Food and beverages for improving abdominal discomfort, comprising a composition comprising 1,4-dihydroxy-2-naphthoic acid obtained by(i) a process for producing 1,4-dihydroxy-2-naphtoic acid comprising initiating the culture of 1,4-dihydroxy-2-naphthoic acid producing bacteria belonging to propionic acid bacteria under anaerobic conditions and culturing the bacteria under aeration into the medium when the concentration of a carbon source in the medium is 3.5% by mass or less, or(ii) a process for producing 1,4-dihydroxy-2-naphtoic acid, comprising culturing 1,4-dihydroxy-2-naphthoic acid producing bacteria belonging to propionic acid bacteria under anaerobic conditions, adding a carbon source to the obtained culture and preserving the culture at 3 to 20 °C under weak alkaline conditions, or(iii) a process for producing 1,4-dihydroxy-2-naphtoic acid, comprising initiating the culture of 1, 4-dihydroxy-2-naphthoic acid producing bacteria belonging to propionic acid bacteria under anaerobic conditions, culturing the bacteria under aeration into a medium when the concentration of a carbon source in the medium is 3.5% by mass or less, adding the carbon source to the obtained culture and preserving the culture at 3 to 20 °C under weak alkaline conditions, as an active ingredient.
