On average, digestion takes about 6 - 8 hours for food to pass through your stomach and small intestine. Food then enters your large intestine for further digestion, absorption of water and, finally, elimination of undigested food. The average transit time through just the large intestine is under 40 hours, with significant difference of average between men and women: 33 hours for men, 47 hours for women.

 

Understandably, digestion time varies between individuals as well as type of food being eaten.