Saliva is a basic fluid found in organisms ranging from insects to humans, and it contains several molecules needed for normal physiological functioning. Environmental factors activate salivation, so saliva is a critical bridge in translating external stimuli into biological responses. Saliva is normally considered a rich source of digestive enzymes, and studies show that it contains more than 1,000 proteins and other biologically active molecules that influence the body’s functions. For instance, people with depression produce less saliva, and “dry mouth” occurs alongside several chronic psychosomatic conditions. Clearly, normal salivary flow is important to good health, but it can also be affected by treatments such as radiation therapy for head and neck cancers. Reduced salivary flow results in dramatically reduced quality of life, so strategies for activating salivation are needed to manage dry-mouth conditions and the symptoms that go with them.

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