A study on factors influencing thirst perception during oral nutritional supplement intake in cancer patients

Cancer patients undergoing treatment frequently experience malnutrition due to disease-related factors and side effects of therapies like chemotherapy and radiotherapy. Oral Nutritional Supplements (ONS) play a pivotal role in maintaining nutritional status and improving treatment outcomes. However, adherence to ONS is often poor, influenced by sensory properties such as taste, viscosity, saltiness, and protein content. Thirst perception, an underexplored factor, may also impact ONS adherence, particularly in patients managing xerostomia, dysgeusia, and other treatment-related changes in oral sensations. This cross-sectional sensory evaluation study included 56 cancer patients, of whom 29 participated in detailed sensory testing. The study systematically evaluated the effects of varying salt levels, protein concentrations, and viscosity in ONS formulations on thirst perception, mouth dryness, and sensory acceptability in cancer patients. Modified ONS formulations, including low, medium, and high levels of salt, protein, and viscosity, were compared to a control. Participants completed sensory evaluations using visual analogue scales (VAS) and hedonic scales to rate thirst, mouthfeel, taste, and overall liking. Subgroup analyses examined the influence of patient-specific factors, such as dysgeusia and hydration habits, on these responses. Results indicated that high-salt (1g) and high-protein (5.5 g protein/30ml) formulations were associated with higher thirst perception (VAS scores ≥45 mm) compared to low-salt (0.33g) and low-protein (4.7g protein/30ml) formulations (VAS scores ≤27 mm). Low-viscosity (50 cP) formulations were preferred for their smoother texture, while high-viscosity (250 cP) samples elicited greater thirst due to mouth-coating effects. Dysgeusia amplified thirst and reduced liking scores for high-salt and high-protein ONS. These findings highlight the need for patient-centred ONS formulations that minimize thirst stimulation while enhancing palatability. Optimizing ONS properties may improve adherence and nutritional outcomes for cancer patients, although further studies are needed to confirm any direct impact on quality of life or treatment outcomes.