The poster for the sports and nutrition store reads "Are you Beach Body Ready?"
Women have started vandalising the posters with sarcastic responses and changing the tagline.
We love London. Fuck patriarchy. pic.twitter.com/bDeET7pzdO— The Vagenda Team (@VagendaMagazine) April 22, 2015
Protein World's CEO Arjun Seth has replied to critics on Twitter saying they have "insecurities" and need to "grow up".
A petition has been set up by 19-year-old Charlotte Baring via Change.org to remove the posters. The petition currently has 44,124 signatures.
Baring said: "One thing that a lot of people have suggested is that the women who don’t like this campaign must be either fat, jealous or both: I quote, ‘a bunch of ugly jealous women’. Personally, I think this is irrelevant; my physical state shouldn’t interfere with my opinion. As it happens, I am happy with my body size and shape, and exercise regularly."
"That doesn’t mean I agree with body-shaming; it means I believe that everyone should be accepted for what and who they are. I also do not intend to target Protein World as a whole, although their recent social media responses have triggered a huge backlash, and many supporters of the petition have put this as their reason for signing. I am not trying to discredit their company, nor censor them. I am expressing the need for responsible advertising in order to change the perception of women in the media."