It is unquestionable that unbalanced food choices are one of the main causes of non-communicable diseases, such as obesity, diabetes, or cardiovascular diseases. It is, therefore, essential to understand what influences food acceptance and preferences. Food sensory perception, in mouth, is one of the factors determining if the individual will eat or reject a particular food. Saliva composition plays an important role in this perception, namely by affecting astringency, basic tastes or even retronasal aroma perception. While the participation of saliva in sensory perception must be considered, it is important to bear in mind that its composition is subject to different sources of variation, ranging from genetic factors (what can explain some of the variations between individuals), metabolism and physiology (e.g. influence of appetite/satiety or other metabolic signals), or even factors such as circadian and circannual rhythms, stress or diet cues. As such, all these sources of saliva composition changes, may be also sources of oral food perception.
In this presentation, the role of saliva in nutrition will be addressed through two complementary views: 1) the participation of this fluid in the sensory perception of food and, consequently, in its acceptance; 2) the effect of food stimuli (post- ingestive or sensory) in saliva composition. The discussion will be directed to show how this double relationship saliva x food (conditioning its consumption, and/or being a reflection of it) has a physiological meaning and how it can constitute an opportunity to shape food perception and to contribute for acceptance of healthy foods.