Taste Problems and Multiple Sclerosis
The number of people with multiple sclerosis who experience taste problems (aka, taste deficits) is unclear, although some experts believe it ranges from 5 to 20 percent of individuals with MS. A new study from a team at the University of Pennsylvania’s Smell and Taste Center decided to explore this issue further.
Our sense of taste is closely associated with our sense of smell (olfactory). That fact is clearly evident whenever we experience a cold or similar condition in which we temporarily lose our ability to smell…suddenly everything we eat has little to no taste.
Although considerable research has been conducted on other sensory problems among people living with multiple sclerosis, including tingling, numbness, vision problems, and hearing difficulties, little has been done on the sense of taste. In this new study, researchers explored the relationship between taste deficits and myelin damage.
Taste and multiple sclerosis study
A total of 146 people were enrolled in the study: 73 individuals with multiple sclerosis and 73 healthy controls. All of the volunteers participated in a 96-trial taste test that involved four tastes: sweet (sucrose), sour (citric acid), salty (sodium chloride), and bitter (caffeine).
The tastes were administered to different areas of the tongue. All of the participants with MS also underwent magnetic resonance imaging of the brain to determine number and size of lesions.
Here’s what the researchers found:
- Individuals with multiple sclerosis were significantly more affected in their ability to identify tastes than reported in previous studies
- A significant number of people with MS had taste scores lower than the 5th percentile of controls: 15.07% below for bitter, 21.9% for sour, 24.66% for sweet, and 31.50% for salty.
- The taste scores were inversely proportional to the number and volume of brain lesions. More precisely, the worse one’s ability to distinguish tastes, the greater the volumes of lesions in the temporal, medial frontal, and superior frontal lobes and the greater the number of lesions in the left parietal operculum, right anterior cingulate gyrus, and left and right superior frontal lobes.
- Women outperformed the men in both the control and MS groups
The study’s lead author, Dr. Richard L. Doty, director of the Smell and Taste Center, noted in a press release that their findings suggest “that altered taste function, though less noticeable than changes in vision, is a relatively common features in MS.” The importance of this study, he said, was that it can provide better insight into the relationship between brain lesions and taste deficits “as well as the areas of the brain that are more likely to impact the dysfunction when scarred from the disease.”
Doty RL et al. Taste dysfunction in multiple sclerosis. Journal of Neurology 2016 Jan 25 online
Fleiner F et al. Olfactory and gustatory function in patients with multiple sclerosis. American Journal of Rhinology and Allergy 2010 Sep-Oct; 24(5): e93-97
University of Pennsylvania School of Medicine, press release