Scarring on the brain from MS can impact the ability to identify certain flavors.
Multiple sclerosis (MS) patients are more likely to have issues with taste than previously reported.
A study published in the Journal of Neurology included 73 patients with MS and 73 control subjects, with both groups receiving an MRI of 52 brain regions that impact MS.
When the patients were given a standard taste test — sweet, sour, bitter, and salty – they found that MS significantly influenced their ability to identify different tastes, particularly sweet and salty.
The researchers conducted 96 individual tests that put concentrations of each of the 4 tastes on the left and right side of the tongue. Patients had to identify if the taste was sweet, salty, bitter, or sour, grading it on a scale from “very weak” to “very strong.”
Approximately 15% to 32% of patients scored below the 5th percentile of controls, which is almost twice as high as prior studies. Of these patients who fell below the 5th percentile, 15.07% were for caffeine, 21.9% for citric acid, 24.66% for sucrose, and 31.50% for sodium chloride.
There was also an association of low taste test scores with brain lesion volumes in the temporal, medial, and superior frontal lobes, as well as with the number of lesions in the right and left superior frontal lobes, right anterior cingulate gyrus, and left parietal operculum.
"This study represents the most comprehensive study preformed to date on the influences of MS on the ability to taste," said lead author Richard Doty, PhD. "It appears that a sizable number of these patients exhibit taste deficits, more so than originally thought. This suggests that altered taste function, though less noticeable than changes in vision, is a relatively common feature in MS.”
Researchers also noted that women outperformed men on taste measures, which correlates with previous studies. This is most likely because women have more taste buds and taste papillae than men.
"These findings give us a better insight about that relationship, as well as the areas of the brain that are more likely to impact the dysfunction when scarred from the disease,” Doty said. "Future studies investigating the relationship between taste and MS may help better diagnose and understand the disease, as well as better manage symptoms."