A comparative study on the physiological taste threshold in hypothyroidism and normal controls

Background: Taste, one of the five special senses, is the sensory impression of various substances on the tongue. There are five basic taste modalities such as sweet, salt, sour, bitter, and umami. The physiological taste threshold of the individual gets altered in hypothyroidism. Aims and Objectives: The present study was undertaken to test and compare the physiological taste threshold for the five primary taste modalities such as umami, salt, sweet, sour, and bitter in hypothyroid patients and the normal healthy controls. Materials and Methods: Thirty hypothyroid patients aged between 20 and 50 years and 30 age, sex, and anthropometrically matched apparently healthy individuals as control were included in the study. The tests for the threshold of all the five primary tastes were performed in both the groups and the results were compared. Results: The taste threshold for the sweet taste modality has been increased significantly (P < 0.05) in hypothyroid patients compared to controls. No difference could be observed in case of other taste modalities. Conclusion: The significant increase in the physiological taste threshold of sweet modality in hypothyroid patients compared to the controls suggests that hypothyroid patients may have a decreased sensitivity for the sweet taste. Thus, the taste dysfunction should be detected in them by proper screening. Timely management/treatment and counseling can help them to get back their normal taste threshold along with attaining the euthyroid status.