Thousands of female users - and some male ones - began updating their statuses on Friday with “beige”, “hot pink”, “crimson red”, “sexy black and gold” or even “nothing”.

As online confusion raged and dozens of bloggers speculated about its meaning, it was disclosed it was part of a new campaign to help raise awareness for breast cancer.

Within hours of the craze starting, dozens of Facebook groups began appearing, with one group “breast cancer awareness ♥ I updated my Status with my Bra colour ♥”, having more than 33,000 fans.

The most popular colours appeared to be “white,” “black” and “beige”.

One blogger wrote: “Women everywhere are setting the bra colour they're wearing today as their Facebook status.

“The purpose is to promote breast cancer awareness, and remind women to get checked.

"The disease is very often curable if caught early enough.”

Another blog suggests the craze was started by women in Detroit, trying to raise awareness for the disease.

Andrea Rader, a spokeswoman for the Susan G. Komen for the Cure foundation, said the group was not behind the campaign.

She called it but called it "a terrific tool for raising awareness."

She added, "We just hope people act on it — get educated, get a mammogram."

Malorie Lucich, a spokeswoman for Facebook, said she was not sure where or how the craze started.

But she said it was an example of a “grass-roots” movement beginning on the social networking site.

"What is particularly unique about this grass-roots campaign is that it seems to have been started by a user or group of users, as opposed to an official entity, and spread virally throughout Facebook," she told CNN.

"It's an ideal example of how an individual voice can be magnified to create awareness for a good cause and ignite action among millions by using a site like Facebook."

Although no fund raising is involved in this campaign, it has been a landmark in viral marketing. The campaign has served as a fast, free and fun way for women to raise awareness about breast cancer and remind other women to get themselves examined.

The campaign has been such a phenomenal success that it is currently the 33rd most popular search on Google in the past hour. We expect this campaign to soon become a top trending topic on Twitter as well.

Charities and non-profits have previously used Facebook to create awareness for social causes and generate funds, however, this campaign suggests the ingenuity in which social media marketing could be used to send messages across the globe and impact behaviors and force actions.

There is one silver lining in this campaign as well, that needs to be touched. The campaign has marked the first successful use of Facebook status updates with very few words to send a powerful message across. If this becomes the norm, and other facebook users started to use short status updates to convey informational, marketing or news worthy messages (which is exactly what Twitter was supposed to do) – well then Twitter would surely have to run for its money. Watch out twitter, Facebook users might just start using Facebook for tweeting as well.