Why have I gained/maintained weight doing The Fast Diet/5:2 diet?

During the first month of 5:2 intermittent fasting your body will go through a period of adjustment. Water weight is lost in the early stages, followed by fat loss – but some water is also regained.

For this reason many new Fast Dieters find that their weight can yo-yo somewhat during the first month of this way of eating. They lose a lot of water weight, then find the scales stay the same for a week or two as fat is lost but water is regained. Sometimes they’ll find the scales go up a little before going back down. This is perfectly normal. Although most fasters find that they will have a significant loss in the first week, others who were not retaining so much water will find that the loss comes along in week 2-3, with no initial loss at all.

The key to it is perseverance and gaining a better understanding of how your body weight fluctuates naturally.

If you were to weigh yourself every day (even if it is at the same time of day) you would find that the numbers can vary by several lbs (or even more, depending on your size). This is for all sorts of reasons, including what you’ve had to eat recently (some foods cause increased water retention), whether there is still food in your gut, hormones at different times of the month and any number of other mysterious reasons.

Bearing this natural weight variation in mind then it is easy to see how one might be deceived by the scales as a weigh in might indicate no loss or even a small gain – but this could very well be down to your natural weight changes. It is often only over the longer term that we can see the bigger picture and really notice the downward trend of the numbers on the scales. The moral of the story? Don’t put all your trust in the scales – try a measuring tape too as this will tend to be more honest with you! At the end of the day, what’s really more important? The number on the scales or the shape and size of your body?

If you are quite active or are exercising in addition to fasting then you also need to remember that muscle weighs more than fat, so even though you’re losing fat if you are gaining muscle too then your weight may very well go up – but your body shape will be changing for the better!

Unfortunately the above is not the only explanation for weight gain or maintain on the 5:2 diet…

There is the possibility that you are overeating on your feed days and therefore negating the calorie deficit from your fasting days. Many users at the forum report having gone through a phase of overeating in the early stages of intermittent fasting, but happily find that within a couple of weeks the novelty of no foods being forbidden soon wears off and normal eating resumes. It may not even be something as obvious as overeating – beware the calories that sneak in through drinks such as fancy coffees, fruit juices and smoothies! A single piece of cake or muffin can contain as many as 600 calories, so choose sensibly or have it instead of your breakfast or lunch (obviously don’t do this every day, that wouldn’t be healthy – but surely better to eat the cake instead of lunch rather than in addition to it?) If you think you may be eating too much on your feed days please see the post about TDEE for more information. Something interesting I picked up from The Men Who Made Us Fat is that most people don’t try to balance their eating – so for example if they have eaten an entire ‘sharing bag’ of crisps to themselves one would expect them to cut back on the following meal as they have already had plenty of calories. This is sadly not the case and most people will eat extra without trying to balance it out over the course of the week. There is no harm in skipping or reducing the size of an occasional breakfast or lunch to balance out your intake. Indeed, there is some debate as to whether breakfast as important as it has been made out to be over the years. I for one do not feel hungry on waking up but for many years have eaten breakfast because it’s what we’re told to do. These days I try not to eat unless I’m hungry (or if I really, really, really want something – not just fancy it) as I’ve learned to listen to my body more. If I don’t wake up hungry I don’t eat until I feel hungry – often this is midmorning or nearer lunchtime, by which point I find I don’t need such a large lunch later on as I’m still full from breakfast.

But I digress!

Another possibility, believe it or not, is that your are under-eating on your feed days. It may seem contrary but in some cases if you are calorie restricting on your feed days as well as fasting it can be detrimental to your metabolism. Although there is debate as to whether ‘starvation mode’ really exists, it does seem that if you don’t eat enough your body will try its best not to lose weight. In all fairness under-eating is not often the cause and if you are in any doubt about your intake please do check your TDEE and consider keeping a food diary at least in the short term to assess your intake vs your body’s calorific needs.

The final possibility (well, there may be others but this is the final one I’m listing) is that you have an undiagnosed medical condition such as a problem with your thyroid, metabolism or diabetes. If you are concerned that you are not losing weight (please do give it at least a month of no loss first) with this method and are not under or overeating then do consult your doctor.

There’s a really informative topic over at the forum which you might find useful too:

Why do the scales show an increase when I’ve been so good?

Can anybody do The Fast Diet/5:2 diet?

Fasting is not recommended for the following types of people:

  • Type 1 Diabetics
  • Pregnant or breastfeeding women
  • Women trying to get pregnant
  • Anyone who has or had an eating disorder
  • Under 18’s
  • Anyone who is currently underweight (BMI of under 18.5)

If you have any doubt as to the 5:2 diet’s suitability for you please consult your medical practitioner before beginning.

Can I really eat whatever I want?

Yes, but possibly not in the way you think.

This is a common misconception about the 5:2 diet. It is not an excuse to enter a cycle of binging and starving, which is of course not healthy or advisable.

You can eat whatever you want on your feed days in the sense that no foods are forbidden. This doesn’t mean that you can eat as much as you want. If you over eat you will of course undo the calorie reduction obtained through your fasting days.

While the books, TV documentary etc tell you to eat ‘as normal’ on your feed days, it’s clear that many of us who have (or have had) weight problems do not really know what ‘normal’ is when it comes to eating. That’s probably what gave many of us these weight problems in the first place! Those of us who are out of touch with what a normal food intake is may need to count calories or at least be a bit more aware of what we are eating on our feed days. But the issue of daily calorie requirements is another topic altogether, you can read more about it here.



Does the 5:2 Diet/The Fast Diet really work?

Yes, it does! I’ve been doing it for almost a year now, have lost over 3 stone and I still love this way of eating.

Don’t just take my word for it though. We’ve a whole community of thousands 5:2ers/Fast Dieters at The 5:2 Fast Diet Forum the vast majority of whom have had great success with this way of eating – even those with type 2 diabetes or thyroid problems.

Above all else (although there are other factors of course), weight loss is about calories in versus calories out. By drastically cutting back on your calorie intake two days a week you will create a calorie deficit over the week, resulting in weight loss.

The 5:2 diet isn’t a quick fix, after the initial higher losses (which one experiences with almost any diet) the loss tends to slow to a more manageable 1lb per week. This may not sound like much but bear in mind that you’re not having to cut out entire food groups from your diet nor are you denying yourself each and every day of the week. It’s sustainable, and that’s where other diets often fall down.

Most of us following the 5:2 plan don’t like to think of it as a diet. It’s not a diet, it’s a sustainable way of eating for life.

The figures speak for themselves. We’ve been gathering weight loss data from thousands of Fast Dieters at the forum and compiling the data into charts, figures and statistics demonstrating the fantastic 5:2 diet results achieved across a broad range of people around the world.

On the rare occasions that users complain the diet isn’t working it tends to be either a case of vast overeating on their feed days (thus negating any calorie deficit from the fasting days), miscalculation of calorie intake (try keeping a food diary to work out what you’re actually consuming) or an undiagnosed medical condition such as a problem with the thyroid or metabolism.

The vast majority seem happy to stick with this way of eating and report that they have had greater success with this method than with other plans or slimming clubs. What’s especially appealing is that this method is totally free! There are no membership fees to pay, no fancy foods to buy – you don’t even need to buy the book. All the info you need is available online. It’s a simple, effective method for weight loss.

Where did the 5:2 diet/The Fast Diet come from?

The 5:2 Diet also known as The Fast Diet is a form of intermittent fasting.

Intermittent fasting has been around for a long time, predominantly in the form of ‘ADF’ – Alternate Day Fasting, where ADFers fast every other day.

This particular variation of intermittent fasting was made popular and brought to the attention of the media by Dr Michael Mosley with his BBC Horizon documentary, Eat, Fast and Live Longer. The documentary aired in early August of 2012 and sparked various books including Kate Harrison’s 5:2 Diet Book and Dr Mosley’s own The Fast Diet book (co-authored with Mimi Spencer) along with a plethora of others and subsequent recipe books.

The original Horizon documentary, “Eat, Fast and Live Longer” can be seen here. For me, this was a life changer as I took to the diet immediately after watching it!

There’s also a really handy little video on YouTube “The Fast Guide to The Fast Diet” for those who don’t have or can’t be bothered to read the book.

Will I feel hungry, weak, tired, cold, dizzy and get headaches from fasting?

Simply put: yes, maybe, maybe, maybe and maybe!

But, that’s just in the early days – your body needs time to adjust to fasting and you may well experience things which you are not accustomed to – we’re all so used to just having something to eat when we feel hungry, most of us have forgotten what true hunger feels like. Many are afraid of it, but there’s nothing to be scared about.

The vast majority of ‘fasting side effects’ will pass within a few fasts. Just stay determined and you’ll be fine!

If you feel hungry when fasting, it will pass. Hunger does not get progressively worse and worse – it will usually pass within a few minutes and can often be helped on its way by a nice glass of water.

If you feel weak or dizzy when fasting, it’s probably just your body complaining about a lack of food (in particular, sugar) when it’s been used to regular feeding. In the early days of fasting you may want to split your calories up throughout the day and allow yourself something to eat or drink if you feel weak.

If you feel tired when fasting, more often than not this is a sign of dehydration. Most of us don’t drink enough clear fluids in general, and this becomes more obvious on a fasting day. Make sure you drink plenty of water or low calorie liquids to keep yourself hydrated. It’s amazing what a difference a glass of water can make!

If you feel cold when fasting, this is quite normal especially for women (and all the worse during our menstrual cycles!). A salty drink will help to warm you up, perhaps a low calorie soup or better yet a stock cube/bouillon or marmite drink for a really low calorie alternative to do the trick.

If you get headaches when fasting, this can also be a sign of dehydration and can be remedied with a nice glass of water. You can take paracetamol if the headache persists (don’t have aspirin on an empty stomach) as well. Another possibility is that the headache is a withdrawal symptom from something you would usually consume such as caffeine. In this case, don’t cut the caffeine out of your fasting days, but find a way to enjoy it in a low calorie version, i.e. black coffee or black tea. If you’re going to add milk or sugar (maybe Stevia, although expensive it is calorie free) make sure you account for these as part of your calorie budget for your fasting day.

Before long you’ll be used to the feeling of hunger and won’t even notice it. Most days will be quite easy, although as with all things in life there will be exceptions – I still have an occasional fast which I find challenging. Once in a while I still get a headache and I certainly feel the cold more on my fasting days.

How does the 5:2 Diet work?

Essentially the 5:2 diet/The Fast Diet works by reducing your calorie intake across the week.

One pound (1lb) of fat is the equivalent of approximately 3,500 calories, therefore to lose 1lb of fat per week one must reduce one’s calorie intake by that amount or burn off that amount of calories through exercise.

Many of us who have been overweight love our food and struggle to cut back our calorie intake on a daily basis – we may achieve it in the short term through fad diets, slimming clubs etc however in the long term those of us who love our food tend to struggle to stick to these restrictive ways of eating and will fall off the diet wagon before too long. Once we go back to our old eating habits, the weight piles back on – often with re-enforcements and the yo-yo dieting begins anew!

With the 5:2 method we need only worry about cutting back our intake on two days a week. Yes, it’s a drastic cutback but this allows us to eat as normal on the other five days. It’s a part time diet, making it really easy to stick to and therefore more of a long term way of eating than a diet. In addition to helping us to lose weight the 5:2 diet seems to change our eating habits for the better. For one thing we find our appetites decrease, particularly the day after a fast when our tummies have shrunk and do not wish to be overloaded with food. We learn to listen to our bodies needs rather than just what we want and we start to make smarter food choices based on the knowledge we have gleaned from our fasting days and being so careful with a calorie budget!

What is the 5:2 Diet/The Fast Diet?

5:2 Fasting is a simple way to reduce your calorie intake over the week without making yourself feel deprived and as if you are constantly on a ‘diet’. So many people diet only to get fed up of the constant restrictions and feeling guilty over ‘treats’ – this makes many diets difficult to stick to in the long term and more often than not any weight lost will be regained, often with extra weight. Yes, some people do manage to stick to these other eating plans and keep the weight off – but most of us do not want to go without our favourite foods forever.

With 5:2, you simply have 2 non-consecutive days a week where you eat only up to a quarter of your recommended daily intake of calories. For men this is usually around 600 calories and for women around 500 calories. It’s simple – go to bed on a feed day, wake up and consume no more than 500/600 calories for your fast day, go to bed, wake up and eat as normal. So, you’re only ‘dieting’ 2 days a week – some people call these days ‘repair days’ or ‘very low calorie days’ instead of ‘fast days’, as it is not technically fasting. You can split your calories however you like on your fasts, whether you want 1 large meal, 2 medium sized meals or 3 smaller meals. The other 5 days are often called feed days or feast days – but be careful not to take the term ‘feast’ literally, it is only meant in terms of the lifestyle mimicking a natural state of ‘feast and famine’!

It’s simple, and easier than you might think. The idea of fasting can sound daunting, but once you learn that hunger is only a fleeting feeling and can soon be quelled with a drink of water, black tea or coffee, it just gets easier and easier. You’ll probably also find your tastes in food change somewhat, when you realise how good your lovely filling veg and protein taste on your fasts and how good it makes you feel!

Read full article: “What is the 5:2 Diet?”

A new 5:2 Diet blog :)

Well, I’ve been doing the 5:2 diet for some 10 months now, and running a successful 5:2 Fasting Forum for almost half that time. It’s been a bit awkward setting up extra info pages on the forum site and so I thought I’d start a separate 5:2 site/blog for ease of updating & adding new pages – think of it as a sister site to the forum.

I’m not sure if I’ll be blogging here as such or just posting up interesting articles and static pages. We’ll see how this develops over time I guess!

Still a bit of tidying to do here, like replacing the default images and updating the footer text. I should try to sort out some kind of logo in the same vein as the 5:2 forum header too. All in good time! I doubt anyone’s even reading this as yet, being unfinished and not yet submitted to good old Google.