She's supporting breast cancer awareness in the sexiest way possible.

Lisa Rinna is supporting a worthy cause in the sexiest way possible. Last week, the 57-year-old Real Housewives of Beverly Hills star posted photos of herself in her bra and underwear. In the caption, she reminded her followers that October is Breast Cancer Awareness Month and urged them to support a cancer research fund.

The feedback she got was super positive—not only for her breast cancer activism but also because of her age-defying six-pack abs, which the photos revealed.

“Both my Mom and my sister are breast cancer survivors," Rinna wrote, explaining that she has a personal connection to the disease.

Rinna then encouraged women to strip down and take their own underwear selfies to help fund breast cancer research. It's part of her partnership with The Kit Undergarments (she’s wearing them in her photos) and the company's #KitstoKickCancer initiative. For each Instagram selfie taken in their lingerie, the initiative donates money to the Women's Cancer Research Fund.

RELATED: Lisa Rinna Says Daughter Delilah Belle's Mental Health Issues Were Caused by a Childhood Infection

Rinna’s followers had plenty to say about her campaign—and the revealing posts.

“Breast cancer survivor here. Thanks for the awareness," wrote one. Another posed the question half the internet was probably wondering: “How do you look like that in your 50’s??”

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