**5. Conclusion**

The present human experiments have shown that OSM odor is agreeable and elicits sedative effects, improves mood, attenuates hunger, and reduces food intake. Grapefruit odor, which has also been shown to attenuate food intake, activates sympathetic nerve activity and had no effects on expression of feeding-related neuropeptides in rats, which is contrary to the results obtained for OSM odor, indicating the difference of causative neural mechanisms between the two odors. Exposure to OSM odor before eating and that to grapefruit odor after eating may be recommended as the effective practical use for preventing from overeating and obesity.
