Kim Kardashian has baffled top skin doctors by endorsing breast milk as a treatment for psoriasis.

The pregnant reality TV star has been struggling with the skin condition since 2011 and she recently got creative by stealing a bottle of her sibling Kourtney's breast milk to put on her legs as a soothing agent.

And during an episode of their hit TV show "Kourtney & Kim Take Miami," which aired on Sunday, the 32-year-old insisted rubbing milk on her legs helps calm the irritation.

She said, "These spots have been, like, really continuous - for, like, six months they haven't gone away - so the fact that they're white is a good sign. So I just want to keep on trying it."

And now Kim admits she can't wait to start breastfeeding her unborn baby - because any extra milk she produces will help her combat psoriasis.

Talking about the milk theft on Tuesday night's Jimmy Kimmel Live!, the mom-to-be said, "It was for a good cause. Do you know how much body make-up I have to put on just to cover up psoriasis... and she (Kourtney) produces enough (milk), trust me."

And she plans to use her own surplus breast milk to treat herself, adding, "Luckily I can try it on my own."

But skin experts aren't about to hand Kardashian a medical licence - instead they're concerned her milk methods will catch on.

Top doctor Vail Reese, who does not treat Kardashian, tells WENN, "This is the first I have heard about breast milk helping psoriasis. Anything that relieves dryness can minimise the itch and inflammation of this non-infectious disease and those afflicted with this condition can do well using over-the-counter moisturisers, particularly to wet skin, without having to ask nursing mothers for extra breast milk."

"I applaud Kim Kardashian for bringing attention to a condition that is so often hidden in unnecessary shame, but I worry that the business-oriented Kardashians might use this as an opportunity to market Kourtney's breast milk!"