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Jessica Simpson has slimmed down and is showing off.

“Too proud to sit down!! Behind the scenes of my new commercial. Thanks @weightwatchers,” tweeted the fashion entrepreneur on Saturday, along with a striking black-and-white picture in which she’s looking svelte (see right and below).

It was in a Weight Watchers video last month that Simpson revealed her plans to get married this year, motivating her to stay in shape.

Looks like she’s doing a pretty good job.