Let's be honest: we all have a few guilty habits that we struggle to give up.
And that applies to movie stars, musicians, and models as much as the rest of us.
Just because they look perfect on TV doesn't mean they have everything figured out. These 11 bad habits still plague some of Hollywood's biggest stars.
Maybe seeing the effect they have on them will convince you to quit once and for all.
1. Nail biting
Pop star Britney Spears has struggled with nail biting since childhood, and was once spotted with bleeding nails on the set of X-Factor.
But this is more than just nasty habit - experts compare this tic to psychological conditions like obsessive compulsive disorder.
If you're hoping to quit, start by tackling the causes of stress and anxiety in your life. Then track when and why you nibble your nails.
2. Hormone injections
Suzanne Somers is one of the many celebrities who admits to taking a daily cocktail of pills and hormones to look and feel younger.
The Three's Company star confessed to starting her day with estrogen creams and hormone injections, before taking 40 pills mixed into a shake.
To top it off, Somers says she took another 20 pills at night.
Oprah Winfrey is another fan of these treatments, but experts say they do more harm than good. If you're not careful, hormone injections can promote diabetes, high blood pressure, and joint pain.
3. Binge drinking
Sadly, many young Hollywood stars have struggled with alcohol dependency.
After finding fame as the lead in the Harry Potter movies, Daniel Radcliffe says he was "a recluse" by age 20 because of his addiction.
"The drinking was unhealthy and damaging to my body and my social life," he said in an interview.
While Radcliffe was able to get clean, other stars weren't so lucky.
Jon Hamm split with his longtime girlfriend in 2015 after a stint in rehab, proving that even movie stars don't have it easy.
4. Crash diets
We all know that stars have to work out nonstop and watch what they eat to stay in perfect shape. But there are safe and seriously unsafe ways to shed the pounds.
Beyonce was definitely putting herself at risk when she took the Master Cleanse to prepare for her role in Dreamgirls.
The diet limited her meals to lemon juice, maple syrup, cayenne pepper and water. She lost 20 pounds, but was lucky to stay out of the hospital.
Meanwhile, the Kardashians have endorsed diuretic tea, Gwyneth Paltrow promotes juice cleanses, and Shailene Woodley ate clay to get in shape.
5. Anger management
Plenty of stars have been caught flipping out on camera, including the embarrassing moment when Reese Witherspoon asked a police officer, "Do you know my name?"
But Hollywood sometimes rewards celebrities for this bad behavior.
After years of lashing out at his costars and mistreating his partners, Charlie Sheen was given a starring role in a sitcom called... Anger Management.
In recent years, Kanye West has also lashed out at the paparazzi. The rapper was put on probation and sentenced to anger management after a particularly nasty fight.
6. Plastic surgery obsession
While the late, great Joan Rivers was the most famous example of a star who tried (and failed) to update their look, there are just as many vain men in Hollywood.
Country legend Kenny Rogers complained that a botched eyelid lift "drives me crazy."
"I'm not happy about it," he revealed to People.
Mickey Rourke, an '80s heartthrob, also bears the telltale signs of cosmetic surgery. A facelift seems to have pulled away his sideburns.
And Carrot Top, the famous prop comedian, is almost unrecognizable after years of skin treatments and facial surgeries.
7. Sleep deprivation
Here's a surprising trend that strikes more celebrities than average folks: exhaustion.
A laundry list of celebrities including Justin Bieber, Lindsay Lohan, Selena Gomez, Demi Moore, and Dave Chapelle have been sent to the hospital for severe fatigue.
Rihanna even shared a photo of herself hooked up to an IV the morning after partying at the Met Gala in 2012.
Busy shooting schedules, the hectic LA lifestyle, and substance abuse could all play a part in the epidemic of celebrity exhaustion.
The public is slowly catching on to the fact that tanning machines are dangerous, but many celebrities still depend on them to maintain their sun-kissed looks.
One of the worst offenders is Simon Cowell, who has a private tanning salon in his own home which includes a tanning bed and a smaller machine for his face.
The dangerous dose of UV rays from tanning machines has been linked to skin cancer.
9. Taking drugs
While some celebrities are upfront about their drug use, others battled addiction in secret for years.
Jamie Lee Curtis was hooked on painkillers, Macauley Culkin was arrested for possession of Xanax and marijuana, and Robert Downey Jr. was caught sampling just about everything before he finally went sober.
Drew Barrymore is one of the most tragic cases of all. After finding fame as a child star, the actress says she became a teenage addict.
It took an intervention from Crosby Stills and Nash guitarist David Crosby before Barrymore finally cleaned up her act.
10. Junk food
Yes, the stars are just like us, and many of them have been spotted snacking on something sweet or greasy.
But sometimes they take their love of unhealthy food a little too far.
Selene Gomez also blamed a 2011 hospital stay on being "malnourished" because of her junk food obsession.
The pop singer says she can't resist M&Ms, Kit Kats, Snickers bars, and Goobers, and depends on her mother to mind her diet.
In 2018 no one can say they don't know the risks of smoking. But a few movie stars are still waiting on their reality check.
An embarrassingly long list of stars, including Katherine Heigl, Keira Knightley, Keanu Reeves, and Brad Pitt have been spotted with a cigarette in hand.
One of this year's most concerning celebrity transformations was Ben Affleck's. Once a Hollywood heartthrob (and one half of Bennifer), today Affleck is almost always spotted with a cigarette or vape pen.
Add in his worrying weight gain and an embarrassing phoenix tattoo, and it's easy to see why fans were concerned about Affleck.
Thankfully, the tattoo was for a movie. But we're still waiting for you to drop the cigs, Ben!
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