What are ‘digestive bitters’ and what do they do? Digestive bitters are certain bitter-tasting herbs and herbal preparations that help improve digestion. Compounds in the herbs stimulate the bitter taste receptors on the tongue, triggering the production of digestive enzymes in the mouth, stomach, and pancreas. This is why they're often eaten before a meal to get the digestive juices flowing and stimulate the liver and gallbladder. In fact, bitter herbs have been used since ancient times as reme