Do pheromones control human attraction?

Could invisible chemical signals sway our behaviour, or who we're attracted to - all without us knowing?

- by HOLLY MCHUGH

The idea that humans might communicate through chemical signals called pheromones has captivated scientists and the public for decades, inspiring countless studies in search of proof. In animals, pheromones are well understood. Ants follow chemical trails to navigate and communicate, dogs mark their territory with scent signals, and moths release airborne pheromones to attract mates.

But whether humans do the same is trickier question. Could someone really trigger a physical or emotional reaction in another person without them even realising? Could it tip the scales of attraction? After more than 60 years of searching, the answer remains elusive – though new findings suggest we may finally be closing in on it.

FIRST WHIFFS
In 1959, Adolf Butenandt and his team discovered the first pheromone, bombykol, a chemical released by female silkworm moths to attract males. Soon after, scientists coined the term ‘pheromone’ to describe a chemical signal released by one individual that triggers a specific response in another member of the same species. The floodgates were then opened to hunt for human equivalents.

One of the first high-profile human pheromone claims came in 1971, when Martha McClintock published a study reporting that the menstrual cycles of 135 women in a university dormitory appeared to synchronise over the year. The phenomenon became known as the ‘McClintock effect’ and was widely claimed as evidence of a human pheromone. The finding crumbled under scrutiny, however, as other studies failed to replicate it and scientists showed that apparent synchrony can arise by chance.