The 5:2 diet - What is it and how does it work?

For anyone who has tried everything and failed to lose weight, or you’ve shed extra pounds, only to pile them back again - this will be an interested read. A MORI survey in 2006 found that the average woman in the UK spends 31 years of her life dieting, yet the UK women are now the heaviest in Europe with UK men being the second heaviest in Europe.

We all know how you are supposed to lose weight: eat low-fat or low-carb foods, exercise more and never, ever skip meals. This has been standard dietary advice for decades and though it may work for some people, but the levels of obesity continue to soar. Overweight related diseases costed the NHS nine billion pounds in 2014 and the numbers are getting bigger! What scientists are seeing today is when we eat constantly, we use the carbohydrates and fat we’ve just eaten as a fuel, instead of tapping into and burning our stored fat! Constant grazing (snacking every one to two hours) may actually be what’s keeping us from losing weight! So is there an alternative to this constant eating? Based on the work of leading scientists from around the world, intermittent on/off fasting which is the principle of the 5:2 fasting diet (the 5:2 diet for short) might offer an exciting new alternative to standard dieting.

How does it work?

The 5:2 diet does not mean stopping eating entirely. It means reducing the amount you eat, but only for short periods of time.

With the 5:2 diet you eat normally five days a week and diet two days a week, cutting your calorie intake on those two days to a ¼ of their normal level. This means that on, say, a Monday and a Thursday you will eat 500 calories if you’re a woman, 600 if you’re a man. Once you get used to it, which normally takes only few days, it’s really simple and easy.

If you stick to this plan then you should lose around 1lb (half a kilo) a week if you are a women, slightly more for a men. And this will be predominantly fat loss around the middle.

Benefits of the 5:2 diet:

The main reason our bodies respond to fasting in the way they do is that we evolved at the time when fast and famine were the norm. Our bodies are designed to respond to stress and shock; ithas made them healthier and tougher. The science term is hormesis – meaning; what does not kill you makes you stronger. The benefits of fasting are thought to:

  • reduce blood glucose
  • reduce cholesterol/triglycerides
  • reduce blood pressure
  • reduce IGF1 factor (high levels are responsible for cancer development)
  • slow down the onset of dementia and Alzheimer's
  • this way of eating is very sustainable and pretty simple way of achieving your ideal weight and keeping it off, which not many diets do! No yo-yo effect here!
  • studies in Cambridge journal shown this way of eating works better than dieting every day of the week! The point is to stay as long as possible without food on your two fasting days, because when you feeling hungry this is the time when you are burning fat! Yes, that’s correct! Go on, let your tummy rumbles-it is a good thing! How many people do you know that died of hunger?

Fat loss is the key

What people sometimes forget in their drive to ‘lose weight’ is what they really want to lose is not the weight as such, but fat! Carrying excess fat is not just a bummer on the beach - it’s bad for your health! What is now known about the 5:2 diet is that helps to lose specifically fat around the middle – this is the visceral fat and it is particularly dangerous because it increases your risk of heart disease and diabetes. One of the recent studies shown that the 5:2 dieters lost fat 1.5 times quicker than the conventional seven-days dieters. Most of the calories you lose for fuel during fasting comes from fat stores and only a small amount from the muscles. One reason why it’s important to preserve as much muscle as possible is that muscle is metabolically active. Muscles burns calories, even at rest. Actually, muscles burn seven times more calories than fat while at rest! Because the 5:2 diet promotes fat loss and minimal muscle loss, this in turn helps to minimise the reduction in metabolic rate, which is the major difference between the 5:2 diet and the other diets out there.

How is the 5:2 different from other diets?

  • The 5:2 diet retrains your eating habits. Habits such as regular over-consumption of food, eating overly large portions, having too many fatty and sugary foods or habitual snacking (and often all of these). The 5:2 diet gives you much needed break from your normal eating habits each week and helps you to develop vigilance and awareness of what you eat. These are vital skills to put you in control of what you eat, therefore, your weight.
  • It develops your appreciation of food. When did you last feel hungry? Honestly? Significantly cutting calories twice a week will help you to relearn how hunger feels and what a ‘normal’ serving looks like. You will learn to eat more slowly, appreciate smaller amounts and really enjoy food on both two restricted and non-restricted days.
  • The 5:2 diet boost your dieting confidence, which suffers a lot over the years! Basically for two days every week you have opportunity to learn to resist temptation. This is the key dieting skill that you will need to practice until it becomes a habit!

A leading doctor has said: ‘There is nothing else you can do to your body that is as powerful as fasting.’

As a matter of fact, this diet acts as a mini detox on a weekly basis. Fasting seems to be a stop that re-set the clock!

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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Sutton, Surrey, SM1
Written by Angelika Cutuk-Short, MSc Functional Nutritionist / Hormone and Weight specialist
Sutton, Surrey, SM1

Angelika Cutuk-Short is a registered Bsc, MSc nutritionist and NLP practitioner. She has been in the nutrition industry since 2007. She specialised in the weight loss management and works with people who have been struggling with weight loss for a long time now, those are the people she can help the most.

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