It's well known that ads can be sexist; 'spin and grin' shampoo commercials and Protein World's ‘Beach Body Ready’ posters are prime examples. But new research has found that sexism is even more subtle than we might think. In reaction, Unilever has vowed to get rid of sexist stereotyping in its campaigns.

According to the world of online dating, coming across as an arse to some can make others love you more. If having haters makes those who like you like you all the more, does the same psychology apply to our relationships with brands? And does it actually pay for a brand to rub part of its audience up the wrong way?

Overflowing champagne bottles, foamy shower scenes, models in pillow fights. The sexy tactics used to flog products are well established. Yet with an increasingly feminist culture and studies showing that such imagery can impair our ability to remember what’s being advertised, does sex still sell?

Whether it’s a teenager’s intimate relationship with their iPhone, or a gleaming family heirloom designed by Rolex, building an emotional connection with customers is the holy grail for brands. But new research suggests that, actually, most brands are more likely to inspire indifference.