Archives for category: Smell


Could how heavy you are correlate to how strongly your brain reacts to the scent of bread wafting from a nearby bakery or backyard BBQ? Studies show that your senses (like smell and taste) react to inputs from the world around you, and not everyone’s neurobiological reactions are the same.

Despite decades of research, the truth is that scientists don’t exactly know why some people are overweight or obese, and some people aren’t. What we do know is that it’s not just about caloric intake, or activity level (though both do have some impact), and it’s not just about your genes. It’s mostly not about the type of food you eat, as carb-rich diets vs. protein-rich diets have generally been found to be equally unsuccessful for long-term weight loss (although processed foods — which tend to be carbs — definitely contribute to weight gain). And it’s not just about your psychology, or about how you were parented, though certainly family eating style is relevant.

It definitely *is* about how all of these things come together; calories in, activity level, metabolism as determined by genes, family eating, and brain chemistry.

All of which makes finding a ‘cure’ for obesity problematic. Rising levels of overweight kids and adults in the United States (and around the world; Northern and Western European countries both have rates of obesity around the same as ours) prove that nothing tried so far is working. And with chubby kids much more likely to grow up to become adults who are heavy, this is an issue that’s not going away.

But some studies point to the idea that different people deal with sensory inputs in various ways and may give us insight into some of the triggers of overeating, which is still at the heart of the issue for most overweight people.

An experiment at Maastricht University in The Netherlands shows us that there are some fundamental differences between overweight and normal-weight children’s caloric intake after exposure to the smell and taste of food. In the 2003 experiment, children were exposed to tasty smelling food for ten minutes, and then given food to eat; the normal weight kids tended to eat less than they would have if they hadn’t smelled the food first, which means they were at least partially satisfied just by enjoying the aroma of the food. On the other hand, the overweight kids actually ate more food after the exposure to delicious smells. The same went for if the kids were given a small snack beforehand.

What does this data mean?

You can read the rest of the text of this article over at Hypervocal.


Among my girlfriends, who are as a rule strong-minded and opinionated, and range from long-time wives and moms to freedom-loving creative types to serial monogamists, when the conversation turns to sex, we can all agree on one thing: We love the way our men smell, whether he is a two-time dalliance or a going-on-two-decades partner.

So much so that when our boyfriend/husband/long-term hookup is away from us, we like to keep a bit of something they wore around (or wear it ourselves); T-shirts are an almost-universal favorite. And this is not just silly pining — though surely the guys are missed — it has to do with the fact that smell conjures up more than just pleasant memories of the beloved.

For years, it wasn’t clear whether or not human beings produced (and responded to) pheromones, as we knew unequivocally that animals did. Pheromones are how most animals communicate their readiness to mate, as well as other information, and aren’t just ‘smells’ but specific chemical signals that are picked up by specialized receptors. Numerous studies over the last 15 years have proved that humans also exude and pick up on these signals (but we don’t ‘smell’ them in our nose, we process them in one of the oldest parts of our brain, the hypothalamus).

Not only do pheromones exist, but they are actually incredibly complex. Turns out that we can smell all kinds of details about someone, especially someone of the opposite sex (but only if we’re heterosexual; homosexuals generally respond to sex signals and information from members of their own sex).

According to ABC News: “Women’s hypothalami are activated when they smell the chemical similar to testosterone but not to the estrogen-like substance, whereas men’s hypothalami have the opposite response: They are turned on only by the estrogen-like chemical and not the testosterone-like one. There is also sexual disparity between the specific sub-regions of hypothalamus that are activated.”

One of the things we can smell on our partners — or even randoms that we get close enough to — is whether they have had sex recently. (Irresistibly attracted to that hottie next to you in yoga class? He may have just had a roll in the hay and neglected to shower). A Journal of Neuroscience study backs up what cuckolded spouses have long known: Humans emit specific pheromones when they have sex, and they can be detected. Take note, cheating partners:

Here, we use functional magnetic resonance imaging to show that the right orbitofrontal cortex, right fusiform cortex, and right hypothalamus respond to airborne natural human sexual sweat, indicating that this particular chemosensory compound is encoded holistically in the brain. Our findings provide neural evidence that socioemotional meanings, including the sexual ones, are conveyed in the human sweat.

To read the end of this article, click here!


According to Scientific American:

“A lot of communication in the animal world occurs via volatile, information-carrying “scent” chemicals, many of which remain to be chemically identified.

Generally speaking, pheromones are a type of infochemical used within a species to influence social behaviors and attract mates whereas kairomones send signals between different species and are often used to detect predators and prey.”

It makes sense that animals would emit and sense different scents interspecies vs. intraspecies, doesn’t it?