Want to know the best new way to lose weight?

A double espresso blended to a thick froth with a tablespoon each of butter and coconut oil, it sounds like a heart attack in a cardboard cup. But the new research finding that fat is better for us than sugar means it is becoming popular with the body-conscious. What started as a diet fad in America is rapidly gaining ground in the UK.

Variously labelled ‘bullet coffee’ or ‘fat black’, a cup can be had at branches of trendy foodie store Planet Organic in London (‘Bullet Proof Coffee’ £2.55), or at outlets of juice chain Crussh, where it’s called ‘Smart Coffee’ (from £3.50). It’s also easy to make at home, with many recipes on the internet.

Fans are even drinking it as a meal substitute. They claim the combination of ingredients makes it the perfect breakfast-in-a-cup, giving you a prolonged energy hit, which sharpens your focus, burns calories, strips you of excess body fat and leaves you feeling full until lunchtime.

The downside is that the cloying texture makes it an acquired taste and those trying it for the first time often complain of nausea and diarrhoea.

The oily brew is the brainchild of U.S. entrepreneur Dave Asprey, who was served tea laced with yak butter when trekking in Tibet and became intrigued that mountain climbers use the drink for energy and sustained concentration. He went on to devise what he calls ‘the bullet-proof diet’ — a high-fat, low-carbohydrate regimen which, he claims, protects against fatigue, flab and chronic diseases, as well as promising dramatic weight loss.

The theory is that if you’re not filling your diet with carbohydrates (such as sugar, bread and pasta), your body will use fat as fuel instead. This is called ‘ketosis’. The ketogenic process is what makes Atkins and other low-carbohydrate diets work, but it is frowned upon by conventional weight-loss experts in this country, who say that low-carbohydrate diets can lead to headaches, muscle cramps, general weakness and digestive problems.

Butter coffee is central to the success of Asprey’s diet and he says the blend should combine organic coffee (he claims it’s toxins in ordinary coffee that give you the jitters) with grass-fed, unsalted butter (milk from grass-fed cows purportedly has health qualities superior to those of milk from grain-fed cows), and organic coconut oil.

The result is a thick, creamy coffee with a distinctly fatty, coconut aftertaste. And according to Planet Organic, which has been selling it for more than a year, its popularity is steadily growing.

(dailymail.co.uk)