I Smell You, You Smell Me

Have you ever noticed that when you get a cold, you can’t taste things as well? That the flavors of the food you put in your mouth seem muted? It’s because you can’t smell as well. Our sense of smell is a critical component in our ability to enjoy the flavors of food.  But what else does smell do for us?

Smell allows us to take in airborne chemicals that are sending us messages. For example, pheromones. Pheromones are an odorless, naturally occurring substance excreted by a fertile body that can provide information (and get a response from) the opposite sex. You probably know that animals excrete these sneaky aphrodisiacs, but what about us?

Anyway, a little bit about human odor. About 25 years ago, chemical signals simply called “odortypes” were discovered and research began. Through testing, scientists found that each of us emits odors (where are you hiding, BO?). They may be odorless in the sense that we can’t perceive them the way we perceive stinky socks, but the smell receptors in our noses take them in.

So every human being has these odors, which are defined as an odor fingerprint. They are a signal of self versus nonself in the immune system. What is self versus nonself? Every cell in the body carries molecules that identify it as self (i.e., part of your body). The body’s immune system don’t normally attack tissues made up of cells with a self marker and immune cells and body cells inhabit the same space peacefully. So when a cell or organism shows up in the body without that self marker (called an antigen), the immune system knows it’s foreign and not supposed to be there. It attacks the antigen (nonself) in order to heal the body. There are exceptions, which show up as autoimmune diseases, like gluten allergies and Crohns disease.

Scientists are trying to understand the messages that the chemical signals of our fingerprint tell others. They know that animals use these chemical signals. They use their odor fingerprints to pick a mate based on an unlike odor type instead of a similar one. That means they have disparate immune systems so their progeny will be stronger. Combining two dissimilar immune systems means it can protect from a wider range of diseases. So does that mean we should sniff our significant other’s undershirt?

Another aspect of odor and health is disease detection. Scientists at Monell have done studies that show you can detect various cancers through bodily odors. If there’s melanoma or carcinoma, you can pick it up through the skin.  They also showed that lung cancer can also be detected through odors from the body.  Now there’s a study going on at Penn that tests to see if you can detect lung cancer through the breath. If it all works out, cancer could be detected and treated earlier. High five, smell science!

So, that’s the chemical part of smell. How about how we interpret smell? Like, scents we can actually pick up? Our brains perceive scent based on what we expect to smell. What someone tells you can actually make you think that’s what you smell.

And here’s where testing gets fun.

Testing was done where a group of people was placed in a room. They smelled an odor that was being pumped into the room and were told that it was an aromatherapy agent. They were asked to do things, like simple math problems (2+2=4). After they left the room they filled in a health checklist. Were they tired? Did they have headaches? Were they feeling uncomfortable in any way? Everyone was fine.

A second group of people was put in the room. They smelled the same odor as the first group, but this time they were told it was an industrial solvent. They did the same simple math problems and were asked to fill in the same checklist. People had sore throats, headaches, felt weak and debilitated, all that good stuff. Their expectations influenced their physical reaction to the odor. You’ll get to experience this test first hand, but I won’t tell you what it is. I don’t want to ruin the fun.

A little about the event and it’s moderator. It’s going to be moderated by a brilliant guy named Rob Blackson. Rob is the curator of the art museum at Tyler School of Art at Temple. Monell invited him to moderate the event because five years ago he curated a show in the UK called “If There Ever Was.” The exhibition was about imaginary smells. He created 13 short vignettes that each went with a scent created by perfumers. The exhibition included extinct flowers, magical flowers, the sun, the Hiroshima bomb, Cleopatra’s hair, and a death row prisoner’s last meal. One story was about the first astronauts to go into space in the Russian Mir space capsule. The cosmonauts couldn’t stop drinking vodka. Since they were in space, it metabolized in a funny way. When they got back to earth and the space capsule opened up, everyone just fell over because of the putrid smell of the vodka.

Scientists from Monell know everything about smell. Charles Wysocki, a behavioral neuroscientist in olfaction, will give a brief overview of how the sense of smell works and talk about pheromones – are they there? What do they do? What do they tell us about each other? After, Gary Beauchamp will talk about chemical signals and their health implications. Finally, Pamela Dalton, a cognitive psychologist, will talk about how our body odors send messages about our emotions and stress levels. Whoa, no hiding here!

Plus, there’ll be demos and audience participation. As in, you get to smell stuff too. Good luck…

Esther

April 20^th, 6:30pm – 8:00pm, Society Hill Playhouse, Tickets: $10

To purchase tickets for this event, click here.

Thanks to Leslie Stein

Bibliography:

"Coming up smelling of roses and Hiroshima." BBC - Wear - Places. BBC Wear Website, 5 July 2008. Web. 3 Apr. 2012. <www.bbc.co.uk/wear/content/articles/2008/05/02/smell_exhibition_
feature.shtml>.

Shomon, Mary J.. "Self and Nonself -- Understanding the Immune System, Including Autoimmune Thyroid  Conditions --  a comprehensive online guide to understanding the immune system, its anatomy, disorders, and other key information." Thyroid Disease Information - Hypothyroidism - Hyperthyroidism - Thyroid Cancer - Autoimmune Disease - Hashimoto's - Graves' - Goiter - Nodules - Metabolism - Weight Loss - Diet - Hormones - Hormonal Balance - Perimenopause - Menopause. About.com, n.d. Web. 3 Apr. 2012. <http://thyroid.about.com/library/immune/blimm02.htm>.