Previous studies have indicated that weight gain can reduce one’s sensitivity to the taste of food, and that this effect can be reversed when the weight is lost again, but it has been unclear as to how this phenomenon arises.
Now a study publishing recently in the open-access journal PLOS Biology by Andrew Kaufman, Robin Dando, and colleagues at Cornell University shows that inflammation, driven by obesity, actually reduces the number of taste buds on the tongues of mice.
A taste bud comprises of approximately 50 to 100 cells of three major types, each with different roles in sensing the five primary tastes (salt, sweet, bitter, sour, and umami). Taste bud cells turn over quickly, with an average lifespan of just 10 days.
Obesity is known to be associated with a chronic state of low-grade inflammation, and adipose tissue produces pro-inflammatory cytokines — molecules that serve as signals between cells — including one called TNF-alpha. The authors found that the high-fat diet increased the level of TNF-alpha surrounding the taste buds.