There is a school of thought out there that says that all of our dietary problems would resolve themselves of their own accord if only we regained the ability to listen to our bodies as they sent presumably unambiguous signals to our higher faculties as to what was metabolically required. I may even have said something to this effect ( listen to your body ) in the context of fasting. However, if we apply this notion to the question of when one ought to eat, it becomes somewhat more nuanced, and potentially polemic.
While this ought to be obvious to all but the proponents of “The Secret”, desire has never equaled reality and no amount of wishing ever made it so. If you wish to attain the object of your desire, then action is required. That is the fundamental nature of desire … it motivates, literally, it causes one to move! When it comes to the desire for food, it has only been with the advent recent history, within the last 50 to 60 years, that the mere desire for food could be transformed into materialized food by a trip to the refrigerator, the local grocery store, or some fast food restaurant. And even now, this only applies to select portions of the globe. Even in America, as recently as the 1930s, your hunger might have motivated you to go out and try to steal a loaf of bread for your family. The success of this venture, however, was far from certain.
Going even further back than the Great Depression, in pre-agricultural times, hunter gatherers would attest to the capricious and unreliable nature of prey. We can reasonably expect that they might have spent some time of any given day hungry. Even if they were fortunate to have hunting successes every single day, they would still need to bring back their kills to camp for dressing and further preparation before eating, which would have introduced a potentially significant delay from the point when the kill was made, to the point that it was consumed. All of this is to say that the anomalous state of being is one where hunger is absent, rather than one where it is present.
Further, it must be pointed out that the current epidemic of obesity has been aided and abetted by a simplistic notion of eating when one is hungry accompanied by an insensate phobia of “the starvation response.” If you are eating a high glycemic carbohydrate diet, with every meal you will go from a state of normoglycemia, to hyperglycemia, to hypoglycemia : the carbohydrate roller-coaster of blood sugar levels. If you were to resist your hunger pangs while in the hypoglycemic state, you would transition back into normoglycemia as the body’s compensatory metabolic pathways came into play. With that transition, your hunger would abate. On the other hand, if you “listen to your body” and eat again, you are well on your way to type II diabetes. Please keep in mind that here, I am referring to physiologic hypoglycemia, that is, the effect of insulin clearing a bit more glucose than it should, leaving us hungry following a meal. I am definitely not considering the hypoglycemia induced by injecting too much insulin, for example. That condition must absolutely be addressed via the administration of external glucose to forestall a coma.
So, when it comes to intermittent fasting, should you eat when you feel hungry? I would say, probably not. When you fast, you will get hungry, especially if you are transitioning from eating very frequent meals as advocated in certain bodybuilding circles. But again, hunger is normal, and your body will take steps to liberate stored energy to accommodate your needs. You only need to give it a chance to do so. If you are having a legitimate hypoglycemic episode characterized by sweating, nausea, elevated pulse rate, disorientation, then by all means eat. Very few among us will experience these symptoms when forgoing a meal or two. If you happen to be one these individuals for whom fasting induces extreme hypoglycemia, your body will be speaking to you in unequivocal terms, and perhaps skipping meals is just not for you. For the rest of us, things are far less dramatic and manageable. It becomes an exercise in self-control rather than seeking instant gratification.