Chewing something that also causes you to salivate makes your stomach produce more acid in preparation for digesting whatever it is: http://www.ncbi.nlm.nih.gov

Chewing something that also causes you to salivate makes your stomach produce more acid in preparation for digesting whatever it is: http://www.ncbi.nlm.nih.gov/pubmed/3376919 http://www.ncbi.nlm.nih.gov/pubmed/3376919