CELEBRITY
11/26/2013 12:01 pm ET

How Kelly Osbourne Dropped 70 Pounds, And Kept The Weight Off

Jon Kopaloff via Getty Images

Ever since Kelly Osbourne began her weight-loss journey in 2009, the "Fashion Police" star has embraced some wacky methods to drop a whopping 70 pounds: everything from calorie-burning hula-hoop parties to following the Reverse Diet (eating pizza for breakfast and oatmeal for dinner). Now she’s Hollywood’s poster girl for a U.K. weight loss craze called the mushroom diet, aka the M-Plan, touted as a way to shed pounds without losing your curves. After Osbourne's success, superstar Katy Perry also got on board, giving the diet a major buzz boost when she tweeted about it recently while shedding 15 pounds.

The M-Plan calls for replacing lunch or dinner each day with a mainly mushroom dish for two weeks, resulting in a loss of four to 10 pounds. Skeptics abound –- Perry's own trainer, Harley Pasternak, tells Life & Style he opposes single-food diets and is “giving her a hard time about it” -– but nutrition experts tout mushrooms as a great meat substitute at a fraction of the calories (only 25 per cup).

“They’re high in protein and fiber, helping you feel fuller longer,” says mind-body wellness expert Peggy Hall, creator of 52 weeks of weightloss.com. Additionally, ’shrooms are satisfying because “they taste meaty, so it doesn’t feel like you’re just eating a pile of lettuce leaves,” explains registered dietitian Dr. Wendy Bazilian.

For more on Kelly and Katy's new weight loss program, head over to lifeandstylemag.com and pick up the new issue of Life & Style, on newsstands now.

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