All this is true….its said to be a sakana. Be very careful not too…but again if you do dont think ur going to have a miss that day.
a) the chazon ish says it doesnt apply anymore in our day
b) you can cut off a piece of wood as prevention if you did
b rought by sefer shmiras haguf vhanefesh
c) or cut something whatever you can it is said to protect
ENJOY!