Answer:
internal influences: such as genetics or alrdy existing conditions
external examples: pollution, healthcare system quality and maybe prices
positive and negative effects can occur due to your diet and eating habits, if you meet your nutritional needs, restrict from overeating, if you eat consciously and socially, or on the run to the next meeting
the health triangle is like three pillars, if one comes short, you'll probably get out of balance sooner or later and get problems one way or another.
spirt can be get for you, but also poses risks like injuries or some conditions
(tour de France bikers for example sometimes have to get up in the night and ride the pulse in for not clogging up their blood. 25bpm can be dangerously low, yet a very big heart can pump enough liters per time)