Researchers have sniffed out an unspoken rule among women when it comes to fragrances: Women don't buy perfume for other women, and they certainly don't share them.

Like boyfriends, current fragrance choices are hands off, forbidden--neither touch, nor smell. You can look, but that's all, says BYU industrial design professor and study coauthor Bryan Howell.

"Women treasure fragrances as a vital pillar of their personal identity," said Howell, who caught wind of the finding while researching fragrance-packaging preferences. "They may use the same fragrance for many years, and some women keep their fragrance choice a secret so their friends won't wear it."

For most women, the response to those findings is likely, well, duh, of course. Howell now freely admits that. Still, to have it blossom in an academic research experiment was surprising and fascinating--especially to his male colleagues, including lead author Hendrik Schifferstein of Delft University of Technology in the Netherlands.

According to the study, published in the journal Food Quality and Preference, women who do buy or share fragrances with other women choose fragrances they don't like themselves--or no longer value. Women in the study said gifting a friend with perfume might suggest they need to address a negative smell. Women prefer to avoid the possibility of negative connotations with friends and choose safer gifts instead.

"Buying perfume for another woman is like buying a swimsuit for someone else," said BYU campus news manager Emily Hellewell, who refused to reveal her perfume preference. "Swimsuits, like perfume choices, are very personal and it's not a gift you would give a friend."

BYU public relations major Ashley Lindenau also turned her nose up at the idea: "You wouldn't buy perfume you like for a friend because then they would smell like you. That's a little too creepy."

The study investigated fragrance-buying intentions of 146 women from the United States and the Netherlands. Although the researchers were primarily looking to see if consumers are more likely to buy fragrances with packages that are congruent with the product (they're not) the purchasing behavior of women towards women caught their eye.

Howell said the original statistical analysis appeared to say that women like to sabotage their best female friends when it comes scents.

"When women like a fragrances, they will purchase it for themselves or a male friend, but not for a female friend," Howell said. "When they dislike a scent, they won't purchase it for themselves or their boyfriend, but they will buy it for a female friend. It was a very strange finding so I had to go back and dig deeper."

Digging deeper included interviewing 12 female subjects to add qualitative layers to the research. Researchers, including undergraduate BYU student Drew Smith, not only learned why women don't buy perfume for other women, but they also discovered why women will buy fragrances for men.

"While women hold fragrances as personally intimate and respect other women's intimate choices, they happily want to influence what fragrances men wear," Howell said. "Assuming it is for a spouse or boyfriend, they want to pick fragrances they also like since they'll be around that person often."

Howell's research focuses on developing design methods to educate young student designers. His students, who have garnered attention for forward thinking bike helmet designs, outdoor equipment for females and many more products, work alongside him and other industrial design faculty to prepare for careers in product design.