Black women’s hair was already a hot topic on blogs and talk shows before Gabby Douglas vaulted onto the world stage at the London Olympics. Then the rhetoric really started to sizzle, like a straightening comb on the back of your neck.

After some viewers complained on Twitter that Douglas’s hair looked unkempt, social media and the blogosphere erupted with incredulous condemnation of those shallow enough to focus on the 16-year-old’s coiffure vs. her graceful jumps and powerful twists.

And Douglas’s gold medal-winning performance Thursday in the gymnastics individual all-around did not silence the haters, who were still atwitter on Twitter.

“This little girl just won a gold medal and is representing her country, and people are talking about her edges? Really?” said Demetria L. Lucas in an interview Friday. Lucas’s memoir, “A Belle in Brooklyn,” chronicles the fun and frustration of life as a single black woman.

Earlier in the week, right after the cyber-heckling began with Douglas’s first performance, Lucas came to her defense on “You really want her sitting up in the Olympic Village thinking about a hot comb or some lye right now, with all that’s on the line?”

Apparently, some people did.

“Why hasn’t anyone tried to fix Gabby Douglas’ hair?” sniped one on Twitter.

Another huffed: “gabby douglas gotta do something with this hair! these clips and this brown gel residue aint it?”

Hair as a cultural and political statement has long been a sensitive subject of debate among black people. Thanks to social media and Douglas’s stunning achievement of becoming the first black woman to win the Olympic gymnastics women’s individual all-around competition, the family spat has spilled into a public forum, generating coverage from news organizations around the world. Some black people are shaking their heads about the focus on Douglas’s hair; some white people are scratching their heads because they don’t know why her tresses have caught the attention of the hair patrol in the first place.

In the 1960s, when African Americans were implored to be proud of their dark skin and natural hair, black women sported afros — short and sassy or big and billowy. Since the 1990s, young African Americans have rocked dreadlocks and braids, which are particularly popular among artists. Straightened hair, however, has never gone out of style and continues to draw criticism from those who say it is an attempt by black people to mimic the texture of white women’s hair. But for many black women, straight, perfectly styled hair is a shield against a society that doesn’t appreciate afro-centric features. Black women’s obsession with straight hair and weaves was the subject of the much-talked-about 2009 documentary “Good Hair” by comedian Chris Rock.

Now, black women are in the midst of another natural-hair revolution, with many abandoning chemical straighteners, or relaxers, in favor of natural hair — from simple afros to springy, gel-enhanced curls and twists. The movement is a popular subject of discussion on talk shows and has spawned several blogs and Web sites. This week, the media was abuzz over Oprah Winfrey showing off her natural tresses on the cover of the September issue of her magazine.

Sisters need to relax. It shouldn’t matter how black women wear their hair. But it does, says Tina Opie, an assistant professor of management at Babson College in Wellesley, Mass., because “hair is identity.” For black women who “see hair as a signifier of identity — of class, ethnicity, of gender — it matters. So when these black women see Gabby Douglas wearing her hair in a way they see as sub-par, they view it as a threat, something that will negatively impact how others view them as well. She’s a representative of the collective,” Opie said.

Opie says this undermines the argument that the haters are themselves self-hating, as some observers have suggested. “If they didn’t care about being black women, they wouldn’t care about how she looks. What they’re saying is, ‘Listen, Gabby, you’re on the international stage representing us, so do it well!’ ”

But, Opie says, the women who cringe at the sight of Douglas’s frizzy edges and kinky kitchen (translation: the tight, curled hair at the nape of the neck) need to ask themselves: “Does her hair trump her performance? She’s won two gold medals and for the discussion to be about her hair as opposed to the great honor she’s bestowing on African Americans and the United States, I think we really have to ask ourselves: Why?”

One of the best retorts to those who seem to have gotten themselves all tangled up over Douglas’s hair was this gem on Twitter from @AmandaMarcotte: “If you want to ride Gabby Douglas for her hair, you should be open to her coming over to critique your muscle tone.”