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It's no secret that Gwyneth Paltrow is a fan of diet and exercise trends -- but one that she tried in her 20s came at a high cost: "hallucinating after 10 days."

"I've done juice cleanses in the past, and in my 20s, I did the Master Cleanse, which left me hallucinating after 10 days," she admitted in a column she penned for the UK's Telegraph. "Be aware: a juice detox can crash your metabolism and lead to future weight gain."

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The Goop founder dished out that helpful piece of advice and more for the paper on Monday. According to the mother-of-two (to kids Apple, 9, and Moses, 7, with husband Chris Martin, 36), it's also more productive to measure weight loss in inches, not pounds.

"There is something punitive about weighing yourself," she wrote. "It can leave you vulnerable to shame and guilt, and it messes with you psychologically. Women naturally gain and lose weight during their monthly cycle anyway, so it can be more realistic to monitor your body shape with a measuring tape."

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This isn't the first time the lifestyle guru has offered her unsolicited advice to fans. Paltrow, 40, also recently chatted with British Cosmopolitan about her take on aging and Botox.

"I don't like Botox. I think on some faces it works, but it's when you can really see it that it start to look fake," she said. "I love how French actresses age but don't really do anything about it -- it's beautiful."

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Paltrow instead prefers to stay fit with a regular workout routine -- the Tracy Anderson Method -- and a balanced diet, with the occasional cheat.

"Allow yourself programmed treats -- I often have a glass of red wine in the evening and smoke a cigarette on a Saturday," she advised readers in the Telegraph column. "I love those moments because they are just the right amount of naughty."

"That balance keeps you vibrant," she concluded. "You have to live your life, after all."


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