Kim Kardashian has shown off her newly trim body on Twitter to advertise a US weight loss product.

The curvy star posted pictures of herself posing in skimpy bikinis, and swears her svelte shape is down to the diet pills she's being paid to pimp out.

Kim Tweeted: "I lost my last 6lbs fast & toned up! Loving Quick Trim."

In case we haven't got the message, she added: "Quick Trim does a body good!"

Despite Kim's glowing endorsement and stunning figure, Quick Trim is yet to be approved by the U.S. Food and Drug Administration, the independent body responsible for regulating such products.

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