Reduced olfactory bulb volume in obesity and its relation to metabolic health status

Maria Poessel, Nora Breuer, Akshita Joshi, Andre Pampel, Arno Villringer, Thomas Hummel, Annette Horstmann

Research output: Contribution to journalArticleScientificpeer-review


Smell perception plays an important role in eating behavior and might be involved in body weight gain. Since a body of literature implies that olfactory perception and function is hampered in obesity, we here investigate neuroanatomical correlates of this phenomenon. We assessed olfactory bulb (OB) volume with magnetic resonance imaging in 67 healthy participants with a body mass
index (BMI) from 18.9 to 45.4 kg/m2 (mean = 28.58 ± 6.64). Moreover, we obtained psychophysiological data on olfactory ability (Sniffin’ Sticks, Food associated odor test) and self-report measurements on eating behavior. Additionally, we collected parameters associated with metabolic health in obesity (waist-hip ratio, waist-height ratio, leptin levels, body fat percentage, fat mass index, insulin resistance) to investigate recently proposed mechanistic explanatory models of why olfaction may be altered in obesity. We showed that OB volume was significantly lower in participants with obesity when compared to those of normal weight. Moreover, we found weak to moderate negative correlations between OB volume and BMI and related measures of metabolic health, especially leptin, body fat percentage, waist-height ratio and insulin resistance. However, neither OB volume nor BMI were related to olfactory function in our young and healthy sample. Nevertheless, our results provide first indications that obesity is associated with brain anatomical changes in the OBs.
Original languageEnglish
Article number586998
JournalFrontiers in Human Neuroscience
Number of pages12
Publication statusPublished - 27 Nov 2020
MoE publication typeA1 Journal article-refereed

Fields of Science

  • 515 Psychology

Cite this