Sara De Boer / Retna Ltd. 1 / 3
Sara De Boer / Retna Ltd. 1 / 3

Miley Cyrus may be a globe-trotting Disney superstar worth millions, but she's also a 16-year-old girl, and, like all 16-year-old girls, she has certain insecurities. But her decision to share one of them with her 600,000-plus Twitter followers has given her an unwelcome glimpse of the Internet's scary, self-image-stomping underbelly.

"I just jiggled my thighs and they shook on their own for 3 Mississippis," she wrote on Friday. "No more late night Lucky Charms."

Miley's critical self-assessment -- and her vow to give up her magically delicious midnight snack food -- is something we've all been guilty of from time to time. In her case, however, there's proof that she was unnecessarily harsh on herself.

The next day, she was the epitome of a healthy, athletic teen as paparazzi snapped her frolicking on a beach in the Bahamas (it was a working vacation -- she performed that night) in a hot-pink-and-black string bikini.

RELATED: More recent photos of Miley's bikini bod

But her Tweet opened the floodgates across various message boards for some seriously off-target types who were only too happy to agree and elaborate on her fault-finding, even stooping to using the f-word (no, the other one -- "fat").

"Talk all you want. I have my flaws," Miley fired back. "I'm a normal girl. There's things about my body I would change but stop with calling me f*t in post[s]. I don't even like the word. Those remarks that you hateful people use are fighting words. The ones that scar people and cause them to do damage to themselves or others."

Cyrus then offered her advice for "people that are so okay with being so hateful," suggesting they "spend [less] time on a gossip website and more time a. reading your bible b. reading stories/articles about what happens when cyber abuse and name calling happens. Kids hurt themselves."

RELATED: See more hot stars in bikinis.

She also attempted a little damage control by pointing out, "Oh and P.S: If your thighs don't jiggle go see a doctor," which further riled up the masses, who accused her of dissing the skinny demographic.

That prompted Miley to note that Nicole Richie, who's currently incubating her second child, "has one the tiniest, most adorable bodies and I guarantee u even HER thighs jiggle! Everyone's do!!! I'm not putting skinny girls down! I believe in exercise and treating your body like a temple."

RELATED: Check out Nicole Richie and more celeb moms.

But she must have thought better of holding Nicole up as a gam-shaking example, because she sent a message her way, saying, "We still gotta get our McMuffins . . . U r beautiful!"

Richie was a good sport about the kerfuffle, responding with a photo that will haunt your dreams for days to come.

"Speak for yourself!" she jokingly told Cyrus from beneath a bikini-clad bodybuilder. "Maybe you haven't seen a picture of me recently. Don't be jealous."

Speaking of jealousy, that's the reason Cyrus' 20-year-old beau Justin Gaston cited as he assured her that she shouldn't let the haters get her down.

RELATED: See Miley and Justin, plus more celebs on Spring Break.

"I think you're the most beautiful girl in the world," he gushingly Twittered. "Don't listen to mean people -- they're just jealous."

NEXT: The High Cost of Being Britney