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« The Simplest and Most Effective Method of All? | Main | The One Must-Do Task Each Day »

And now for something completely different...

Three times in my life I’ve managed to lose a significant amount of weight through dieting - each time it’s been a different diet but the rate of loss with all three has been about 1 lb a week.

Unfortunately once I’ve lost the weight I’ve always been faced with the same two problems:

  1. I haven’t been able to stop myself putting the weight on again.
  2. I haven’t been able to keep to the same diet a second time.

I’ve been reading quite a lot recently about the benefits of fasting, which are far from just confined to weight loss apparently. I won’t go into what they are as, if you are interested, you can easily research them on the internet.

I decided to embark on a fairly intensive diet in which I ate normally on alternate days followed by a day in which I ate no more than 600 calories.

This worked very well to start off with. I didn’t find it difficult to keep to and I lost about 6 lbs fairly quickly. Then I found that I was no longer losing weight. I seemed to put on as much weight on the non-fasting days as I lost on the fasting days. This wasn’t due to bingeing on the non-fast days. I wasn’t tempted to binge in the slightest.

So I decided to up the stakes and go for a full 24 hours on and 24 hours off alternate day fast. This is supposed to be very beneficial but is also supposed to be very difficult to keep to. But it struck me that there was a very simple way of making this much easier. All one had to do was to make the change-over between the days at 12 noon instead of 12 midnight. This would mean that I would be getting the benefits of a full 24-hours without food, but still getting at least one meal every day.

So the days look like this:

Day 1 Breakfast

Day 2 Lunch and Supper

Day 3 Breakfast

Day 4 Lunch and Supper

Day 5 Breakfast

and so on.

The result of doing this has been fantastic. I’ve continued to lose weight (at about 2 lbs per week). I’ve only felt pleasantly hungry - otherwise I’ve felt great, with a lot more energy. I’ve not been tempted to binge, and I actually prefer being on the diet to not being on it.

One problem with diets like this is social events. I don’t live in isolation. There are plenty of occasions when I want to celebrate or I’ve been invited out, or there’s a celebration on a special day. How do I handle these?

  1. I never deviate from the basic 24-on/24-off rhythm. That means that I know in advance which days are going to be “on” and which “off”. So as far as possible I plan my social calendar so that eating out takes place on “off diet” days. However that’s not going to work for everthing, so:
  2. I have perfected the art of sitting at a dining table and watching other people eat. I think about it in the same light as watching a cooking programme on TV. In other words I think of it as an enjoyable experience, and not as a battle against temptation. And it really works! This is OK for family members and others who are used to my strange ways, but like 1. above is not going to work for every situation - so:
  3. If all else fails, the diet is sufficiently robust to survive occasionally adding an extra meal in. You would still ony be eating 2 meals that day. But it’s really important to make these exceptions as rare as possible.

I’ll report on further progress (or lack of it!) in due course. I’m hoping that this is going to be something that solves the two problems I had with my three earlier diets.

Reader Comments (29)


Yes for me loosing weight has always been fairly straight forward, keeping it off is the difficult bit.

Since 1 January this year I've lost 4 and a half stones (63lb) and currently tip the scales at a very reasonable 12st 6lb (I'm a 5ft 11inch tall male, 44 years old). Buying 32inch trousers for the first time in 5 years.

Before and after pictures are in my blog post here:

I think I might consider an alternate fasting method to keep the weight off - I'll be looking for updates from you on this one - and good luck!
October 15, 2012 at 17:55 | Unregistered Commenterjohnwin
Congratulations on the diet results! I also did some research on fasting recently and have attempted to fast at least 2 days/wk, but usually at least 1. I like the idea of the alternate day fasts.

I thought I'd be writhing in agony my first day but, as you say, if you adopt a schedule whereby you eat everyday and still get in a 24-hr fast, it's remarkably effective and easy.

What's fascinating is noticing how my body responds to hunger and the stories I tell myself (or that the gremlin voices tell me) about the hunger. I notice that the hunger comes in waves and even if I feel really hungry now, the feeling will pass.

I can easily distract myself from hunger with an involving activity, and I drink plenty of beverages (tea, seltzer water, etc) to keep me full.

And it's become easier to tell the difference between hunger and a craving. I have found that many of my hunger cues are instead boredom, or the need for socializing, or a timed habit (the guys in the office always go out to lunch at the same time every day). So evaluating what is real hunger from what is not has been a real side-benefit.

One thing I read said that we make about 250 decisions a day regarding food (I have no idea where I read that, so take with a shaker of salt). By fasting I take all those decisions off the table, as it were. It frees my mind to an incredible degree. I don't have to plan meals to take to work or what to order in a restaurant or what snacks are allowable. During a fast, every food choice is a yes/no decision and it takes little cognitive energy to decide "no." Besides, once I've passed the 18-hr mark, getting to 24 is a matter of pride :)
October 16, 2012 at 4:35 | Unregistered CommenterMike Brown

Fantastic achievement. Four and a half stone is a lot. You are the same height as me, and I will be very happy to get down to 12 stone 6.
October 16, 2012 at 9:34 | Registered CommenterMark Forster

Thanks for your interesting thoughts and experiences. I've not found hunger to be a problem - though being retired I don't have work colleagues to contend with!

During the fasting 24-hours I feel a certain amount of hunger around 7 or 8 in the evening (which is the time we normally eat) but it's not severe and usually dies away as the evening goes on. I've never felt any hunger at all the next morning.

One thing I've become aware of is how torpid a full meal makes me feel compared to the lightness and energy that comes from the fast.
October 16, 2012 at 9:41 | Registered CommenterMark Forster
October 21, 2012 at 2:23 | Unregistered CommenterJJ

Thanks, interesting article.
October 23, 2012 at 12:31 | Registered CommenterMark Forster
I've been trying this for a week now, and the results are impressive: consistent weight loss, increased energy levels, and relatively easy to stick to.

One question: I'm experiencing increased energy levels only on eating days. The days I'm fasting I'm definitely less energetic, about the same as I felt before starting this diet. Is this your experience also? I'm trying to find a way to carry that increased energy into my fasting days as well, any hints on how to accomplish that are appreciated!
October 23, 2012 at 15:55 | Registered CommenterNicole
I expect it's a biological fact Nicole, although over time you will adapt slightly. If this works well, maybe your high and low energy points will be higher than now. I'm only guessing.

I'm wondering about exercise. When is it good, when not? Normally, the advice is to eat protein after, and don't exercise on a full stomach. But it hardly seems a likely time to exercise after a day of fasting, neither before nor after you resume feasting. Nor at the beginning of the fast. Is there any guidance?
October 24, 2012 at 2:32 | Registered CommenterAlan Baljeu
I've experimented with intermittent fasting too after reading the e-book Eat Stop Eat which seems to get a number of mentions online. Then there was an interesting Horizon documentary recently exploring the benefits of calorie restriction and fasting. I recommend it.

I've read that 18-24 hours is the magic period to allow benefits to occur, though I would have to check references to back that assertion up. In order to fit that in socially I do something similar to Mark, though I go from dinner in the evening through to dinner the next day, skipping breakfast and lunch and fasting for approximately 24 hours, depending on dinner time. It doesn't really feel like deprivation, but then I work in an office 5 days a week and don't have to contend with social lunches most of the time.

October 24, 2012 at 15:47 | Unregistered CommenterMatt Gregory
Mark, congratulations to your success in losing weight. I only wonder whether your diet is only about to eat or not to eat. Do you eat all kinds of food and beverages during the "eating-on" periodes?
I started a diet about 5 weeks ago, it is called Metabolic Balance ( When I learned about it, I was rather sceptical, it was actually my long-time doctor who convinced me to give it a try. It is based on an analysis of your blood which is used to give you a list of food you are supposed to eat (e.g. for meat I'm allowed to eat beef, lamb and venison). In the early phases you have strict rules how much and what kind of each category (protein, veggies, fruits) you are allowed to eat (but on the other hand you shouldn't skip meals) - and only water to drink (exception: a cup of coffee or tea with your meal). There are some other rules like leaving at least 5 hours between meals and always start with some protein.
Later on the rules are less strict, esp. in the last, the life-long phase, where you have two days complete "freedom". The aim is to change your metabolism.

So far I'm very happy with it - I lost 8 kg and feel much better. I very rarely feel hungry and I'm much more active. And it is much easier than expected, since I have 3 full meals per day - and I'm even able to walk past the bowl with chocolate in the office :-)

1) It is a bit of work to prepare meals (I used my kitchen scale more during the last 5 weeks that the 10 years before)
2) It is not cheap
October 25, 2012 at 22:32 | Unregistered CommenterChristian G.
Christian G.:

No, this diet is not about what to eat, only about when to eat. The advice is to eat "whatever you like" on the eating days. I've read that there is some research which suggests that there is no difference in weight loss between those who eat whatever they like and those who eat a restricted diet on eating days. The other benefits - reduced blood pressure, reduced cholesterol levels, etc - remain much the same too. I'll try and find the reference.

October 26, 2012 at 22:05 | Registered CommenterMark Forster
Reading this blog I was directed towards the Beeminder site.
The simplicity of having a visual road to make sure you
are attaining your goal (staying on pace) has motivated me.

Plan: eat 1500-2000 calories per day
exercise 1000 total calories per day
Result: lost 5lbs first week lost weight every day for 7 dats straight
October 28, 2012 at 9:56 | Unregistered CommenterAndy Rumple
Thanks so much for this, Mark (and others who've commented).

I'd also read a lot about intermittent fasting ( I also read Brad Pilon's "Eat, Stop, Eat"), and have struggled for years to find a way to be healthier and to lose weight--which over the years (I'm 62) went from 155-160 pounds in college to well over 200, as high as 255, but for the past several years around 240. If I was successful in the past, it was rarely for more than 3 months or so. Then I'd "fall of the wagon" and go back to old eating/exercise habits and gradually re-gain.

I got more serious about it this summer (no particular reason--as I said, I've tried before--perhaps it was just time?) and began a program of walking and eating lower carb and much less wheat/grains, in particular. From the beginning in mid-August I started around 235 and moved down to 217 by fairly early in October, when I plateaued (partly because of relaxing a bit on diet content). I was also experimenting with Martin Berkhan's "Leangains" approach to diet (not his exercise . . . not yet anyway), which calls for regular 16 hour fasts--i.e. your eating falls within an 8 hour window, fasting the rest of the time--e.g. eat between noon and 8 PM, fast until the next noon--his personal norm is eating between 2 and 8 PM--he also cycles macronutrients with his exercise to maintain an extraordinarily low bodyfat percentage and big musculature--see his website for pics).

Mark's post, however, inspired me to try a more regular 24 hour fast, which I started this week--the final tally will be tomorrow morning, but my weight has thus far (on Sunday--Monday AM is weigh-in time for the record) gone from 217 to 213 . . . after being around 217 since Oct. 8.

So, to say I'm pleased would be understating it!

I haven't found it difficult, but since I'm still working, I won't do every-other-day but set two fasting days/week. My schedule will look like this, most of the time (adjustments as necessary, depending on social calendar):
M - B, L, D
Tu - B (then 24 hour fast until breakfast Wed)
Wed - B, L, D
Thurs - B, L, D
Fri - B, L, D
Sat. B (then 24 hour fast until breakfast . . . or lunch Sun)
Sun. probably just lunch dinner

Other changes:
A very interesting article in The Atlantic: as well as:

and an associated blog by someone who read the article:

This led me to buy a fitbit ( and download their free app for my iPhone, plus another free app called MyFitnessPal. The fitbit device tracks steps/mileage walked each day and has helped me make conscious choices about walking more (I try to do so during the day, park farther from my office, etc. in addition to my walk of about 30' each morning). MyFitnessPal can link to fitbit's website (and vice versa), but is used for tracking what I eat, macronutrient values, etc. (in reading reviews, they have a larger database of foods). Easy to use (don't know if there's a UK equivalent), it includes many popular restaurant chains and their menus already built in.

All of this has been helpful to keep me more conscious of what I eat and what I do. It takes very little time to track eating and the fitbit just goes on my belt in the morning and stays there.

Finally, I also bought a recumbent (easier on my back) Exercycle this summer, used occasionally at first, slowly built up physical capability and am now doing the Sprint 8 protocol. You can read about it in a book by Phil Campbell, "Ready, Set, Go," but can find info on it on the web:

Mercola has another post online which speaks to his results and benefits:

The big thing about this protocol is much higher growth hormone release. As Mercola states, the benefits of growth hormone release (which naturally drop off as we age) are several, but all are anti-aging:

Decrease in body fat
Improved muscle tone
Firmer skin and reduces wrinkles
Increase in energy and sexual desire
Improved athletic speed and performance
Ability to achieve your fitness goals much faster

The protocol can be summarized as 20 minutes exercise divided as follows: 2 minutes easy, then 30 second "sprint," then 1:30 recovery, another 30 second sprint, etc. done 8 times, which gives you 20 minutes. The sprints (which can be done on lots of equipment or with running sprints--I find the recumbent bike easier on my back and easier to control the difficulty level, since as I get fitter I can just increase how hard it is to pedal) are supposed to build in intensity, with the last 3-4 being very intense--I think Campbell described it as, "after 15 seconds you should feel like you can't go on at that level, but then just hang on for the last 15 seconds."

I'm only now to the point where I'm able to work that hard the last few sprints in the sequence (a period of cluster headaches interrupted my progress). I only do it twice a week and also follow Campbell's instructions about nutrition around the Sprint 8 (a little carb beforehand + two grams of glutamine; then no sugars for two hours afterward, but at least 25 grams of protein--which I take in a protein shake. That means that I have a relatively low calorie (and very low carb) dinner on the two days I do Sprint 8 as well.

I do have to say that even when I was on a plateau around 217 pounds, I was probably adding muscle and losing fat, since my pants continued to get looser. I was wearing extra large shirts and now they're all too big, so I've switched to large. My 42 inch waist pants were tight, now the 40s are getting loose (without a belt I can pull all of them down over my hips without unfastening), and my one old pair of 38s fit almost perfectly. I'll probably hang on with the 40's until 36 inch pants will fit before buying some new ones.

I have a long way to go to get where I'd like to be, but feel that I'm finally moving in the right direction.

Mark's post reminded me to try a 24 hour fast twice a week and so far it's been easy and effective. I'll let you know if the results keep up (I don't expect 4 pounds a week as this initial week, but will be very happy with between 1-2 pounds/week).

Many thanks, Mark and good luck to all of you in your health goals!

October 29, 2012 at 0:10 | Unregistered CommenterRichard Sparks
So, more than a month later, how is this alternate-day fasting working for people?
December 5, 2012 at 18:20 | Registered CommenterDeven
I've only been doing 5:2 for a couple of weeks and I'm quite pleased with the 2 kg I've lost so far.

And looking at Mark's progress at , he should be pretty satisfied with the more than 15 lbs he has lost during the autumn!
December 7, 2012 at 14:26 | Unregistered CommenterKjell S
I, too, have been interested in intermittent fasting (IF), for a while. I have read "Eat Stop Eat," as well as "The Alternate-Day Diet." Also, I'm reading a new book that has just been published titled "The 8 Hour Diet." There is a free ebook on intermittent fasting available at, if you register.

Here's a run down on the different books. The author of "Eat Stop Eat" suggests fasting 24 hours a couple of times a week. The author presents studies that back up intermittent fasting.

"The Alternate Day Diet" proposes eating 500-600 calories every other day, while eating normally the other days. The author also references studies to back up his theory

"The 8 Hour Diet" proposes eating all your meals within an 8 hour window at least 3 days a week. This new book has lots of references to recent studies done showing that intermittent fasting is beneficial for prolonging your lifespan, as well as losing weight. There are other benefits mentioned as well.

The fast5 ebook suggests limiting eating to a 5 hour window daily, from 5PM-10PM. There is a forum on the website, as well as a Yahoo group.

Mark, are you still following the plan in your article? Are you losing weight consistently?

Sally M
January 2, 2013 at 5:14 | Unregistered CommenterSally M
Mark -- how are you doing on the fasting plan? I wobbled through the holidays, and recently got my scheduling back on track such that I can do a full 24-hour fast once a week.

I also find it much easier these days to skip lunch with my co-workers or go out with them and only have water or tea while they eat.
February 7, 2013 at 19:08 | Unregistered CommenterMike Brown
This reminds me of James Webb Young's system for productivity from the 1930s.

It goes like this :

- Make a list of everything that is really important to be done
- Pick the most important of the bunch
- Do the one on the top, and ignore the rest
- Repeat daily
February 23, 2013 at 19:12 | Unregistered CommenterReaSon
I like Dr. Joel Fuhrman's Eat for Health approach to eating/health which automatically brings one to an ideal weight and keeps it there, feeling great in the process--a llife change where tastes and appetites change. My motivation was to get my blood pressure to normal and hopefully prevent diseases and physical/mental debilitations in my retirement as much as possible. Very simple and time efficient for me as I'll cook or make things (soups, stews, salad dressings, juicing, main dishes, bean burgers, etc) in large quantities and freeze in portions for later use. It took a lot of time intially to figure out how to make it work, reading his books, joining his website for a time to gather info and find recipes, needing a core of good tasting recipes to draw from including healthy desserts. After that, it was/is just a matter of searching for new recipes here and there. I eat whatever my host offers when invited to someone's home, and order carefully in restaurants. It's the only approach that has worked for me long term.
March 9, 2013 at 13:13 | Unregistered CommenterSue
There is one method which I follow for about 25 years now. It is called "Vollwertkost" in German ("wholefood" in English - very interesting, check the rudimentary explanation on wikipedia in English and the detailed text in German).

Very roughly:

1. Basic principle: eat food as natural (unprocessed, unrefined) as possible, but do not overdo this.

2. Eat as little refined sugar as possible [must be followed very strictly, only rare exceptions, please]
There are many disquises of refined sugar used in processed food you can buy in supermarkets and even organic food shops!) as possible => as "sweet" is addictive, this might be difficult, but keeping the dangers of sugar (caries, diabetes, induction of appetite and many more). Replace by honey/agave sirup or raisins (all in moderation) or sweet fruit.

3. Eat as little refined flour ("white flour") as possible. Replace by whole grain flour. [must be followed strictly, only few exceptions, please]

Some examples of what I eat and drink:
- whole grain pulp (with banana, apple, nuts, seeds, orange etc.)
- whole grain bread (instead of refined flour bread)
- marmelade sweetened only with agave sirup
- whole grain pasta
- raw and cooked fresh (!) vegetables (nearly every one can be roasted gently and used in a tomato sauce)
- organic meat (rarely)
- cheese, milk, eggs
- water (no sweetened softdrinks, maybe apple spritzer)
- coffee (without sugar!) (but I try to stop drinking it)
- wine, beer (rarely)
- muesli (with raisins, kind of a sweet reward)
- sweets (dark chocolate), ice cream, cake => all rarely, with whole grain flour and without refined sugar where possible.

No bookkeeping whatsoever.
April 9, 2013 at 12:57 | Unregistered CommenterChris
Mark – any update? Are you still doing this?

I had some success with Fuhrman's _Eat to Live_ program, but found that I like to eat non-nutritarian foods (not to mention drinks such as beer) too often, as my increasing weight and girth attest.

So, in the spirit of your midday-start-fast idea, I'm going to do two 24-hour fasts per week, starting on Tuesdays about 14:00 (after a late lunch), and on Fridays about 11:30 (after coffee & pastries at work). I am usually at home on the following days, with no morning appointments, and often get up late and skip breakfasts then anyway. With this plan, I think the challenge will be fasting through the initial afternoons and evenings.
August 26, 2013 at 22:21 | Registered Commenterubi

I lost quite a bit of weight using this, probably about 16 lbs or so. But I then put the lot back on over the Christmas period, when we had so many social engagements it was impossible to keep to the regime. After that experience I vowed not only to never go on another diet for as long as I lived but also never to even weigh myself again.
August 28, 2013 at 23:04 | Registered CommenterMark Forster
Haha. I guess, at a certain age, your vows make sense. But I've just turned 51, and should probably lose one pound for every one of those years. Blood pressure is too high also. So I need to take action for my health.

My Tue-Wed fast went better than I expected; got a bit weak during the last two hours, but it wasn't painful. Just started the Fri-Sat one.

It is amazing how good food tastes, if you haven't had any for 24 hours.
August 30, 2013 at 21:07 | Registered Commenterubi
Thank you, Mark, for posting your experiments into intermittent fasting. Your post was the first time I'd heard of this idea, and while the particular approach you (and Ubi) have taken wouldn't really work well for me, I did some more research and found the "leangains" approach of doing a 16-hour fast every day, eating only during an 8-hour "window" each day.

Since I have a relatively young family, this has worked fantastically for me. I simply don't eat breakfast with the children, and then break my fast at mid-day. I can then have dinner with the family, which is an important tradition for us.

I've been amazed at how well this has worked out. I exercise regularly, and have found it no problem at all to exercise in a "fasted" state -- in fact, I think my body prefers it as I don't risk "bonking" because my body is using its fat reserves.

In terms of weight loss, the results are excellent. Without having to worry what I eat at all (simply when I eat it), I've lost 5 kilograms in the last 5 weeks.

So thank you, Mark, for sharing your weight-loss experiments. You really are an inspiration to the rest of us...

- Erik.
August 31, 2013 at 19:50 | Unregistered CommenterKiwi Erik
Well after a long trial, I'm about to give up on this intermittent 24-hour-fasting approach. I've been doing it two days per week (Tue-Wed & Fri-Sat) a total of 58 times so far (with a couple of breaks during travel weeks). I've stopped weighing myself as my pant/belt size hasn't decreased noticeably. If anything, my girth has expanded slightly. :-(

In some ways, I feel like I've failed, but I guess it's just that this method has failed for me. It must be true that my body really does go into hibernation/starvation mode to maintain my weight; I know I feel colder during the fasting periods. I will weigh myself at the end of my 59th & last fast Saturday morning, and start a trial of the No S diet -

- on Monday.

One benefit of this (failed) fasting exercise is that I know I will be able to handle the no-snack rule!
April 24, 2014 at 19:26 | Registered Commenterubi
I gave up sugar, wheat and almost all carbohydrates and every single thing about me improved - weight, wasitline, visceral fat, abdominal fat, blood pressure, water retention, triglycerides, cholesterol markers, quality of sleep, desire to eat crap, increased anerobic threshold, endurance event energy and so on. It was really quite incredible.

For the science you can spend many hours on here - there are plenty of other sites but this is the most informative and data driven.
April 25, 2014 at 13:46 | Unregistered CommenterChris
Chris: a degree-qualified nutritionist friend of mine often says that sugar and wheat are 2 evils of food these day. Wheat is so processed it bears little relation to it's quality of years ago. She also adds cow milk as a bad thing - mainly due to the additives to feedstuffs. The more I reduce these 3 the better I am.
April 25, 2014 at 18:17 | Unregistered Commentermichael
I follow the Eat 2 Live diet, which leads to stellar results for me, similar to Chris above but as a vegan, no meat as well.
April 25, 2014 at 21:19 | Unregistered CommenterVegheadjones
michael, indeed, this is a good video explaining some of the chemistry
April 26, 2014 at 2:53 | Unregistered CommenterChris

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