"Smoking causes drastic changes in the _______ system, which is responsible for converting foods into the nutrients the body needs to survive." This is a question on a health crossword puzzle given to me by my teacher. Problem is, I know nothing about this "system" and have no other way to look it up. What goes in the blank?How many letters are in it and are any of the letters already "inserted" into it? There are 9 letters in it, and the second letter is "i".go to google and type in " what system does smoking make drastic changes in?" Thanks!! :)yupThe system that "is responsible for converting foods into the nutrients the body needs to survive" is the digestive system. I hope this helps a little more. Thanks for asking. what happens when you eat too much