Silky straight hair has long been considered by many black women to be their crowning glory. So what if getting that look meant enduring the itchy burning that's a hallmark of many chemical straighteners. Or a pricey dependence on "creamy crack," as relaxers are sometimes jokingly called.

Getting "good hair" often means transforming one's tightly coiled roots; but it is also more freighted, for many African-American women and some men, than simply a choice about grooming. Straightening hair has been perceived as a way to be more acceptable to certain relatives, as well as to the white establishment.

"If your hair is relaxed, white people are relaxed," the comedian Paul Mooney, sporting an Afro, says in the documentary "Good Hair," which won a jury prize at the Sundance film festival and comes out in October. "If your hair is nappy, they're not happy." The movie, made by Chris Rock, explores the lengths black women go to get long, straightened locks, from a $1,000 weave on a teacher's salary to schoolgirls having their hair chemically relaxed. In the face of cultural pressure, the thinking goes, conformists relax their hair, and rebels have the courage not to. In some corners, relaxing one’s hair is even seen as wishing to be white.

"For black women, you're damned if you do, damned if you don't," said Ingrid Banks, an associate professor of black studies at the University of California at Santa Barbara. "If you've got straight hair, you're pegged as selling out. If you don't straighten your hair," she said, "you're seen as not practicing appropriate grooming practices."

Anyone who thought such preconceptions were outdated would have been reminded otherwise by some negative reactions to the president's 11-year-old daughter, Malia Obama, who wore her hair in twists while in Rome this summer. Commenters on the conservative blog Free Republic attacked her as unfit to represent America for stepping out unstraightened.