Miley Cyrus has argued her stomach “has a brain”.

The singer-and-actress is known for showing off a slim physique, thanks to exercise and a healthy diet.

However, the 20-year-old indulged in some fast food today and promptly told her Twitter followers that her stomach couldn’t cope.

“I now remember why I never eat pizza. It makes me feel like sh*t. #glutenized,” she posted.

“Let me clarify "sh*t" wasn't meaning "fat" I mean sick. Because gluten is poisoning me. Your stomach has a brain too & it hates SH*T food (sic).”

Among her favourite keep-fit methods are jogging and Pilates, with the star often spotted out and about in her gym clothes.

It looks like she will be stepping up her exercise routine to compensate for her pizza binge.

“...back on the health train tomorrow. #cheatnight,” she wrote.

“Ate to much pizza and French fries. Yoga and a swim in the a.m. (sic)”

It doesn’t look like Miley has too much to worry about when it comes to her figure.

The former Hannah Montana star and her fiancé Liam Hemsworth enjoyed a romantic holiday in Costa Rica earlier this month and both look toned as they cuddle up on the beach in their swimsuits.

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