constipation vs tightening

constipation

noun
  • The act of crowding anything into a lesser space, or the state of being crowded or pressed together; condensation. 

  • A state of the bowels in which the evacuations are infrequent and difficult, or the intestines become filled with hardened faeces 

tightening

noun
  • The act or process of making more tight. 

How often have the words constipation and tightening occurred in a corpus of books? (source: Google Ngram Viewer )