The #BeTheGirl​ weight loss challenge is being sponsored by Lopez's supplements company, BodyLab, and will run over 10 weeks

According to the challenge's promotional material, as obtained by Refinery 29, participants "will commit to a 10-week program with Jennifer Lopez as their inspiration and motivator along with a team of experts".

At the end of the challenge, the five "most successful" participants will win "a stay at one of Jennifer's favourite hotels, a luxurious spa treatment, and the chance to meet J.Lo herself".

(It's unclear how probable this "chance" of an audience with Lopez, 45, is.)

According to the challenge's promotional material, the "most successful" participants will be determined using a criteria that focuses equally on their physical and mental transformation.

The program promises to provide healthy and easy-to-make recipes, personalised fitness plans and expert nutritional advice, all of which is delivered through the #BeTheGirl​ free app.

While the app is free, the challenge is definitely not.

To sign up, participants are required to purchase one of BodyLab's​ weekly supplement programs, the cheapest of which retails for $US49 ($61) a week.

"I challenge you to crack the cocoon and find the butterfly; to love yourself more than anything on the menu," Lopez says in the challenge's promotional video.

Lopez's association with the challenge seems a bit odd, given the American Idol judge has often spoken publicly about the need for women to love their bodies as they are.

"When I first started on television [as a Fly Girl on In Living Color], people, and even my own manager at the time, would tell me I had to make all of these changes," she told Cosmopolitan for Latinas in October 2013.

"But you have to stand up and say, 'There's nothing wrong with me or my shape or who I am, you're the one with the problem!' And when you can really believe that, all of a sudden other people start believing too."