The present invention pertains to the use of the calcium-sensing receptor (CaSR)-activating nutrients (designated as “CaSR-based nutrients”) for the prevention and/or treatment of diarrheal diseases and inflammation in the gastrointestinal tract. In one embodiment, the current invention is formulated for oral administration. The anti-diarrheal composition of the present invention is useful for treating diarrheal and gastrointestinal inflammatory conditions in infants and young children.