Bitter principles, often derived from various herbs such as gentian, wormwood, and dandelion, have a long history of traditional use to support the stomach and digestive health. In traditional European herbal medicine, as well as in Ayurveda and Traditional Chinese Medicine, bitter-tasting herbs were commonly prescribed as "digestive bitters." The underlying belief is that the bitter taste stimulates saliva and gastric secretions, thus "waking up" the digestive tract and improving overall digestion. This practice is rooted in centuries of empirical observation rather than modern clinical trials.

Although robust scientific validation is limited, there is some physiological basis for their use. The taste receptors for bitterness are present not only in the mouth but also throughout the gastrointestinal tract. Activation of these receptors has been shown in some studies to stimulate the secretion of digestive enzymes and gastric acids, potentially enhancing digestive function. However, much of the support for the use of bitter principles in aiding the stomach is still based on traditional knowledge and anecdotal evidence rather than large, controlled clinical trials.

In summary, the use of bitter principles to support the stomach is primarily justified by tradition, with a moderate amount of indirect scientific support regarding their ability to stimulate digestive secretions.