In less than a month, Pippa Middleton will marry her fiancé James Matthews — and she's ramping up her pre-wedding diet and fitness routine at full force.
According to E! News, Middleton was spotted leaving a 75-minute Pilates class at KX Gym, a fancy fitness center in London. While an hour and 15 minutes of Pilates may sound exhausting, keep in mind she's a super badass endurance athlete — so we're thinking she could handle it.
In addition to breaking a sweat, E! News says Middleton is also a big fan of the Sirtfood Diet, a food program of 20 specific foods rich in sirtuins, which, according to new research, can increase your metabolism and enhance your body's fat-burning ability.
The Sirtfood Diet, which has made waves on social media as of late, is divided into two phases spread out over the course of three weeks. During phase one, you're allowed three Sirtfood green juices and one Sirtfood-rich meal per day, totaling 1,000 calories. For the next four days, you're allowed two Sirtfood green juices and two Sirtfood-rich meals per day, totaling 1,500 calories.
Phase two lasts for the final two weeks and is basically just maintenance, allowing three Sirtfood-rich meals and one Sirtfood green juice daily.
If 1,000 calories a day seems crazy low to you, that's because it is! While we've already debunked the Sirtfood Diet for ourselves, it's good to hear it from experts as well.
The Cut talked to registered dietitian Brigitte Zeitlin, who says that even though by nature you will probably lose weight on the plan, you will most likely gain all that weight back (and then some) once you stop abiding by the Sirtfood Diet's rules.
"It's unhealthy and unsafe to eat below 1,200 calories a day," Zeitlin said. "In addition to not giving yourself the proper energy and nutrients you need each day you're on this fad diet, eventually you're going to go off of it. You're going to gain all of the weight you lost back, and more often than not, you're going to gain even more weight back."
Plus, Middleton's hobbies include hardcore workouts, which require more fuel than just 1,000 calories and a limited list of foods. All in all, yo-yo dieting is dangerous and ineffective in the long run. If you're getting ready for your own wedding day like Pippa, just stick to a clean diet and plenty of exercise.
[H/T Getty / Anthony Harvey / Stringer]
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