 You may not feel lethargy because you're eating small meals but you cannot stop the digestive process. If you want to be at your full potential, within an hour and a half to two, your stomach should be empty. When there is food in the stomach, the excretory system shuts down almost. Whole and not being clean means you're asking for problem. See, if you know a human body from within, you yourself look at this. Just see how your body feels when there's food in the stomach and how your body feels when the stomach is empty. You will see your body and your brain will work at its best when your stomach is empty. If food is constantly being processed in your digestive system, a certain amount of energy naturally is gone there. So both your brain and body will not function at their best. You may not feel lethargy because you're eating small meals but you cannot stop the digestive process. When digestive process happens for every other animal after they eat, they sit down. They just sit down because there is not enough energy for other things. Whether Kornivurus or Herbivurus animals, after they eat they sit down and that is a natural need within a human being also. After he eats, he would like to sit down because there is not enough energy for other things. Now you think by eating small meals through the day, you can be active throughout the day. You can be but not at your full potential. If you want to be at your full potential, you must keep your body and your metabolism of the body in such a way. Whatever you eat, whatever you eat, within one-and-a-half to two-and-a-half hours, your stomach must be empty. This is what yoga always insists. Within an hour and a half to two, your stomach should be empty. Stomach being empty does not mean hunger. Only when the energy levels run down, you feel hunger. Otherwise, stomach must be empty. Only when the stomach is empty, stomach means stomach back, the food would have moved to other areas of the intestine. In the intestine, the process is very different. That's not digestion, that's assimilation. There, it doesn't take much energy. It's a digestive process. When the food is in the stomach bag, at that time, it's best you keep your activity at low. Now throughout the day, if there's food in the stomach, then you bring down your whole potential of life. One more aspect. When there is food in the stomach, when the digestive process is happening, the excretory system shuts down almost. Eighty percent of it shuts down. When I say excretory system, it's on the cellular level, the purification of the body is happening, that will shut down at least eighty percent. Or in other words, all the impurities which had to move out of the system will not move out, which will create various problems for you over a period of time. And if you eat at different times, even your excretory system from the intestines will not happen efficiently for you. Because the waste matter doesn't come at a certain time into the colon. It will come at different times. So you will have a problem with that also. So throughout the day, your colon also won't be clean. Colon not being clean means you're asking for problems. The colon should be clean always. And yoga, there's enormous importance to this. In any of the traditional systems, you will see, if you go to an Ayurvedic doctor or a Siddha Vaidya or anybody, first thing is he'll purge you. Because he knows that most of your problems are because of unclean colon. And the way people are eating today, keeping the colon clean is going to be a big challenge for them. Suppose you eat one big meal, like we normally do, one big meal, and either we don't eat anything else or if we are too active, maybe we eat a fruit or something, you will see your colon will always remain clean. And people should try this. They must purge themselves one day and see how it feels. Suddenly there is something light and beautiful about you. Every day that's how you're supposed to feel.