Wednesday, April 18, 2007

Smelling well

Smelling well is very important in modern society. We interact with hundreds of people each day, we smell them and they smell us. Smelling well is critical to our success in life. We are less likely to date or to hire people with bad smell. Most of us would avoid being treated by a dentist who has a bad odor.

Of all our senses, smell is the most mysterious. We can detect thousands of different odors, yet have trouble naming them. Although dogs are better sniffers than we are, the molecular receptors in our noses are remarkably sensitive. Certain molecules can be sensed and identified, even when they are surrounded by ten million molecules of regular air (or more!).

Smell is intimately related in our brains with memory. That is why a smell can sometimes evoke a distant memory from childhood that would otherwise be lost in the sands of time.

Smells are also intimately involved with our adult sexuality. Like other animals, we also judge potential mates by their body odor. Perhaps that is why, for thousands of years, we have been preoccupied with perfuming our bodies. Usually, for this purpose, we employ extracts of flowers (which are actually the sex organs of plants) or attractive odors from the scent glands of animals (musk). Perfumes are a multi-billion dollar business. Oddly enough, many of the aromas used in fragrances these days are synthetic, and are manufactured using petroleum as a starting point.

Natural body odor can be a sexual turn-on (I agree with Desmond Morris on this), but in modern "civilized" society, body odor (commonly referred to as "b.o.") is generally considered offensive. Most body odor comes from the armpits ("axilla"). In primitive society, molecules wafting from our armpits probably conveyed a variety of behavioral signals (we call such molecules 'pheromones'). Scientists are currently studying this subject, and have found that armpit secretions can modulate menstrual cycles in other women. They may also affect physiological properties and brain activity. So "b.o." may not be as bad as we think. Some scientists (myself included) think that the adult armpit is like a radio station, in which the axillary hairs are smell antennae that emit a variety of sexual and other messages that we may not even be aware of. Since the smell that each of us emits is unique and related to our wellbeing and genetic makeup (as with animals), our smell 'fingerprint' may help us identify suitable mates. It may also serve as an identification mechanism in the future. Most people (especially women, who smell better than men) can pick their mate's t-shirt out of a heap of clothing worn by strangers.

Most offensive odors are the product of microbial activity. Microbes cause bad breath, body odor, foot and shoe odor, wet towel odor, the stench of feces and sewage, and the smell of rotten food. Some scientists think that our aversion for these smells may be a primitive warning sign to avoid dangerous food and water, and to stay away from others with infectious diseases.

Our life experiences also conditions our smell preferences. We bond with our mothers by smell shortly after birth. We learn to love the odor of a good cheese, even when it smells like an open sewer. People who grew up on a farm, may even long for the odor of a barn or chicken coop.

Commercial companies know just how important smell is in our makeup. They turn scents into dollars by adding attractive fragrances to practically everything. They trick us into spending more money in supermarkets and malls, convince us that instant coffee is as good as the real thing, and even upgrade lousy whiskeys.

Smells, despite their great importance, are elusive. They don't have names like colors do. We say, "That smells like a …" And scientists around the world are still searching for that attractive molecule that will make us irresistible mating partners. Stay tuned, and keep on smelling.

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