Non-Invasive Vagus Nerve Stimulation Boosts Food Liking in Depression

In a new study, right transcutaneous auricular vagus nerve stimulation (taVNS) acutely improved food liking in patients with major depressive disorder (MDD), especially those with greater anhedonia.1 Although taVNS did not affect “wanting” or motivation for food, it may restore normal hedonic responses, offering promise as adjuvant therapy for reward-related deficits in depression.

“In line with previous reports of anti-depressive effects of VNS, we found that acute taVNS increased liking of food cues in participants suffering from MDD, but not in [healthy controls,” wrote study investigator Vincent Koepp, from the Tübingen Center for Mental Health at University of Tübingen in Germany, and colleagues.1

Investigators assessed the acute effects of taVNS on food liking and wanting ratings, as well as on ratings for non-food items. In total, 31 patients with MDD completed food-cue reactivity tasks to measure taVNS effects and 2 questionnaires to assess symptoms of reward processing: the Sanith Hamiliton Pleasure Scale and the BAS subscale of the Behavioral Inhibition System/Behavioral Activation System questionnaire.

As a control condition, patients underwent sham stimulation, mimicking the TaVNS without activating the vagus nerve. During the sham sessions, participants rated food images as significantly more liked and wanted than non-food images (P <.001). Ratings of food liking and wanting did not differ between healthy control participants and those with MDD (P =.625 and P =.532). However, individuals with MDD showed less preference for low-sugar foods (P =.046).1

Across all participants, active taVNS did not significantly change liking or wanting ratings compared to sham (P =.248 and P =.462). However, a group difference emerged: taVNS significantly increased food liking in participants with MDD but not in healthy controls (P =.027). The study observed no significant changes in wanting from active taVNS to sham (P =.466).1

These results were consistent after adjusting for variables such as antidepressant use, metabolic factors, session timing, and wanting ratings. Exploratory analyses found no specific group or stimulation effects for particular food categories, such as high vs low calorie or sweet vs savory.

During the sham stimulation, greater anhedonia scores were associated with lower liking rates of foods low in sugar and fat (P =.018). With active taVNS, participants with greater anhedonia continued to show stronger increases in food liking (P =.029); this remained significant after accounting for overall depression severity and wanting ratings. The study did not observe an association between anhedonia and taVNS-induced changes in wanting.1

Across all patients, taVNS effects were negatively correlated with the individual hedonic response (P =.002). For instance, individuals with lower baseline liking for food experienced the greatest increases after taVNS, while those with a greater baseline liking showed little or no change. This relationship suggests that taVNS may normalize hedonic processing by enhancing food liking in those with blunted pleasure responses.1

“Our result that taVNS increases food liking specifically in patients with MDD and, in general, in participants with low average food liking and higher scores of anhedonia, helps reconcile conflicting earlier findings in human research,” investigators wrote.1

For example, invasive VNS has been shown to both increase and decrease sweet food ratings in patients with MDD, suggesting that VNS effects may depend on individual characteristics.2 Conversely, studies in healthy participants have generally reported no consistent taVNS effects on food liking or intake.3

“We conclude that taVNS may help to improve aberrant food reward responses while exerting little effect on moderate liking ratings,” investigators wrote.1 “…taVNS may be a promising therapeutic tool to acutely improve alterations in food reward processing. Our finding that greater anhedonia is associated with stronger taVNS-induced improvements might help allocate taVNS as an adjuvant treatment according to a patient's individual profile in the future, which is in line with calls for a more personalized approach in psychiatry.”

References

1. Koepp V, Klaus J, Ferstl M, Müller FK, Kühnel A, Kroemer NB. Non-invasive vagus nerve stimulation normalizes food liking and improves liking ratings in depression. J Psychiatr Res. Published online October 9, 2025. doi:10.1016/j.jpsychires.2025.10.012

2. Bodenlos JS, Kose S, Borckardt JJ, et al. Vagus nerve stimulation acutely alters food craving in adults with depression. Appetite. 2007;48(2):145-153. doi:10.1016/j.appet.2006.07.080

3. Alicart H, Heldmann M, Göttlich M, Obst MA, Tittgemeyer M, Münte TF. Modulation of visual processing of food by transcutaneous vagus nerve stimulation (tVNS). Brain Imaging Behav. 2021;15(4):1886-1897. doi:10.1007/s11682-020-00382-8