Causes of Smell, Taste, and Oral Somatosensory Disorders Affecting Eating and Drinking

Abstract

Disorders of smell, taste, and oral somatosensation (irritation, touch, temperature, pain) challenge the ability to consume safe and healthy diets as well as enjoy eating and food-related behaviors. From nationally representative US health monitoring, these disorders are as prevalent as hearing or vision disorders. Olfactory dysfunction is most common among older adults, although aging itself may not be the cause. Primary causes of olfactory dysfunction are sensorineural (e.g., chronic nasal/sinus disease, head trauma, respiratory tract infections) and neurodegenerative (e.g., Alzheimer’s disease). Less vulnerable to loss is taste, especially at levels experienced while eating. Individuals can suffer distorted or phantom sensations (i.e., dysgeusia) related to medications or conditions that disrupt normal interactions between cranial nerves that mediate taste sensation. Oral sensation (integrated taste, retronasal olfaction, and oral somatosensation) can be altered in systemic diseases (e.g., chronic kidney disease), especially if control is poor; by medications that treat and manage systemic diseases (e.g., cancer); and with poor oral health. Normal variation in taste associates with differences in food preferences and nutritional status, including obesity, while chemosensory disorders, if severe enough, can alter dietary patterns leading to weight gain or weight loss. Excessive alcohol consumption and chronic smoking increase the risk of chemosensory disorders directly or indirectly through exposures/conditions that, in turn, cause these disorders. Individuals with chemosensory disorders should have full medical evaluation, including assessment of the impact on eating behaviors, diet quality, and nutritional status. Access to healthcare and medical advances hold continued promise toward prevention and treatment of chemosensory disorders.