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The Fast 800: How to Combine Rapid Weight Loss and Intermittent Fasting for Long-Term Health
Six years ago, Dr Michael Mosley started a health revolution with the 5:2 Fast Diet, telling the world about the incredible power of intermittent fasting. In this audiobook he brings together all the latest science - including a new Time Restricted Eating - to create an easy-to-follow programme.
Recent studies have shown that 800 calories is the magic number when it comes to successful dieting - it’s an amount high enough to be manageable but low enough to speed weight loss and trigger a range of desirable metabolic changes.
The secret of this new programme is that it is highly flexible - depending on your goals, you can choose how intensively you want to do it.
Along with an accompanying PDF featuring delicious, low-carb, Mediterranean-style recipes and menu plans by Dr Clare Bailey, The Fast 800 offers an effective way to help you lose weight, improve mood and reduce blood pressure, inflammation and blood sugars. Take your future health into your own hands.
PLEASE When you purchase this title, the accompanying reference material will be available in your Library section along with the audio on our Desktop Site.
Recent studies have shown that 800 calories is the magic number when it comes to successful dieting - it’s an amount high enough to be manageable but low enough to speed weight loss and trigger a range of desirable metabolic changes.
The secret of this new programme is that it is highly flexible - depending on your goals, you can choose how intensively you want to do it.
Along with an accompanying PDF featuring delicious, low-carb, Mediterranean-style recipes and menu plans by Dr Clare Bailey, The Fast 800 offers an effective way to help you lose weight, improve mood and reduce blood pressure, inflammation and blood sugars. Take your future health into your own hands.
PLEASE When you purchase this title, the accompanying reference material will be available in your Library section along with the audio on our Desktop Site.
262 pages, Kindle Edition
First published December 27, 2018
2680 people are currently reading
2554 people want to read
About the author
Michael Mosley
256 books307 followersMichael Mosley was a British television journalist, producer, and presenter who worked for the BBC (amongst other broadcasters) from 1985 until his death in 2024. He was probably best known as a presenter of television documentaries on biology and medicine, and his regular appearances on The One Show.
Born in Kolkata, India, the son of a bank director, Mosley studied philosophy, politics and economics at New College, Oxford, before working for two years as a banker in the City of London. He then decided to move into medicine, intending to become a psychiatrist, studying at the Royal Free Hospital Medical School (now part of UCL Medical School).
Becoming disillusioned by psychiatry, upon graduation Mosley joined a trainee assistant producer scheme at the BBC in 1985. Since then he produced and presented many documentaries on science and/or medicine. He was an advocate of intermittent fasting and low-carbohydrate diets who wrote books promoting the ketogenic diet.
Mosley died on the Greek island of Symi on 5 June 2024.
Born in Kolkata, India, the son of a bank director, Mosley studied philosophy, politics and economics at New College, Oxford, before working for two years as a banker in the City of London. He then decided to move into medicine, intending to become a psychiatrist, studying at the Royal Free Hospital Medical School (now part of UCL Medical School).
Becoming disillusioned by psychiatry, upon graduation Mosley joined a trainee assistant producer scheme at the BBC in 1985. Since then he produced and presented many documentaries on science and/or medicine. He was an advocate of intermittent fasting and low-carbohydrate diets who wrote books promoting the ketogenic diet.
Mosley died on the Greek island of Symi on 5 June 2024.
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Displaying 1 - 30 of 327 reviews
October 4, 2022
Re-read 3th - 4th October 2022.
It’s been 3 years since I last read this book. And a lot has happened in that time. I’ve had breast cancer, a mastectomy, chemo and radiotherapy. And I’m struggling a little with the meds I’m on plus I need to lose some weight. So it’s back to this eating plan for me now.
I’ve re-read and decided I’m going to try the TRE with a mainly Mediterranean diet and take it from there.
#### UPDATE 29th DECEMBER 2019 ####
This diet has become a way of life for me.
I aim to have 5 diet days a week. And when I started that was the case. This is because I have lunch plans every Tuesday and Thursday. On these “off” days I eat and drink whatever I like.
Obviously other things come up and some weeks I end up with only two diet days. It depends on what’s happening. I no longer get hung up on these days. I’ve been doing the diet long enough now that I don’t seem to put weight on even on really bad weeks. This doesn’t include holidays. But I’ve found that two weeks back on my plan and I lose all the holiday weight anyway. This gives me the freedom to have two weeks off at a time and not worry about my weight. I truly can enjoy my holidays I just accept that on the Monday after I’m back on the plan.
The plan for me involves eating between 1200 and 1500 kcals on my diet days. I eat good food and make all my calories count. Because my “off” days are just that. I have whatever I want and as much as I want.
You may be wondering (if you’ve made it this far) why 800 kcals isn’t enough yet I did the 500 kcal 4:3 diet perfectly well on and off for years. That’s because with the 4:3 I’d split my days. I never did consecutive days which made it easier. But when I started this my first week I had fri, sat, sun and mon on 800 kcals. Monday night I was so hungry I felt weak and fatigued and realised that 800 kcals just wasn’t enough for me. Initially increased it to 1000 temporarily but I was still losing weight. I wanted to keep my metabolism up and found I was losing weight on 1200 to 1500 kcals so this is what I stick to.
I started this diet on the 24th June 2019. And I just can’t praise it enough. It was the right diet at the right time.
When I first started I stuck to the 800 kcals. I soon discovered this wasn’t enough (more on this at the end). Over the months I’ve adapted this to suit and I now have the perfect diet for me.
I’ve lost 31lbs in 6 months and after the first couple of weeks it was easy. This includes 3 holidays and more meals and nights out than I can count. Losing weight is all about finding the right diet for you and this is it for me.
While I may not follow the book exactly as it’s written. My diet today is a result of this and there’s no going back.
Original review.
The 5:2 or in my case the 4:3 diet has worked really well over the last couple of years. It’s the only diet I’ve found that allows me to lose weight but still have a social life.
While the 500 days are hard the results make it worth it. It’s a shame I don’t do it all the time. Life gets in the way usually in the form of holidays and then I’m gone. It’s then a case of getting back on track which gets pushed back. You know how it is.
I was intrigued when I noticed this book. Mainly because 800 calories sounds a whole lot better than 500.
This book is well written, clear and simple to read. Examples and data are given to back everything up.
This book really is the best of all worlds.
It explains the advantages of following an 800 calorie diet. How you can fit it into a 5:2 if that works better for you. It also covers the TRE (time restricted eating).
This was the right book at the right time for me. I’m now following an 800 calorie 2:5 or 3:4 diet (depending on what’s happening certain weeks). I’m also using the 14:10 or 16:8 (all calories are consumed with a 10 or 8 hour period) TRE.
This book was fabulous.
I voluntarily read a review copy kindly provided by NetGalley.
October 8, 2019
I first became aware of Intermittent Fasting or the 5:2 diet a few years ago when a few friends were enthusiastically describing the benefits of it. I tried it without doing any reading, and barely managed the first day because I was just too hungry. Inspired to try again by someone who is roughly my height & size and had lost 5kg fairly quickly, I gave it a go, and quickly worked out for myself the major new modification in Mosley’s plan - that 500 is too few calories for most people but 800 is much more manageable. Over a year I lost 12kg, taking me from a BMI of just over 25 to the weight I was in my early 20s, a happy UK size 12, which I had not enjoyed since the Atkins diet 15 years earlier.
Unfortunately, like all diets, when you stop them, weight returns, and a combination of events, including two frozen shoulders, led me to regain more than half my lost kg over a year, and lose the motivation to tolerate hunger. I am still doing a modified 5:2 but cheating much more often than I should. When I saw a copy of The Fast 800 Diet for request on NetGalley, this seemed a good opportunity to try again by doing it properly. I’m interested in the science behind it and reassured that Mosley is a qualified medical doctor, albeit non-practising since he has spent most of his career in journalism/broadcasting.
The Fast 800 is written in a clear engaging style with a mix of personal anecdotes and opinions, reviews of relevant research and suggestions on how to combat common pitfalls. The principal ideas from the 2012 original - The Fast Diet - have not changed, and he begins by explaining the theories around how fasting affects the body’s metabolism, in particular with regard to insulin and it’s effects on appetite and fat storage. Mosley’s own story includes the diagnosis of type 2 diabetes which kicked off his interest in the first place, and how his almost evangelical enthusiasm for the benefits of his discoveries was triggered by the remission of his diabetes. His gleeful confessions about his own chocolate addiction help make him more relatable than your typical preachy celebrity nutritionist. A second book, The 8-week Blood Sugar Diet, was aimed specifically at patients with diabetes.
In the intervening years, large population studies have been done which support his theories, and this is what led him to update the plan and publish the new book. The key change, as mentioned, is that the magic number is now 800 calories, which is both safer and more manageable for most people. The new principle is Time Restricted Eating, (TRE), which means limiting food in take to only part of the day - he proposes 16 hours initially - so not eating after 8pm and before 8am, then reducing that interval to 12 or even 10 hours, which is not as difficult as it sounds. He’s a big fan of the Mediterranean diet, which makes sense as there is good evidence that consuming mostly plants, protein (including meat, oily fish and pulses) and lashings of olive oil is the key to heart health and longevity.
The first chapter explains the reasons behind the modern obesity and secondary diabetes epidemics, and stresses that obesity is not the patient’s fault because the combination of genes and environment make it almost inevitable. Mosley has a way of revealing facts that seem completely obvious but that had never occurred to me before - for example that we think we’re addicted to sugar, but that no one tucks into a bowl of pure sugar; it’s actually the combination of carbohydrate and fat in a 2 to 1 ratio that makes our favourite foods so compelling.
Subsequent chapters focus on the medical benefits of fasting and TRE, and then of rapid initial weight loss - which counters the long-established theory that slow and steady is the way to go - because of the psychological boost that rapid and noticeable change brings. He then explains the Med Diet in detail, and goes on to extol the virtues of exercise in complementing his plan, and advice on the role of stress in poor eating and how to combat it. The remaining chapters deal with the practical aspects of how to begin, who should be excluded, and common Q&As and pitfalls, while the second half is all sample recipes and suggested meal plans. This part is where the average wannabe dieter’s interest may wane: no matter how delicious salmon, kale and leafy greens are, the list of foods to be avoided - realistically forever if you want to keep the weight off - is daunting. I can live without cakes and biscuits but avoiding rice and bread is miserably hard.
I read this as an ebook and so had the usual surprise when you get to 80% and discover the rest is all just references, so the book is shorter and therefore more readable than expected.
My main criticisms is that considering that the author is British, all units are imperial - presumably for the American market - I can’t think in lbs and have no idea what a quart is.
He also promotes meal-replacement shakes and refers to his website for brand suggestions - but in fact the site only promotes their own brand which seem quite expensive. I would rather be able to easily buy small quantities from a supermarket or service station when needed, to be able to try out flavours than order a months worth of shakes which might be revolting. One of the major difficulties of a diet like this is finding suitable foods on the go - since consuming large amounts of fruit is not recommended, nuts are really only a snack and most snack bars are full of sugar.
Overall I would recommend this book to anyone looking for a new way to lose weight - I do intend to start over once I get home from my current travels, as I have lots of lovely new clothes bought to celebrate my previous new shape that are now uncomfortably tight, and this has given me plenty of new ideas on how to do it properly - and the reassurance that when you get it right, those ravenous hunger pangs will settle quite quickly.
My thanks to NetGalley for the arc in exchange for an honest review. The Fast 800 Diet is published on 24th December - timely for all those New Year resolutions?
Unfortunately, like all diets, when you stop them, weight returns, and a combination of events, including two frozen shoulders, led me to regain more than half my lost kg over a year, and lose the motivation to tolerate hunger. I am still doing a modified 5:2 but cheating much more often than I should. When I saw a copy of The Fast 800 Diet for request on NetGalley, this seemed a good opportunity to try again by doing it properly. I’m interested in the science behind it and reassured that Mosley is a qualified medical doctor, albeit non-practising since he has spent most of his career in journalism/broadcasting.
The Fast 800 is written in a clear engaging style with a mix of personal anecdotes and opinions, reviews of relevant research and suggestions on how to combat common pitfalls. The principal ideas from the 2012 original - The Fast Diet - have not changed, and he begins by explaining the theories around how fasting affects the body’s metabolism, in particular with regard to insulin and it’s effects on appetite and fat storage. Mosley’s own story includes the diagnosis of type 2 diabetes which kicked off his interest in the first place, and how his almost evangelical enthusiasm for the benefits of his discoveries was triggered by the remission of his diabetes. His gleeful confessions about his own chocolate addiction help make him more relatable than your typical preachy celebrity nutritionist. A second book, The 8-week Blood Sugar Diet, was aimed specifically at patients with diabetes.
In the intervening years, large population studies have been done which support his theories, and this is what led him to update the plan and publish the new book. The key change, as mentioned, is that the magic number is now 800 calories, which is both safer and more manageable for most people. The new principle is Time Restricted Eating, (TRE), which means limiting food in take to only part of the day - he proposes 16 hours initially - so not eating after 8pm and before 8am, then reducing that interval to 12 or even 10 hours, which is not as difficult as it sounds. He’s a big fan of the Mediterranean diet, which makes sense as there is good evidence that consuming mostly plants, protein (including meat, oily fish and pulses) and lashings of olive oil is the key to heart health and longevity.
The first chapter explains the reasons behind the modern obesity and secondary diabetes epidemics, and stresses that obesity is not the patient’s fault because the combination of genes and environment make it almost inevitable. Mosley has a way of revealing facts that seem completely obvious but that had never occurred to me before - for example that we think we’re addicted to sugar, but that no one tucks into a bowl of pure sugar; it’s actually the combination of carbohydrate and fat in a 2 to 1 ratio that makes our favourite foods so compelling.
Subsequent chapters focus on the medical benefits of fasting and TRE, and then of rapid initial weight loss - which counters the long-established theory that slow and steady is the way to go - because of the psychological boost that rapid and noticeable change brings. He then explains the Med Diet in detail, and goes on to extol the virtues of exercise in complementing his plan, and advice on the role of stress in poor eating and how to combat it. The remaining chapters deal with the practical aspects of how to begin, who should be excluded, and common Q&As and pitfalls, while the second half is all sample recipes and suggested meal plans. This part is where the average wannabe dieter’s interest may wane: no matter how delicious salmon, kale and leafy greens are, the list of foods to be avoided - realistically forever if you want to keep the weight off - is daunting. I can live without cakes and biscuits but avoiding rice and bread is miserably hard.
I read this as an ebook and so had the usual surprise when you get to 80% and discover the rest is all just references, so the book is shorter and therefore more readable than expected.
My main criticisms is that considering that the author is British, all units are imperial - presumably for the American market - I can’t think in lbs and have no idea what a quart is.
He also promotes meal-replacement shakes and refers to his website for brand suggestions - but in fact the site only promotes their own brand which seem quite expensive. I would rather be able to easily buy small quantities from a supermarket or service station when needed, to be able to try out flavours than order a months worth of shakes which might be revolting. One of the major difficulties of a diet like this is finding suitable foods on the go - since consuming large amounts of fruit is not recommended, nuts are really only a snack and most snack bars are full of sugar.
Overall I would recommend this book to anyone looking for a new way to lose weight - I do intend to start over once I get home from my current travels, as I have lots of lovely new clothes bought to celebrate my previous new shape that are now uncomfortably tight, and this has given me plenty of new ideas on how to do it properly - and the reassurance that when you get it right, those ravenous hunger pangs will settle quite quickly.
My thanks to NetGalley for the arc in exchange for an honest review. The Fast 800 Diet is published on 24th December - timely for all those New Year resolutions?
March 10, 2024
At least Michael Mosley practices what he preaches. Once again, he cheerfully takes on a combination of two of his most successful health and food manuals - the 5.2 and the 800 calories a day - and provides diligent reports on his successes and failures.
If you can adapt this to suit your daily lifestyle - and, most importantly, your metabolism - this method really works. Fasting isn’t for everyone but I find it essential to maintain both clarity and focus for optimum output in my work, exercise and study habits. Try it for yourself and hopefully you’ll agree.
If you can adapt this to suit your daily lifestyle - and, most importantly, your metabolism - this method really works. Fasting isn’t for everyone but I find it essential to maintain both clarity and focus for optimum output in my work, exercise and study habits. Try it for yourself and hopefully you’ll agree.
December 5, 2019
Dieting revisited!
A combination of ideas put forward about food, exercise and losing weight by Mosley are ringing bells with me. Particulars he's mentioning are factors my doctor has been raising with me. Although my need is more to do with excess weight putting pressure on my arthritic knees.
The book is pithy, easy to read, not too complicated in its explanations, fairly straightforward and most importantly, held my interest.
The things that struck me most included:
that Mosley gives "a number of options so you can tailor the program to your needs, goals and motivation...based on 800-calorie fast days—it’s high enough to be manageable and sustainable but low enough to trigger a range of desirable metabolic changes." So changing metabolism gets a tick and there are Options available for the way you might approach the process. 800 calories is really not a hardship for me but alas there goes the glass of a particularly nice Sauvignon Blanc I've just purchased.
Some of the Benefits which also resonate for my particular needs are:
1. Better sleep
2. Cutting risk of type 2 Diabetes
Mosley references the idea of Intermittent fasting such as the 5:2 program alongside Time Restricted Eating which apparently helps with acid reflux (another little quirk I've developed.)
He does address the concerns about rapid weight loss equaling rapid weight gain and then it seems morphs into championing a Mediterranean type diet to counteract this.
Sadly I do know about foods that convert to sugar. (But between the knowing and doing I find there's a ginormous gap!)
He discusses Exercise. Once again there is a certain amount of symmetry with what Mosley puts forward and what my doctor's been saying. His hints for strength training are a plus. I liked his "12 ways to introduce more activity into your life" section. Using the exercise bike is one cross over, although my days of stomach crunches and squats have long gone. Tai Chi and water aerobics is more where I'm centered these days.
The chapter on Stress was a bonus, especially with the inclusion of practicing Mindfulness and a couple of short related exercises.
The Recipe section suggestions I feel would be easily incorporated into one's routine. Interestingly gluten free (such a buzziword--is mentioned only once, and then in a recipe.)
As with all food control books the things on the NO list are what we all know about (no pun intended).
So there goes the Hagen Daz and Lindt and that rather delicious Savy B.
But wait maybe some of those can be incorporated on a Five day day! If I go for a 5:2 regime!
Despite what seems to be many pluses, I will say I am reserving judgement about the validity of Mosley's ideas for me until I can explore them further. Which for my particular needs could well be a good thing.
An Atria ARC via NetGalley
A combination of ideas put forward about food, exercise and losing weight by Mosley are ringing bells with me. Particulars he's mentioning are factors my doctor has been raising with me. Although my need is more to do with excess weight putting pressure on my arthritic knees.
The book is pithy, easy to read, not too complicated in its explanations, fairly straightforward and most importantly, held my interest.
The things that struck me most included:
that Mosley gives "a number of options so you can tailor the program to your needs, goals and motivation...based on 800-calorie fast days—it’s high enough to be manageable and sustainable but low enough to trigger a range of desirable metabolic changes." So changing metabolism gets a tick and there are Options available for the way you might approach the process. 800 calories is really not a hardship for me but alas there goes the glass of a particularly nice Sauvignon Blanc I've just purchased.
Some of the Benefits which also resonate for my particular needs are:
1. Better sleep
2. Cutting risk of type 2 Diabetes
Mosley references the idea of Intermittent fasting such as the 5:2 program alongside Time Restricted Eating which apparently helps with acid reflux (another little quirk I've developed.)
He does address the concerns about rapid weight loss equaling rapid weight gain and then it seems morphs into championing a Mediterranean type diet to counteract this.
Sadly I do know about foods that convert to sugar. (But between the knowing and doing I find there's a ginormous gap!)
He discusses Exercise. Once again there is a certain amount of symmetry with what Mosley puts forward and what my doctor's been saying. His hints for strength training are a plus. I liked his "12 ways to introduce more activity into your life" section. Using the exercise bike is one cross over, although my days of stomach crunches and squats have long gone. Tai Chi and water aerobics is more where I'm centered these days.
The chapter on Stress was a bonus, especially with the inclusion of practicing Mindfulness and a couple of short related exercises.
The Recipe section suggestions I feel would be easily incorporated into one's routine. Interestingly gluten free (such a buzziword--is mentioned only once, and then in a recipe.)
As with all food control books the things on the NO list are what we all know about (no pun intended).
So there goes the Hagen Daz and Lindt and that rather delicious Savy B.
But wait maybe some of those can be incorporated on a Five day day! If I go for a 5:2 regime!
Despite what seems to be many pluses, I will say I am reserving judgement about the validity of Mosley's ideas for me until I can explore them further. Which for my particular needs could well be a good thing.
An Atria ARC via NetGalley
July 12, 2019
I saw the BBC documentary a while back and was fascinated by the theory and successes of the 5:2 diet so had to have a read of the updated Fast800 Diet.
The in depth explanations and the science behind intermittent fasting along with the health benefits definitely gave me food for thought (pardon the pun, ha!). If I'm honest, I feel I got more out of the first half of the book, though for those starting out with dieting the recipes and exercise advice would prove useful.
Arc provided by Netgalley for review
The in depth explanations and the science behind intermittent fasting along with the health benefits definitely gave me food for thought (pardon the pun, ha!). If I'm honest, I feel I got more out of the first half of the book, though for those starting out with dieting the recipes and exercise advice would prove useful.
Arc provided by Netgalley for review
January 20, 2019
I liked the fact it was all updated but when you re read 5:2 from 2012 you see just how much the advice has changed which is a bit disconcerting- how do we ever know we are following the best advice? So 2012 was all ‘just fast for 2 days and eat whatever you want for the other 5’ (which never worked for me) and ‘low calorie does not work for people and science has proved people put it all back on in the long term ‘and now it’s all ‘very low calorie is the way to go as the quick results inspire you’ and people do keep the weight off.
All very odd.
However, there is some consistent advice in here which is always going to be good (keep a break between food, extend time between dinner and breakfast, eat for your gut). Recipes are also great.
It just feels like it was written in a hurry. And you are regularly advised to go on the new website but you see that it costs £99 to sign up which just seems excessive.
All very odd.
However, there is some consistent advice in here which is always going to be good (keep a break between food, extend time between dinner and breakfast, eat for your gut). Recipes are also great.
It just feels like it was written in a hurry. And you are regularly advised to go on the new website but you see that it costs £99 to sign up which just seems excessive.
February 4, 2019
This book is in every bookstore window here in Melbourne. I saw Mosley interviewed on a local TV show and thought he had some really good ideas. This books seems to be some re-hashing of things I've read elsewhere. Nevertheless, I'm trying the regimen and will report back.
November 21, 2019
In 2015, I did 5:2 and lost about 15 pounds. I stopped doing the diet and gained back the weight in two years. I lost the weight at the same slow rate as I have on any other diet (WW, Atkins, arbitrary calorie limitation). Back then, time-restricted eating wasn't a big thing but I quickly realized that if I was going to limit to 500 calories I had to put off eating as long as possible. Since I've gained the weight back and read tons of diet and nutrition books, I've come to the conclusion that all diets work, the only really hard part is maintenance. I actually think this is a diet I could stay on forever this time because it only requires Mediterranean-style eating once you reach goal weight and if you don't stop weighing yourself, you can correct small weight gains very quickly.
I like this diet because 1) based on all my reading, it is the most scientifically up-to-date, 2) it's free to implement it, 3) I find it very empowering to be able to skip breakfast and do very low-calorie days but also to be able to easily take days off, 4) I think I might be able to maintain this new form. I advise you to take every single thing he says very seriously though. I even have a friend-support group this time.
I like this diet because 1) based on all my reading, it is the most scientifically up-to-date, 2) it's free to implement it, 3) I find it very empowering to be able to skip breakfast and do very low-calorie days but also to be able to easily take days off, 4) I think I might be able to maintain this new form. I advise you to take every single thing he says very seriously though. I even have a friend-support group this time.
January 25, 2019
I love a good Michael Moseley book. Well researched, simple to understand and backed up by science there are so many gems in this book.
July 9, 2019
Clearly and convincingly sets out the scientific research which (assuming it’s true) can help you maximise your health – Time Restricted Eating, Intermittent Fasting and HIIT. I don’t think it works so well as a ‘diet book’ – the recipes and menus are too limited – but that’s not why I read it anyway.
Thanks to NetGalley and the publisher for this ARC.
Thanks to NetGalley and the publisher for this ARC.
April 8, 2019
This is not a great book.
(But it's still better than his first one.)
It mainly teaches people how to lose weight by doing a very low-calorie diet (800 kcal per day).
It suggests you start eating only 800 kcal every day, and then move to doing it twice per week.
And it incorporates time-restricted feeding to the mix.
I'm not even sure why I read it.
(But it's still better than his first one.)
It mainly teaches people how to lose weight by doing a very low-calorie diet (800 kcal per day).
It suggests you start eating only 800 kcal every day, and then move to doing it twice per week.
And it incorporates time-restricted feeding to the mix.
I'm not even sure why I read it.
March 17, 2019
Motivating!
My View:
Dr Michael Mosley delivers another powerful and informative, motivating read, that introduces us to recent science based theories on managing your health that he has personally explored. I like his personable approach, his willingness to put his body on the line in the name of medical research is commendable.
As always, the writing here is accessible, the data/evidence presented in clear and concise ways that make choosing good health a realistic outcome. TRE (Time Restricted Eating) IF (Intermittent Fasting) are something that we are going to hear a lot more about in mainstream medicine and Dr Mosley succinctly explains how using these methods, in a responsible way, we can trigger a range of metabolic changes that will improve our health.
Fascinating reading.
My View:
Dr Michael Mosley delivers another powerful and informative, motivating read, that introduces us to recent science based theories on managing your health that he has personally explored. I like his personable approach, his willingness to put his body on the line in the name of medical research is commendable.
As always, the writing here is accessible, the data/evidence presented in clear and concise ways that make choosing good health a realistic outcome. TRE (Time Restricted Eating) IF (Intermittent Fasting) are something that we are going to hear a lot more about in mainstream medicine and Dr Mosley succinctly explains how using these methods, in a responsible way, we can trigger a range of metabolic changes that will improve our health.
Fascinating reading.
February 6, 2019
This is a life transforming book, it’ll cure you!
Easy to follow and backed up by the best research, I found it highly motivating and a really interesting read.
Easy to follow and backed up by the best research, I found it highly motivating and a really interesting read.
August 11, 2019
Thank you to Netgalley and the publisher for providing this book in exchange for an honest review.
This is an excellent book on the different types of intermittent fasting and a couple of different diets. Dr Mosley does an great job explaining various studies that back up his teachings. He also explains how these options can reverse diseases and overall improve health, not just for weight loss.
This is an excellent book on the different types of intermittent fasting and a couple of different diets. Dr Mosley does an great job explaining various studies that back up his teachings. He also explains how these options can reverse diseases and overall improve health, not just for weight loss.
November 14, 2024
I like that he backs up his claims with studies humans participated in and provides examples. As someone insulin resistant who did an 800 diet before with excellent results and didn’t know how to maintain, this was motivating and helpful.
August 20, 2020
This is a very easy to read book, filled with research, useful tips, evidence and recipes. It's an update/re-write on Mosley's 5:2 diet book. Chapters include one on why we put on weight in the first place - and it's not as simple as 'eat more than we need' - there are decades of past diet advice and food industry motivations to overcome. The book is based around a healthy mediterranean diet (not the pizza and pasta!) filled with fish and fresh vegetables. Activity is also important but you don't have to join a gym - walking or riding an exercise bike are great. There are many recipes and meal plans included. And the best thing - I've started to put it into practise!!
August 4, 2025
Began this book a few weeks ago and forgot to add it!
It’s a very good insight into what excessive weight can do to your body. It can even cause snoring which was true in my case. I’ve never been very big but I had began to feel it in my clothes and when walking the dog k was puffing more. I never realised how much a few extra kilos had impacted my health. If wasn’t until after I’d lost 10 kgs and our 6 year old granddaughter stays the night and said “you don’t snore anymore Grandma”. I asked my husband and he said it was true.
Extra weight can impact joints and many other issues so as a sufferer of rheumatoid arthritis and fibromyalgia I needed to do something. This and other books by Dr Moseley (and his son Dr Hack Moseley and his wife Dr Gail Bailey) have helped me get back on track after lapsing during winter here in South Australia. I knew I had gained almost half of what I’d lost over 4 months ago the so now I’m back on track to my goal weight again.
It’s a very good insight into what excessive weight can do to your body. It can even cause snoring which was true in my case. I’ve never been very big but I had began to feel it in my clothes and when walking the dog k was puffing more. I never realised how much a few extra kilos had impacted my health. If wasn’t until after I’d lost 10 kgs and our 6 year old granddaughter stays the night and said “you don’t snore anymore Grandma”. I asked my husband and he said it was true.
Extra weight can impact joints and many other issues so as a sufferer of rheumatoid arthritis and fibromyalgia I needed to do something. This and other books by Dr Moseley (and his son Dr Hack Moseley and his wife Dr Gail Bailey) have helped me get back on track after lapsing during winter here in South Australia. I knew I had gained almost half of what I’d lost over 4 months ago the so now I’m back on track to my goal weight again.
April 6, 2023
This book has a great balance of how to do the diet and why it is good for us, backed up by research. It's pitched at the right level too. Interesting and motivational.
August 26, 2024
I have to lower my cholesterol and losing weight might do that, and this is recommended as a healthy fast way to lose weight.
May 22, 2025
This book basically repeats again and again that you should go to the website where you’re encouraged to spend £99 on 12 weeks membership to do the Fast 800.
I’m not completely sold on MM gaining a relatively small amount of weight then losing it with an 800 calorie diet. I’d like to hear from someone with multiple stones to lose and who has had long-term issue with their weight. While the idea of losing weight fast appeals, the reality of doing the diet might be tricky. Only one way to see I guess.....
Also, how does this measure up long-term? Do people keep off the weight, or is it near impossible after depriving yourself of so long not to eat everything in sight? I’m wondering whether this kind of regime might result in binge eating and see-sawing issues with food. I think I’m still of the slow and steady, sensible approach while not being hungry weight, loss brigade
Nowhere does Mosley tackle actually how to live life and approach the food culture and social aspects of sharing food around us on such a restrictive diet (if you’re choosing to do it full time.)
If you want a really solid book based on research by the author, who is a medical professor at Cambridge University, then I’d recommend you read Giles Yeo’s Gene Eating.
14/05/19
I’m not completely sold on MM gaining a relatively small amount of weight then losing it with an 800 calorie diet. I’d like to hear from someone with multiple stones to lose and who has had long-term issue with their weight. While the idea of losing weight fast appeals, the reality of doing the diet might be tricky. Only one way to see I guess.....
Also, how does this measure up long-term? Do people keep off the weight, or is it near impossible after depriving yourself of so long not to eat everything in sight? I’m wondering whether this kind of regime might result in binge eating and see-sawing issues with food. I think I’m still of the slow and steady, sensible approach while not being hungry weight, loss brigade
Nowhere does Mosley tackle actually how to live life and approach the food culture and social aspects of sharing food around us on such a restrictive diet (if you’re choosing to do it full time.)
If you want a really solid book based on research by the author, who is a medical professor at Cambridge University, then I’d recommend you read Giles Yeo’s Gene Eating.
14/05/19
January 7, 2019
Practical health advice that works!
I've followed Dr Mosley's work since watching the BBC Horizon documentary on fasting. I started intermittent fasting to become comfortable with being uncomfortable and avoiding eating poor food when travelling for business.
This latest book refines his advice based on the latest Scientific research. It is focused on the ideas of intermittent fasting (reducing your calorie consumption to 800 or less each day - which is surprisingly easy) and the Mediterranean diet (lots of Olive Oil, fruit and vegetables).
The book is full of plain English explanations of the latest research, and has practical instructions on how to use this diet yourself. There are also a lot of recipes for meals which fit into the diet.
Having used intermittent fasting over the past two years, I'd recommend this book to anyone who wants to lose weight or increase their energy levels.
I've followed Dr Mosley's work since watching the BBC Horizon documentary on fasting. I started intermittent fasting to become comfortable with being uncomfortable and avoiding eating poor food when travelling for business.
This latest book refines his advice based on the latest Scientific research. It is focused on the ideas of intermittent fasting (reducing your calorie consumption to 800 or less each day - which is surprisingly easy) and the Mediterranean diet (lots of Olive Oil, fruit and vegetables).
The book is full of plain English explanations of the latest research, and has practical instructions on how to use this diet yourself. There are also a lot of recipes for meals which fit into the diet.
Having used intermittent fasting over the past two years, I'd recommend this book to anyone who wants to lose weight or increase their energy levels.
January 20, 2019
Does this even count as a book to put on GoodReads?
Have I started documenting things obsessively?
How clever of Dr Mosley to persuade me to buy a book almost identical to the one I bought about 3 years ago.
Been 5: 2ing most of the time ever since but stopped last year and my weight crept back up. Been 5:2ing again for the last couple of months and it's not made a blind bit of difference.
So...I'm going for the 800 calorie crash diet for a fortnight (I know they don't like the phrase crash diet - but that's what it is).
Have I started documenting things obsessively?
How clever of Dr Mosley to persuade me to buy a book almost identical to the one I bought about 3 years ago.
Been 5: 2ing most of the time ever since but stopped last year and my weight crept back up. Been 5:2ing again for the last couple of months and it's not made a blind bit of difference.
So...I'm going for the 800 calorie crash diet for a fortnight (I know they don't like the phrase crash diet - but that's what it is).
February 11, 2019
This isn’t rocket science and there’s lots in here that I already know. However sometimes it’s good to take stock, read and get the diet back on track. I’m not up for the 800 calories for 2 weeks plus but 5:2 is certainly doable. Lots of science to back up the claims which is useful. And most importantly some lovely recipes to try out. Meal planning and good food to try. Got to be worth a go!
December 16, 2019
A refreshingly practical and hype-free book about diet and disease prevention.
I like that Mosley shows the rationale and the scientific research behind different kinds of restricted eating patterns that can achieve the same results. Clearly written and informative. The second half, with exercise advice, recipes, meditation info etc seemed more like filler.
I like that Mosley shows the rationale and the scientific research behind different kinds of restricted eating patterns that can achieve the same results. Clearly written and informative. The second half, with exercise advice, recipes, meditation info etc seemed more like filler.
July 8, 2021
Life-changing.
I was interested so I read it. The ‘science’ appears to be backed up with evidence and the results I’ve seen in others are astounding. Really easy to read without patronising or lecturing.
Do it or don’t do it; it makes no difference to Mosley. He just gives you an option; Underneath a massive neon sign.
I was interested so I read it. The ‘science’ appears to be backed up with evidence and the results I’ve seen in others are astounding. Really easy to read without patronising or lecturing.
Do it or don’t do it; it makes no difference to Mosley. He just gives you an option; Underneath a massive neon sign.
February 18, 2021
Feels like I read a bad infomercial. Yes, you can lose weight if you cut calories. Especially, if it's 800 calories. I was hoping for some science to back up some of the information. A lot of the information is debatable.
Read
June 30, 2019Dr. Mosley combines the latest science and thinking on diet and weight loss into a comprehensive lifestyle program that provides both immediate and long-term results. This book includes the how and the why for 2 to 12 weeks of an 800-calorie, low-carb, Mediterranean style diet, which is then followed by Dr. Mosley's own 5:2 diet for as long as it takes. He has also discovered that results may be realized even more quickly by concurrently using a Time-Restricted Eating technique during both diet phases. It's a lot of information in one small package, but the author makes it all seem sensible, doable, and urgent.
July 15, 2019
A highly informative book on improving one's health: how to lose weight, reverse diseases, boost brain health, and more. The author presents a three-phase program designed to help you achieve these results. The book also includes meal plans and recipes for the reader to try. A must have for anyone looking to improve their overall health.
Thank you to Michael Mosley, NetGalley, and Atria Books for an ARC of this book in exchange for an honest review.
Thank you to Michael Mosley, NetGalley, and Atria Books for an ARC of this book in exchange for an honest review.
September 23, 2020
I read this book in 2 days. It was very matter of fact, and had good information for an absolute beginner. It was definitely helpful, but I found the content rather redundant. Overall worth the read if you're interested in beginning intermittent fasting with fast 800. There's also a companion cookbook.
March 23, 2019
Time to give this a try
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