more complex than that. Here’s an illustration from Jeff Volek’s presentation:
Again, when you’re keto-adapted, insulin activity is reduced post-prandially because the primary source of fuel for your cells derives from fat. Your body does not enter into panic mode and starts expressing hunger because there is no major fluctuation of blood glucose and because it knows it can rely on fat.
Various hormones play an important role in this process, such as: grehlin, leptin, glucagon, and insulin to name a few.
I believe that my hunger suppression is also related the fact that I’m using Cold Thermogenesis. Thanks doc Kruse.
I’ve learned that CT has big connections to the hypothalamus, to leptin signaling, and to the thyroid gland. Simplistically, if you use CT for a longer period of time (more than 2 weeks – as per Dr. Kruse) and you become cold adapted, this helps by reducing hunger, increasing fat burning, and regulating leptin activity.
I’ve recently read an older paper on the psychology and physiology of hunger (thanks Bill) and I learned that the lateral hypothalamus and the vagus nerve have deep implications in hunger regulation.
Back in the 80s they didn’t know about leptin and its signaling to the hypothalamus. They considered it an unknown mechanism as they experimented on mice. Leptin was later discovered in the 90s.
Anyway, my point is that keto-adaptation (prolonged ketosis) + Cold Thermogenesis do fantastic job in reducing hunger and cravings. I’d force strength training into the mechanism, but we’ll talk about it later.
These have been widely addressed in Ketone Power, so if you wanna know more, here’s the link. Bottom line is that a good sign of keto-adaptation is the loss of hunger. It means your body starts efficiently using its own fat storage for fuel generation.
Any thoughts and concerns you may have, shoot them in either of the comment sections below. Feedback is highly appreciated.
1. Friedman, M. I., & Stricker, E. M. (1976). The physiological psychology of hunger: a physiological perspective. Psychological review, 83(6), 409.
2. Phinney and Volek – The Art and Science of Low Carbohydrate Living
3. Maria Emmerich – Keto-Adapted
4. William Lagakos – The Poor Misunderstood Calorie
5. Konturek, P. C., Konturek, J. W., Cześnikiewicz-Guzik, M., Brzozowski, T., Sito, E., & Konturek, S. J. (2005). Neuro-hormonal control of food intake: basic mechanisms and clinical implications. Journal of physiology and pharmacology: an official journal of the Polish Physiological Society, 56, 5-25.
6. Kim, G. W., Lin, J. E., Valentino, M. A., Colon-Gonzalez, F., & Waldman, S. A. (2011). Regulation of appetite to treat obesity. Expert review of clinical pharmacology, 4(2), 243-259.
7. Andrews, R. (n.d.). All About Appetite Regulation. Retrieved from Precision Nutrition