Rachel Zoe weighs a dangerously thin 80 pounds, a doctor estimates to UsMagazine.com.
The celeb stylist, 38, showed off an emaciated figure while vacationing in St. Barts Thursday. She also Twittered that she’s battling bronchitis.
"When one is that thin and gets sick, it is incredibly easy to die, and not to be able to fight off any infection because there are no nutrients in the body to help her immune system,” says Dr. Fred Pescatore, who penned The Hamptons Diet.
"She looks like she has an eating disorder," continues Pescatore, who has not treated the Bravo reality show star. "One can see every rib and her arms are smaller than twigs."
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Pescatore says the dangers of being that thin for a prolonged period of time include stomach cancer, loss of teeth and hair, Osteoporosis -- and death.
Still, Zoe has long maintained that she is healthy despite her shrinking frame.
"Truthfully, I've never seen myself as being too thin," she has said. "Sometimes I'll look at photos and be like, 'Oh, that's not a good look.' But generally speaking, I'm not too thin."