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5:2 diet tips from Michael Mosley

5 2 diet 

Popularity for Michael Mosley's 5:2 Diet, also known as the Fast Diet, shows no sign of slowing down. From advice on how to tackle intermittent fasting to the diet's impact on weight loss and health, Dr Mosley answers all your questions. 

What is the 5:2 Diet? | Is the 5:2 Diet suitable for me?How many calories should I eat? | Is intermittent fasting healthy? | Dealing with hunger pangs | Tackling a weight loss plateau | Fasting days | Does the 5:2 Diet work?


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What is the 5:2 Diet?

The 5:2 Diet is an intermittent fasting diet popularised by Dr Michael Mosley. It involves eating normally for five days a week, then reducing your calorie count to 500-600 calories per day for two days. 

Unlike other diets, there is no restriction on what types of food you can and cannot eat, which can be easier to follow than strict calorie-focused diets. There is also the freedom to decide which days will be your low-calorie 'fasting' days. 

On fast days, you are advised to choose foods that are high in protein and fibre to help you feel full. 

Is the 5:2 Diet suitable for me?

When it comes to the Fast Diet, those with diabetes will need closer supervision as their blood sugar levels are harder to control.

According to Michael Mosley, this type of diet does, however, work well for vegetarians.


I am following a low calorie diet of approx 1200 calories a day and, although it was fine when I started, it seems to be getting harder rather than easier, as I had expected. The plus side is that it has really made me think about what I eat. The minus is that I am permanently ravenous. So, part of me now thinks that your diet couldn't be any worse than this - and part of me thinks that if I feel this bad on 1200 calories, how will I cope on 500, even if it is only for 24 hours?

Try it and see. A recent study done by Dr Michelle Harvie at Manchester University found that volunteers on a 5:2 Diet, when compared to those on a more typical 1200 calorie a day diet, were more likely to stick to it, lost more weight and had improved biomarkers.



How many calories should I eat on fasting days?

According to Mosley, the number of calories you consume on fasting days is, above all, a guideline. Here, he explains the logic behind the suggested number of calories and how long you should fast for.


Is it necessary to consume 500 or 600 calories per day and does it have to be on consecutive days to have the maximum effect?

The scientific studies are based on men consuming 600 calories and women 500 calories, so that seems a reasonable guideline. You can increase your calories, but you won't see as much change.


As I'm over 60 and reasonably active, is it okay to go over the 500 calorie mark to 600? I feel there ought to be some leeway for an older person.

As long as you are feeling good, I wouldn't get pre-occupied by numbers. This is all about finding something practical that works for you.


Why are the number of calories you can eat on fast days based on gender and not weight?

It is just a guide. If you want to eat 600 calories that is fine, but weight loss will be slower.


Am I correct in thinking that the researcher you interviewed about intermittent fasting said that ideally one should not eat anything on fast days? 

Eating calories on fast days is partly because it is easier to sustain, but also partly to keep up levels of nutrients and protein. Protein is not well stored and needs topping up every 24 hours.


I am a bit puzzled about the fast times. I start the fast after supper and, following your guidelines, eat around 500 calories during the following day and end the fast with supper. That means I eat my main meal on both days with snacks in between. To me, that isn't much of a fast. 

Fasting means abstaining from eating for varying lengths of time. I aim for 12-hour stretches, but others find that tougher. Research by Dr Michelle Harvie suggests that reduced calories twice a week, even when spread throughout the day, brings significant health advantages.


As the recommended intake for a woman who is not dieting is 2,000 calories, would it be wise to try to stick to this on the days you can 'eat what you like'? 

Yes, better to stick to your normal intake rather than try to stuff yourself on the days that you aren't 'fasting'.


healthy food 

Is intermittent fasting healthy?

"My blood pressure decreased quite dramatically when I started the 5:2, so much so my doctor repeated the test. I can only assume that this diet was the reason."

There are significant health benefits connected with the 5:2 Diet, from weight loss to reduced cholesterol levels.

6 health benefits of the 5:2 Diet

  1. Weight loss
  2. Reduces the risk of cancer and heart disease
  3. Improves cholesterol levels
  4. Helps to reduce asthma
  5. Helps to reduce the risk of developing type 2 diabetes
  6. May reduce the risk of developing dementia


How healthy is fasting when we are continuously told not to allow blood sugar levels to fall too low and to eat little and often? 

The idea that you should eat little and often to speed up your metabolism or prevent your blood sugar levels falling is largely a myth. There have been quite a few studies that have shown no difference in metabolic rate between those eating their daily calories split into three meals a day or six. Your body is extremely good at maintaining your blood glucose levels and there should be no problem, unless you are a diabetic. You would need to fast for over 60 hours to have a serious impact on blood sugar levels.



How to deal with hunger pangs on the 5:2 Diet

"I no longer have any desire to eat between meals or to eat sweets. I have my three meals at regular intervals, feel full more quickly and don't eat after 8pm. I had headaches when I first started, but they soon passed."

Whether it's altering your eating schedule or being more aware of the amount of protein you consume, hunger pangs might be an initial side effect, but, according to Mosley, they can be avoided.


I wake up in the night and am unable to get back to sleep because I'm so hungry. Does this suggest that going hungry probably isn't good for me? 

Try changing your pattern so you have a bigger meal in the evening - or put aside a few calories for a glass of milk, which can be filling.


Whenever I restrict my intake, I get so hungry that, by dinner time, I would eat anything. Where do you find the willpower?

I find the main thing is to have a protein-rich breakfast (protein is satiating), lots of fluid during the day and lots of vegetables in the evening with, say, a slice of meat or fish. What you want is bulk and protein; those are the things that keep you full. If you find you can't do 500 calories, try 600.


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How to tackle a weight loss plateau

Inevitably, during a diet, there will come a time when weight loss slows down. Michael Mosley explains why this might be and what you can do to change this.


Will my all-knowing metabolism eventually twig what I am up to and slow to a standstill on fast days?

As we lose weight, our metabolism slows simply because we are carrying less weight around. So you will find that weight loss slows down as you progress, but hopefully not until you reach your desired weight.


For the last month I have reached a standstill, although I still have some weight to lose. Do you know of any change in regime which could kick start the loss again? This diet has been so easy to follow and I am happy to continue for as long as it takes.

Look at the fluids you are drinking on your 'feast' days. Fruit juice, smoothies, lattes and booze are all calorie-rich and are not satiating.


I have been doing this eating plan for a week and found the fasting days somewhat difficult. However, I was fasting for a day and a night. I have read that you can fast for 24 hours, for example from 2pm one day to 2pm the next, which would seem far more manageable...?

Try experimenting and see what works for you. We are all different.


 The Fast Diet

5:2 diet - consecutive days or not?

"For me this has been the non-diet diet. Although I have two preferred days each week when I do it, I will switch the days around when it is necessary. You do, however, need to eat sensibly the rest of the week."

The golden rule is finding a schedule that works for you, which might mean cutting your calorie intake to the recommended fasting amount on consecutive days, or spacing these days out.


Is there a 'best way' to space out the two fast days for maximum effect? 

No, there is no 'best way'. Whatever suits you. I do it Mondays and Thursdays, but you can choose which days you want to fast - it doesn't matter if it's consecutive or not. You should lose around 1lb of fat a week; the apparent weight loss will be more because you will also lose water. Make sure you drink a lot of water on fasting days.


Is it really true that people don't binge on the days when you can eat what they like? I am sure I would be stuffing myself after the abstinence. And then I start wondering how you can possibly lose weight if you are eating - say - a Mars a day 5 days a week.

Dr Krista Varady, who has run a number of trials, found that people thought they would binge, but in reality didn't. I certainly find I eat no more than normal on 'feast' days.


5 2 Diet 

Does the 5:2 Diet really work?

"I have battled for years to lose weight and this is the first time I have kept it off. I am a great fan of this way of eating and would encourage trying it."

As you could have guessed, Dr Michael Mosley swears by the 5:2 Diet, particularly for its health benefits and significant effect on weight loss. Not all diets work for everyone, so consult your GP before starting.


Is there really any advantage to any of the fad diets as opposed to just eating more sensibly? 

Eating sensibly is clearly a good idea, but the problem is that people find restrictive diets hard to stick to. As I mentioned above, a recent study done by Dr Michelle Harvie at Manchester University found that volunteers on a 5:2 diet, when compared to those on a more typical 1200 calorie a day diet, were more likely to stick to it, lost more weight and had improved biomarkers.


Disclaimer: The information on our diet and fitness pages is only intended as an informal guide and should not be treated as a substitute for medical advice. Gransnet would urge you to consult your GP before you begin any diet if you're concerned about your weight, have existing health conditions and/or are taking medication.


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