Lets say someone has a very healthy diet, never deviating from it. But that person then wants to eat something "unhealthy" like potato chips. What factors are at play for how long that persons "health" will be affected and what determines how well anyone can eat such things and it not really having a big impact on their health... Is it solely based on how strong their immune system is? Also, once having shit out the potato chips, wont the body have reset to its original state of "health" or at least not having any continuous negative impact as long as no more potato chips are eaten? When will the unhealthiness 'wear of' and what is really going on in depth? What allows one person to eat several bags of chips a day and their health is not really impacted vs someone else barely being able to eat the second bag and realizing he or she should stay far as way as possible from those chips ... What factors are at play for how much one can tolerate unhealthy foods and get away with it?