The cannabis plant supplies chemicals that closely mimic our own bodies chemicals. So consuming it isn’t bringing foreign or toxic elements on board.
There are genetic differences on both sides (human and plant). Plants vary significantly in potency and concentration of the various cannabinoids in the plant.
SHORT-TERM EFFECTS Sensory distortion Panic Anxiety Poor coordination of movement Lowered reaction time After an initial "up," the user feels sleepy or depressed Increased heartbeat (and risk of heart attack)