Overview
- The peer-reviewed trial, published online July 9, enrolled 23 fasted, resistance-trained young men in a randomized double-blind crossover test of 90% dark chocolate, 60% milk chocolate and an odorless control.
- Participants exposed to the 90% dark chocolate odor completed about 18 more leg-extension repetitions than the control and those exposed to 60% milk chocolate completed about nine more repetitions.
- The dark chocolate scent reduced pre-exercise hunger and increased fullness while ratings of perceived exertion rose across sets but did not differ between odor conditions.
- Key limitations include the small, homogeneous sample, the easily recognized odorless control that could have cued participants, and the absence of blood, hormonal, autonomic or neural measurements to explain how the scents might work.
- Because exploratory mediation analyses were inconclusive, experts say the finding is an intriguing early signal that needs larger, blinded and physiologically grounded replication before any practical recommendations can be made.