Katy Guest: My thighs are signalling it's breakfast time

Believe it or not, it does not always come naturally to me to salute Miley Cyrus, the shiny-haired, dazzly-toothed, singing, dancing American Dream. I am mildly offended by anyone that upbeat. Tenacious devotion to abstinence, God and the American way makes me nauseous. Her new song, "Fly on the Wall", is just plain sinister, appealing so transparently to the voyeuristic old perv element of her considerable fan base. But her tirade on behalf of justice and common sense last week made even a cynical old hag such as me warm to her.

Since these are the Noughties and Miley is 16, her blow for the sisterhood was obviously struck on a social networking site. Twitter, where ordinary folk go to "tweet" about their activities and get "followed" by people pretending to be Peaches Geldof, was the surprising forum for this feminist revolution. Its users may not know that this was a feminist revolution, but it was.

First, Miley wrote a tweet about her legs. "I just jiggled my thighs," she wrote, "and they shook on their own for 3 mississipis no more late night lucky charms." An innocent enough joke at her own expense, you might think. But soon everyone who wasn't rushing out to stockpile for the Lucky Charms breakfast cereal diet or heading on over to be a fly on her wall was posting on Miley's messageboard that she must be quite the little porker. Suddenly, no more Smiley Miley.

"talk all you want," she wrote. "i have my flaws. im a normal girl theres things about my body i would change but stop with calling me fat in post. i don't even like the word. those remarks that you hateful people use are fighting words." She went on in this spirit for some time before concluding: "oh and ps if your thighs don't jiggle go see a doctor. Thanks. :)"

In the brief interlude before Miley goes the way of almost all wholesome US pop sensations and turns into an emaciated amalgam of Britney Spears and the Olsen twins, I must quickly applaud her paean to jiggling. The vogue this summer for abbreviated clothing worn with matching eating disorders in a range of stylish colours must leave the fashion-conscious teenager mightily confused. On the one hand we have the Kids from Fame's less fun-loving younger sisters; on the other, Peaches Geldof is posing in Debenham's lingerie and boasting about her "achievable" figure. (Reader, my figure too is achievable, but relies on lamb jalfrezi.)

Unfortunately, Miley (whose alter egos include Hannah Montana and now Susie Orbach) was soon silenced by a new PC police – and had to apologise for disrespecting skinny people. "@nicolerichie has one of the tinniest most adorable bodies and i guarante u even HER thighs jiggle!" she wrote. Tiny, yes. Tinny, possibly. Adorable, not so much Miley. If Nicole Richie's thighs wobble, it is probably caused by rickets. She needs Lucky Charms and a lamb jalfrezi, fast.

I am relieved that the outbreak of sanity is over, because it does not sit well with me to admire Miley Cyrus. She needs to chip a tooth and grow a hairy mole or two before she can be any friend of mine. For now, watch sales of Lucky Charms soar as women attempt to emulate her figure. Let's face it, ladies: it's either that or it's God, abstinence and the American way.