As emotions go, happiness usually hides in plain sight: seen in a broad smile, heard in a raucous laugh, felt in a big hug.

But new research suggests there may be a less obvious way to pick up on another person’s positive vibes: smell.

According to a team of European researchers, happiness may generate chemicals that get secreted in sweat, and that sweat signal gets sniffed by those around us.

The experiments also suggest that we not only breathe in the upbeat emotions of others, but by doing so we actually become happier ourselves.

“Human sweat produced when a person is happy induces a state similar to happiness in somebody who inhales this odor,” said study co-author Gun Semin, a research professor in the department of psychology at Koc University in Istanbul, Turkey, and the Instituto Superior de Psicologia Aplicada in Lisbon, Portugal.

The findings were published recently in Psychological Science.

The researchers noted that prior research has already demonstrated that negative emotions, such as fear or disgust, can be communicated via odors in sweat.

To see whether the same holds true for the happier feelings, Semin’s team gathered sweat samples from 12 young men after each watched videos designed to induce a variety of emotions, including happiness and fear. All the men were healthy, drug-free nonsmokers, and none drank, consumed smelly foods or engaged in sexual activity during the study period.

In turn, 36 equally healthy young women were engaged to smell the samples while their reactions were monitored. The smell group, explained investigators, was confined to women because women typically have a better sense of smell than men and are also more sensitive to emotional signaling.

After analyzing the facial expressions of the smell group, the research team concluded that there does, in fact, appear to be a so-called “behavioral synchronization” between a sweating person’s emotional state, the sweat generated, and the reaction of the person who sniffs that sweat.

Specifically, that meant that the faces of women who smelled “happy sweat” displayed facial muscle activity deemed to be representative of happiness.

source: http://www.webmd.com/