The first people of this civilization reached India from Africa in 40,000 BC. At first they were hunters and gatherers but in 4000 BC they became farmers. The Indus valley farmers grew wheat, grains, and animals on land. Cows, goats, and sheep gave milk and alternatives. They cooked on hearths and grounded grain into flour by rubbing a rounded stone across on top of a flat stone. Bread, and porridge were part of everybody's diet. They mostly ate veggies and fresh or salted fish. The rich ate meat.
http://www.bbc.co.uk/schools/primaryhistory/indus_valley/food_and_farming/
http://www.bbc.co.uk/schools/primaryhistory/indus_valley/food_and_farming/