Is fat friend or foe when it comes to weight loss? As the debate ignites again, Sarah Vine reveals how she lost half a stone in 10 days on a high fat diet

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I’ve had a few tellings off over the years from exasperated professionals trying to help me lose weight. But never before have I been told that I am not eating enough fat.

That’s right, fat. Cream cheese, avocados, walnuts: the kinds of foods that most diets tell you to stay well away from.

This time, though, I’m listening. Because in the ten days that I have been under the care of Zana Morris  at the Library Gym ,  I’ve lost an inch and a half on my tummy and seven whole pounds - four of those over the Easter weekend when not only was I not exercising, I was not being especially abstemious.

To me these seem like miraculous results. But to Zana, they are not as good as she would like. And it’s because I haven’t quite got my head around the vast amounts of previously forbidden foods that I need to be consuming.

The rest of the diet is easy. It’s not so much low GI  as NO GI. A typical breakfast would be two eggs with half a large avocado with a black coffee and a drop of double cream. Green vegetables, meat, oily fish - haddock, sardines, anchovies - and vast quantities of cream cheese also feature.

The aim is to eliminate all forms of sugar - whether through bad carbohydrate, lactose, gluten  or grains - so that my insulin levels flatline and instead of storing fat, my body is obliged to start using it up.

Some people, Zana says, are much more insulin responsive than others. In other words, very efficient at laying down fat stores. I am one of those lucky people. In the ice age, with food scarce and hard to find, I would have survived and thrived. In the 21st century, I’m just another middle-aged woman with middle-age spread.

And then there’s the exercise. If you, like me, loathe the clanking and groaning of the gymnasium, The Library will seem like a haven. And in any case, if by some strange chance you did not happen to like the relaxed, stylish environment, with its comfy sofas and stylish decor, you would at least be able to console yourself with the fact that you don’t have to spend much time there.

Workouts last 15 minutes.  A pretty intense 15 minutes, I’ll grant you, especially if trainer Sam happens to be in charge. But for someone like me, who normally has all the physical stamina of an anaemic sparrow, it’s perfect. A short, sharp burst of exertion, followed by a nice cup of tea and a sit-down.

So, to recap: seven pounds and an inch and a half. In 10 days. The easiest weight I have ever lost. Plus, I’m super energised - except for the evenings, when I can’t wait to hit the pillow.

This, though, is a good thing. Night time is sugar time for me. Glass or three of wine. Bit of chocolate. Maybe the odd Mini Magnum. But if I’m asleep before 10pm, there’s a limit to the amount of damage I can do in that respect.

In any case, since I’ve been on my high fat, no sugar regime , the cravings have subsided greatly. Not completely, of course. But if I just engage my brain before my mandibles, then I can stop myself.

Two more days to go, and I’ll be able to resume a more normal diet. Meanwhile, I’m off to tuck into the Boursin. Sans le pain or le vin, sadly. But that really would be too good to be true.

For more information about The High Fat Diet visit  Zana's website here .

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