Dr Hirsh who is the initiator of smell and taste treatment and research foundation in Chicago of America, discovers that some food's fragrance can control people's appetite. In the research, he lets 3193 people who are 18-64 year old smell some food's odor before meals, such as the banana, green apple, peppermint, garlic, onion and so on.
As a result, these people reduce 5 pounds/month in 6 months. The effect of losing weight by smelling garlic is relatively more obvious.
Human sensory nerve research lab in Washington has also proved Dr. Hirsh's theory. Dr. Hirsh also specially mentions that because of the female's inborn acute smell, they are more suitable than the male to smell therapy.