A product obtained by heating at least one substance selected from the following (a), (b) and (c). (a) uronic acid or uronic acid derivative; (b) a saccharide compound containing uronic acid or a saccharide compound containing uronic acid derivative; and (c) a substance containing a saccharide compound containing uronic acid or a substance containing a saccharide compound containing uronic acid derivative; and food, beverage or a pharmaceutical agent which is characterized in containing the above-mentioned heat-treated product.