The relationship of autistic traits to taste and olfactory processing in anorexia nervosa

Abstract

Background: There is a heightened prevalence of autism in anorexia nervosa (AN) compared to the general population. Autistic people with AN experience a longer illness duration and poorer treatment outcomes. Whether sensory differences in autism could contribute to altered taste and smell as a potential maintaining factor in AN is under-explored. The aim of this study was to explore whether autistic traits are associated with taste and olfaction differences in AN. Methods: The study recruited n = 40 people with AN, and n = 40 healthy controls (HC). Smell sensitivity was measured using the Sniffin' Sticks test. Taste sensitivity was measured using taste strips. Participants self-rated their autistic traits using the Autism Spectrum Quotient. Results: There were no significant differences on taste and olfactory outcomes between people with AN and HC. These findings did not change after controlling for the heightened levels of autistic traits in the AN group. No relationship between taste and smell outcomes and autistic traits were identified within the AN group. Limitations: The current study is not able to draw conclusions about taste and smell processing in co-occurring autism and AN as it only measured levels of autistic traits, rather than comparing people with and without an autism diagnosis. Conclusions: No significant associations between autistic traits and taste and smell processing in AN were identified. Future research should consider further exploring this area, including by comparing autistic women to women with AN.

Sweet, Salty, and Umami Taste Sensitivity and the Hedonic Perception of Taste Sensations in Adolescent Females with Anorexia Nervosa

“…Assessment of sensitivity to sweet taste in patients with AN appears to be especially interesting, explaining why most attention has been paid to this matter in the literature. Despite data indicating that AN is accompanied by sweet taste hypogeusia (higher recognition threshold, filter paper disc method) [ 4 ] (reduced detection, filter paper disc method) [ 14 ] other research [ 5 , 6 , 7 , 8 , 9 , 10 , 12 , 13 ] has concluded that this condition does not involve sweet taste perception, which is the same in patients with AN and in people without eating disorders. Therefore, our results corroborate these researchers’ findings.…”

“…Several researchers have demonstrated decreased taste sensitivity in people with AN [ 1 , 2 , 3 , 4 ]. According to others, in patients affected by AN, sensitivity to sweet taste remains unchanged [ 5 , 6 , 7 , 8 , 9 , 10 ]. Taste sensitivity has a significant influence on food intake control, and its evaluation in patients with AN may provide valuable information about disease development and treatment progress.…”

“…Despite the differences in the test group selection, there are major differences in the methodology of taste tests, such as the tastes used, the method of applying the tastes, and the taste modality tested. The most frequently studied taste was the sweet taste, in 12 publications [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 12 , 13 , 14 , 15 , 16 ]; mainly, taste recognition, taste intensity, and taste detection were assessed. The hedonic aspect of the sweet taste was described less frequently in the literature, and its results were contradictory.…”

“…The salty taste perception in patients with AN is the subject of less research [ 2 , 4 , 8 , 9 , 13 , 14 , 15 , 18 ], and the most complete analysis, including the hedonic assessment of sodium chloride solutions, is presented in only one publication [ 16 ]. The analysis of the salty taste perception in patients with AN presented in this paper will help to complete the knowledge in this area.…”

Subjective Taste and Smell Changes in Conjunction with Anxiety and Depression Are Associated with Symptoms in Patients with Functional Constipation and Irritable Bowel Syndrome

“…It is worth noting that depression may result or cause gustatory and olfactory dysfunction. TSCs may cause negative emotions in cancer patients, including disappointment, depression, and sadness [ 9 , 10 ]. One previous study analyzed the data obtained from a nationally representative probability sample of 3005 older American adults and reported an association between any depressive symptoms and olfactory dysfunction [ 11 ].…”