One reason food/eating/dieting is so confusing is there are so many facets; biological, psychological, sociological ...everything influences.

eatingOne biological tidbit that I find really fascinating is the phenomenon of “8 bites”; or at least, I think it’s a fascinating phenomenon. In a nutshell (no pun intended) here’s what happens: When you are hungry and seek out food, or even if you see food and then realize you are hungry, it begins by stimulating your visual and olfactory cortexes. This triggers your brain into wanting the food, which begins a whole process of initially discerning whether or not the food is safe for consumption but then also whether or not it will be satisfying. Believe it or not this process takes as little as 1/18th of a second but can take longer depending on the situation. Just as quickly the midbrain, or limbic system, is kicked into gear in order to interpret whether or not the food will taste good based on historical experience/data.
This, in turn, stimulates the frontal cortex to verbalize desire and interpret like or dislike. In the meantime, the gustatory process (including digestion) begins with the initial interpretation and the onset of salivation. If your medial prefrontal cortex decides that you will enjoy the food you are about to consume it then begins supporting the physiological platform for consumption. With bite 1 your taste buds begin sending information concerning palate and texture and whether or not you actually do like what you are eating to the anterior cingulate gyrus. If you are taking your time chewing and eating slowly enough, by bite 2 you can make a decision whether or not you would like to continue eating this particular item or if you should begin looking for something else. If you are eating quickly it may not actually be until bite 6 or 7 that you register like or dislike of what you are consuming. Of course, this is also entirely dependent on how quickly you are eating and how many things might be distracting you while eating. eating bitesYour palate is your sense of taste. It is comprised of the historical data that you have collected throughout your life and filed away into the “likes” category. So, let’s assume your palate is pleased with what the food you have chosen to consume and you continue to eat, by about bite 8, your lateral and medial prefrontal cortex will begin to have their attention pulled away by other distractions. The desire to eat is being satisfied, the food you have chosen to consume is palatable, now your active brain will begin to look for other things to keep its attention. The cognitive portion of your brain will no longer include palate related information in the roughly 126 bits of conscious processing available to you. In essence, by bite 9, you will stop paying attention to what you are putting in your mouth, chewing, and swallowing. It may also seem like your taste buds have become sensitized and do not, therefore, taste the food as well. eating spaghettiRest assured they are in perfect working order and you are simply experiencing a common case of habituation and selective attention.
Because the midbrain and primal brain are still interested in food, chances are you will continue to eat until the mechanoreceptors in my stomach register volume and send the signal that there is a large enough portion of food in your stomach to feel satisfied. (These receptors also stimulate other processes that check for satiation of nutrient content) If you are not paying attention or if you are eating for reasons other than hunger you may either, not detect or completely ignore the signals of satiety and continue to eat, without actually tasting, past the point of necessary volume. So, it’s useful to change up what you are eating to continue to stimulate the palate and the brain, and it’s also useful to tune in and eat mindfully so your brain continues to engage with what you are eating rather than checking out and allowing you to overeat or make poor food choices.