The Bulletproof Diet: Can drinking coffee with butter work?

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  • A diet popular with athletes and personal trainers, this diet is packed with healthy fats and coffee. We put it to the test...

    It sounds terrifying!

    This is the most serious plan of the bunch, and the one that many sportspeople and personal trainers follow. It’s based on high amounts of healthy fats, moderate portions of good-quality protein and tons of organic vegetables, all eaten at the right time of day to promote weight loss. There’s also the daily Bulletproof coffee – that’s a black coffee with butter in it.

    Gross. Who created it? 

    Tech billionaire Dave Asprey was trekking in the Himalayas, and was inspired by the yak butter drink the Sherpa guides had to fuel strenuous exercise. He started to investigate the relationship between biochemistry and human performance, and this diet is the result of that research.

    It’s strict, then?

    Yes. All your meat must come from grass-fed animals because, according to Asprey, industrially raised cattle have more toxins. Your healthy fats, veg, eggs and some fruit must be organic.

    What’s out?

    Alcohol, grains, legumes, pasteurised dairy, non-grass-fed meat, farmed seafood and anything sweet.

    Tester’s verdict:

    “At first, the idea of drinking a coffee “smoothie” of espresso, butter and MCT (that’s medium-chain triglyceride) oil for breakfast grossed me out, but it filled me up until lunch as it’s 600 calories. Cutting out sugar and booze helped to regulate my energy levels, too.”
    Lauren Smith, writer


    Eating a ‘clean’ (read non-processed and low-carb) diet of meat, fruit and veg aids speedy weight loss, and the coffee is quick and filling in the morning.


    Grass-fed meat and organic food is expensive, and the diet itself is a tad dull.

    How much was lost in three weeks?

    “It was hard-core, but I lost 7lb.”

    Get involved: The Bulletproof Diet (£18.99, Rodale Press In) or visit

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