It’s just hair isn’t it? Until what you are allowed to do with it – or not allowed to do with it – could get you killed.

In January this year, as Barack Obama was preparing to hand over his presidency, the US military reformed its grooming and appearance regulations for female soldiers allowing dreadlocks, cornrows and twists.

This may not sound like a big deal, but for black women whose “natural” hair naturally flouts military regulations failure to uphold grooming standards could result in disciplinary action. Yet taming their hair could also put them in danger.

This week US Vogue interviewed service women whose lives have changed dramatically due to the change in grooming regulations.

Major Tenille Woods Scott, a 12-year veteran, tells how straightening her hair while on active duty regularly put her at risk.

“In Iraq, I would relax my own hair every eight weeks, which was quite dangerous,” Woods Scott, who served in the region in 2007 and 2008, told Vogue. “In the hour or so that it took, I was nervous, thinking, What if a rocket or mortar comes in?”

Specialist Raissa Alexia Mbolo used to wake up at 4am every morning during her training to braid her hair in order for it to adhere to army regulations and says the new rules are empowering.

Captain Lakyra Pharms, who is in the US Marine Corps, had been straightening her hair for as long as she could remember before active duty in Korea meant she had no way to access a straightener. Her hair began to break off and she didn't even remember what her natural hair looked like. Now she favours textured twists, which she is allowed to wear.

Listen to Mia Freedman discuss Trump's Transgender ban in the military. (Post continues...)

This year  The New York Times spoke to Captain Danielle Roach. The 14-year veteran said she felt the grooming regulations were open to interpretation, which made many black women feel like "walking targets".

“It caused a lot of unnecessary stress. It was an exhausting 14 years,” Captain Roach said.

Imagine waking every morning and having to change something you were simply born with.

The US Army Times says there has been increasing disquiet that "the hair regulations put an undue burden on those with thick, coarse hair, forcing many women to spend time, money and discomfort on straightening or wigs if they didn't choose to chop it all off."

The January military grooming updates to women's hairstyles were buried in a directive that largely focused on changes to grooming to allow beards, hijabs and turbans due to religious reasons.

Even though the changes may have been hidden in the small print, they have made a huge difference to the lives of so many women in the US military.

For these women it isn't just hair. It's now their real hair.