A new health trend sees the health and fitness conscious putting butter in their coffee before their workouts. But why? Peta Bee investigates

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How do you take your coffee - white, with a sweetener or sugar, or strong and black with a dollop of butter? In a trend that is sweeping the coffee shops of America and starting to creep into java joints here in the UK, the butter option is increasingly likely to be the choice of the supremely health and fitness conscious.

Enthusiasts say that adding around 80 grams of butter or coconut oil to your cuppa not only gives a performance-enhancing energy boost, but can rev up your brainpower and, remarkably, even help you to lose weight.

What sounds like an unlikely combo has attracted followers of the paleo diet  - the ‘caveman’ style nutritional plan focused on eating animal proteins and fats  - as well as the CrossFit training brigade and top endurance athletes. Former Olympic coach and cyclist, Dave Smith, has been tweeting about how helpful he finds his buttery coffee habit for fuelling his gruelling bike rides. And Dave Asprey, a Silicon Valley entrepreneur, claims he increased his IQ by more than 20 points, lowered his biological age and lost 100 pounds in weight through the butter-enhanced drink that also contains a supplemental mix of medium chain triglycerides (MCTs), the beneficial fatty acids found in coconut oil, that he has now marketed as ‘Bulletproof coffee’. A cup of it will, Asprey claims, pep up your energy levels “for up to six hours if you need it,” as well as “shrinking your waistline” in the process.

Too good to be true or a worthy craze? Miguel Toribio-Mateas, chairman of the British Association for Applied Nutrition and Nutritional Therapy, is a fan of the practice but says it is nothing new. In fact, butter has been added to drinks for centuries in some parts of the world. Ethiopians add butter to their coffee and in Singapore coffee beans are stir-fried with butter in a wok before being strained through a filter into your cup. Order a cup of morning tea in Tibet, for example, and the ingredients are likely to be butter, tea, and salt or black pepper. Asprey says it was while trekking in the Tibetan mountains that he first encountered the strange beverage mixture. “I staggered into a guesthouse from the 10-degree weather and was literally rejuvenated by a creamy cup of yak butter tea,” he writes on his website .

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So how does it work? Adding up to 200 calories of fat to your coffee will undoubtedly leave you feeling fuller. But that’s not all. Black coffee has long been a favourite energy booster for endurance athletes like runners and cyclists. Researchers at the Australian Institute of Sport (AIS) were among the first to show how cyclists who sipped one to two cups of coffee before and during exercise were able to keep pedaling for longer and faster than those who took plain water.

A little of the black stuff could also increase fat-burning during exercise, studies have shown. Caffeine contains substances that stimulate the release of fats into the bloodstream. Those fats are immediately used to fuel exercise before the body reverts to its limited carbohydrate stores to keep going. Adding butter or coconut palm oil enhances the effect, prompting the body to rely on fat instead of carbohydrates for fuel. “In short, the caffeine in the coffee will give you a nice energy boost and it is prolonged by the fat content in the butter,” says Toribio-Mateas.

Connoisseurs are keen to stress that not any old butter will do. “The trick is to make sure your butter is from grass-fed animals as it contains the largest amounts of conjugated linoleic acid (CLA), proven to support energy and help with weight loss,” says Toribio-Mateas. “If you just buy cheap and nasty non-organic, non grass-fed butter, you'll be putting lots of pesticides and environmental toxins into your body. That just defeats the objective.”

Grass-fed butter and compressed oils of palms and coconut are also rich in MCTs that are digested more quickly than other fats, meaning they are more readily available for energy. “MCTs are a great source of ‘natural energy’ as they bypass normal fat metabolism,” says Toribio-Mateas. “It is crucial to choose raw, organic coconut oil for optimum effect.”

There are downsides, of course. Adding 100-200 calories to your cuppa is an advantage only if you are active. More fat won’t help your weight loss efforts if you sit down all day. But a fitness routine might benefit from a buttery cup of the black stuff. For taste reasons, unsalted butter is obviously a better choice - among the most popular is a product like the naturally organic Beurre D'Isigny, from maritime pastures in Normandy. Having tried it, I can vouch that it is unusually creamy, but not unpleasantly so. A coffee fan, I plan to stick with my new addition as a pre-workout fix, even if the boost it provides is nothing more than a psychological gain.

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