i dont believe its natural, with respect to our evolutionary history, to eat at fixed times, or with a fixed number of sessions. depending on my athletic endeavors at the current time of year, all i can say is "i eat when my body says to eat"
i also am a very active person
when im not really focused on athletic things, i may purposely not eat for some days, or purposely eat very low amounts of calories. when im trying to spend a short time adding a few pounds, i might eat an inordinate amount of protein at times when my stomach isnt already telling me to do so. that being said, most of my daily caloric intake is seemingly at random. i do the ritualistic dinner meal thing with my life partner in the evenings, but outside of that "meal," the way i eat cant really be recognized as any formal structure.
all that being said, id argue that its a bit awkward, and therefore harmful in the long run (to the overall vitality of the digestive system) to eat exact amounts of food the same every day, to have exact fixed times for eating, and to have a preplanned number of meals. our bodies simply arent adapted, for the long haul, for that sort of rhythm.
i imagine that, with each decade of my life, ill start to regulate my caloric intake a bit more, to a degree that i fast once a week, and consume far less protein (im not convinced the human body requires complex carbs at all).