Studies in linguistic relativity have provided us with the insight that language affects the way we perceive the world. Our world view, in turn, influences our actions, which are reflected in the constructs we create around us, whether they be culture, social norms, or laws. In light of this theory, the presence of gender stereotypes in a language feature such as "man words" is not a purely linguistic, academic problem—it is a real problem whose consequences can be felt in the real world. We can get an idea of the nature of this problem if we look into the underlying meaning of "man words."
"Man bag" is one of the most widely used "man words" and its overt meaning is self-explanatory. The reason why the meaning is so obvious is that an existing word (handbag) is being used as the basis for a new word intended to be used for a men's equivalent of the same concept. The same structuring principle is used in other fashion-related "man words", such as "mankup," "manliner," (or “guyliner”) "manscara," "mantyhose," and the aforementioned "mankini." The consistent structure makes the surface meaning of these words immediately recognizable.
However, these words have an additional, more subtle meaning. Namely, the addition of "man" to the above fashion-oriented words implies that the original words are somehow inherently feminine and it takes the prefix "man" to linguistically neutralize them and, in a way, redeem them. But the implication goes even further. Objects such as handbags, pantyhose, and makeup are associated with fashion and beauty. Both of those categories are generally considered to be consumerist and not particularly profound. Even though this subtext may not be immediately obvious, when people repeatedly use or are exposed to these fashion-related man words, the implicit correlation between superficial consumerism and femininity gradually builds up in the unconscious. The "women=superficial consumers" stereotype gets entrenched in our minds. The presence of glaring stereotypes about women in the unconscious does leave a mark on our environment through the aesthetic standards, social norms, and expectations we create.
The damage caused by "man words" isn't limited to women. “Man words" also contribute to the negative stereotyping of men. The previously mentioned "man flu" is one such example. The Oxford Dictionary defines man flu as "a cold or similar minor ailment as experienced by a man who is regarded as exaggerating the severity of the symptoms." The idea here is that, deep down, men are really nothing but whiny attention-seeking weaklings who exaggerate their illnesses. But studies show that’s not true.
Research has shown that men are less likely than women to look after their health and seek medical attention when needed. According to the U.S. Agency for Healthcare Research and Quality, "men are 24 percent less likely than women to have visited a doctor within the past year and are 22 percent more likely to have neglected their cholesterol tests." Similar results have been reported in the U.K., where the National Pharmacy Association found that "men are much less likely than women to take advantage of primary care services, including community pharmacies. They are also unwilling to consult a pharmacist face-to-face or seek treatment when sick." This data makes the "man flu" joke fall decisively flat, and might make men even more reluctant to communicate their health problems for fear of being dismissed as needy hypochondriacs.