ingestion vs swallowing

ingestion

noun
  • The action of ingesting, or consuming something orally, whether it be food, drink, medicine, or other substance. It is usually referred to as the first step of digestion. 

  • The act of ingesting something into a jet engine. 

swallowing

noun
  • The act of swallowing. 

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