Can What you Smell Affect How Much you Eat?

It sure can! There's been a lot of work on various scents, and whether or not they can be a useful tool in weight loss. How is it possible that scent could cause us to eat less? First, remember that how food tastes depends a lot on smell. It's a bit complicated....but identifying food is actually determined by smell and sight, rather than "taste". Scientific American published a great article on how this works, if you want an explanation.  (http://www.scientificamerican.com/article.cfm?id=experts-how-does-sight-smell-affect-taste). 

There are specific scents that dull our appetite. Grapefruit, for example, affects the nerves that are below our consciousness, (called "autonomic nerves") and smelling grapefruit reduces both appetite and body weight...in rats, anyway.  (Read the study synopsis here: http://www.ncbi.nlm.nih.gov/pubmed/15862904) Other studies, involving humans, show that the smell of grapefruit may somehow affect liver enzymes to suppress appetite.

Peppermint scent also works. In 2007, a university in West Virginia did a study whereby participants smelled peppermint every 2 hours. The study looked at  hunger levels when the participants smelled peppermint, as well as when they didn't, in addition to how much food they actually ate and what was in the food (e.g., fat intake, caloric intake, vitamin and mineral intake, etc.) over a period of two weeks.
Results showed that participants who were exposed to peppermint consumed nearly 3000 fewer total calories from saturated fat, total fat, and sugar each week. That's about 23% fewer calories based on 1800 calories/day diet for 7 days. Participants also rated their hunger level significantly lower during peppermint inhalation.

Even Dr. Oz has cited this study...as well as supporting the smell of grapefruit as a tool in weight loss. (http://www.sharecare.com/health/weight-loss/article/curb-hunger-with-peppermint)

As in all things, individual results will vary. But here's the good thing: inhaling pure peppermint scent and/or grapefruit, ideally from an essential oil, can't hurt any! There are no side effects to worry about. Something to ponder with our holiday season fast approaching, and, the temptation to overindulge on rich food, or have second helpings!