Jessica Simpson, Kourtney Kardashian & 8 Other Stars With Bad Hygiene

Jessica Simpson

The singer admitted to Ellen DeGeneres that she doesn't brush her teeth every day because she doesn't like when they feel "too slippery." Instead, she wipes them down with a shirt!

"I know it's gross but I always have fresh breath," she said. "It's really weird but I have great breath."

Kourtney Kardashian

The reality star refused to wear deodorant while breastfeeding Penelope on an episode of Keeping Up With the Kardashians.

"She reeks," said baby daddy, Scott Disick.

Robert Pattinson

During an interview with Extra, the 'Twilight' actor responded to rumors that stated he hadn't washed his hair in weeks.

"I don't really see the point in washing your hair, he said. "If you don't care if your hair's clean or not then why would you wash it?"

Cameron Diaz

"I don't believe in antiperspirant. It's really bad for you. I haven't used it for almost 20 years," the actress told E! News last April.

Matthew McConaughey

The actor himself admits he's not a fan of deodorant OR cologne.

"I don’t like to smell like someone or something else,” he told People. “Just like I don’t want a big name on the back of my jeans or a big label on my jacket. If [my smell] starts to bother someone, I'll take a shower.”

Shia LaBeouf

While filming Sia's music video for 'Elastic Heart,' 12-year-old dancer, Maddie Ziegler, admitted the actor smelled while on set.

"It was gross," she said.

Christina Aguilera

A reporter from Arena Magazine claims Christina once smelled like "a 12-year-old girl's bedroom on school-disco night."

Whatever that means…

Megan Fox

The sexy actress has admitted she doesn't exactly have the cleanest bathroom habits.

“I’m horrible to live with. I don’t clean. My clothes end up wherever I take them off. I forget to flush the toilet. Friends will tell me, 'Megan, you totally pinched a loaf in my toilet and didn’t flush,'" she said.

Brad Pitt

He's easy on the eyes, but not necessarily on the nose. The actor has been known to skip a shower as long as he has a baby wipe on hand.

Britney Spears

Although she sells perfume bottles with her name on it, Britney doesn't exactly have the best hygiene. The singer has been photographed walking barefoot in a gas station, for crying out loud.

Kim Kardashian

The reality TV star admitted that she rarely washes her hair.

"A sleek ponytail is one of my go-to looks at the moment. I usually wash my hair maybe every 3-5 days and on the third or fourth day I'll do a slicked-back ponytail," she said.