Michael Mosley and Mimi Spencer - The Fast Diet - The Original 5:2 Diet:Revised and updated -

The most popular diet this century
Daily Telegraph

The diet that has made even the sceptics sit up and listen
Sainsburys Magazine

Dieting has never been so delicious
Daily Mail

Fasting two days in seven isnt so hard, unlike the diets that need steely resolve 24/7
Express

The only diet youll ever need
Mail on Sunday

O n my first day as a medical student at the Royal Free Hospital School of Medicine, part of the University of London, I sat down with a hundred others in a huge lecture theatre to be greeted by the Dean. He talked for over an hour about how lucky we were to be there, our potentially glorious future and the importance of being kind to patients.

There are, however, two things he said that I still remember very clearly. The first was that, based on previous experience, four of us in that room would marry. He was right; I met my future wife that day.

The other thing he said which really struck me was that while we would learn an enormous amount over the first five years of our training, within ten years of graduating much of what we had learnt would be out of date.

Medicine and nutrition are disciplines in which the truth is constantly changing. New studies come along, sometimes reinforcing and sometimes undermining established wisdom. Unless you keep up with the latest research you are doomed to cling to outdated ideas.

It has been two years since we wrote the first edition of TheFast Diet and over that time a great deal has changed, so we decided it was time to update the book.

A number of new studies on intermittent fasting have been published and I wanted to include them. There are also important health areas which we didnt feel ready to include in the original book, but which we have been frequently asked about, including research into the effects of intermittent fasting on inflammatory diseases such as asthma, eczema and psoriasis.

We have included an enlarged section on exercise, as it is clear that combining exercise with intermittent fasting is likely to lead to greater improvements. There is also an interesting new study that has looked at the effects of combining intermittent fasting with a novel form of exercise, High Intensity Training.

Then theres the all-important question of what you should eat on your fasting days. Mimi has created a whole new range of tasty and satisfying recipes, together with plenty of useful tips on how to shop and cook to best suit your Fast Days.

She has also put together a new section looking at motivation, based in part on what those who have tried the diet have told us.

The original book has sold in over 42 countries, making intermittent fasting into a truly international phenomenon. Although there are many different forms of intermittent fasting (and we discuss most of them in this book), 5:2, a term which I used to describe my particular form (cutting your calories to a quarter for two days a week) is the one that people seem to find easiest to do and which has become the most firmly embedded in the national psyche.

Were told that 5:2 has been embraced by celebrities like Beyonc and Benedict Cumberbatch; it has become the diet of choice for government ministers, for the Chancellor of the Exchequer and the former Governor of the Bank of England; we have had messages of thanks from doctors, surgeons, parish priests, business leaders, sports teachers, school heads, politicians and a Nobel prize winner.

We set up a website (thefastdiet.co.uk) which is thriving and whose members support others who are thinking of trying intermittent fasting with helpful advice and tips. I have learnt a great deal from their experiences and questions.

The website contains thousands of success stories. These are a small sample:

I heard the author on a radio show and he made so much sense I tried the diet. I have never stayed on a diet before. I lost 40lb in a few months. It is six months later and the weight is still gone.

Ive now lost about 19lb in five weeks, my body fat is down from 37% to 33% and I can take my jeans off without undoing them and am happy to do so if anyone will watch!

My body shape has changed beyond recognition. My muffin top has gone and I have gained a waist instead! I have been doing this for 21 weeks and have lost 19lb, but also 3 off my waist, 3 off my hips, 2 off each thigh. My psoriasis has gone too. I am 42 and looking the best I have for 20 years.

Nothing works for everyone and some people have struggled to make it work for them. We include an updated troubleshooting Q&A section to offer some helpful pointers to maximise your chances of success.

In the first half of this book I delve into the science behind intermittent fasting. But one of the main reasons I think that the Fast Diet has been so successful is psychological. When you are on the 5:2 diet you arent on a constant treadmill, dieting all the time.

I certainly find it easier to resist the temptation to eat a bar of chocolate by saying to myself, I will have it tomorrow. Then tomorrow comes and maybe I eat it. But sometimes I dont.

Intermittent fasting also teaches you better ways of eating. If you follow our recipes and satisfy your hunger on fasting days by eating vegetables and good protein, then over time youll discover that when you get hungry you are more likely to crave the healthy stuff. As someone recently wrote to me: You dont get cravings, you dont spend money on special foods or programs. I lost more than 25lb and my husband lost more than 35lb. It was easy to do and we have maintained the weight loss, even over the holidays. I wish I had discovered this method 30 years ago.

The question I get asked most often is, not surprisingly, Are you still doing it? The answer is, yes and no. Back in the summer of 2012 I lost nearly 20lb (8kg), most of it fat, on the 5:2 diet. I also saw some spectacular improvements in things like my fasting glucose levels.

I didnt, however, want to go on losing weight, so I switched to doing mainly 6:1 (cutting my calories just one day a week). That, along with a regime of Fast Exercise (which I describe on pages last two years. Stable, that is, apart from Christmas and the occasional lapse.

I can honestly say I am in far better shape than I was two years ago and Im delighted so many other people can say the same.

Like me, Mimi is following a 6:1 protocol, and the weight she lost in the first six months of the Fast Diet (7kg) has stayed off for good. If theres a blow-out for birthdays or holidays, she turns the dial back up to 5:2 and soon gets back on track. One of her greatest joys is her fathers progress on the Fast Diet: after decades of being overweight, he lost over four stone in a single year an astounding, life-changing achievement. As he says, Its not like dieting at all; these days, I barely notice Im doing it. Since New Years Day, I can only remember being hungry once.