He made the 5:2 diet popular and his new Fast 800 plan features meal replacement shakes for the first time. Here’s how Dr Michael Mosley went from a shake skeptic to advocating 200 calorie smoothies

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The meal replacement shake seems like a very 1980s diet culture throwback, and in terms of off-the-shelf artificial options, Dr Michael Mosley  still believes that’s the case, but he’s changed his views on drinking your calories rather than eating them in his latest take on intermittent fasting . In his newly published  Fast 800 plan , he’s included recipes for 200 calorie homemade smoothies to replace occasional meals, telling You magazine  that, despite his previous reservations “they can have a place when you’re on a diet. They’re convenient, easy and can help your way into the Fast 800.”

As far as benefits of meal replacements shakes go, Dr Mosley states that they’re useful as they reduce the effort and planning involved in cooking and preparing meals while providing “a decent amount of vitamins and other essential nutrients.” His Fast 800 shake recipes include healthy fats to promote satiety and absorption of vitamins and he’s convinced that introducing the odd shake could result in “a reduction in cravings.”

Dr Mosley isn’t endorsing any old blend - he emphasises that for meal replacement shakes to have a a place in a weight loss programme they need to be “fairly low in carbs, contain plenty of protein, enough fat and decent amounts of fibre  to keep you feeling full and encourage fat burning.” Dr Mosley isn’t promoting meal replacement shakes as a long-term measure or a daily go-to either - he thinks that they should be used as a “reboot rather than a way of life" and only be consumed if you have a significant amount of weight to lose, ideally as advised or under the supervision of a medical or dietary expert.

The science, including an Oxford University study showing that an 800 calorie soup and shake plan resulted in greater weight loss in obese patients than a ‘slow and steady’ approach, convinces him that they can aid rapid weight loss but that, even if you’re following his 800 calorie a day plan, you need to base your intake around wholefoods rather than living by the Nutribullet.

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