Gwyneth Paltrow has shocked fans by revealing she has taken illegal party drug ecstasy.

The Iron Man star, whose Goop website is dedicated to healthy living, made the revelation during an appearance on U.S. Tv show Watch What Happens Live when host Andy Cohen asked her a series of personal questions as part of his Plead The Fifth segment.

Guests are allowed to skip one out of three questions, and Paltrow chose to answer when Cohen asked her, "What is the hardest drug you've ever taken?"

Paltrow replied, "Ecstasy" without elaborating.

The actress is mother to two young children, Apple and Moses, with her estranged husband Chris Martin.

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