The 5:2 diet - fact or fad?

You may have heard about the now famous 5:2 diet and wondered what all the fuss was about. Like many weight loss diet concepts, it has enjoyed a lot of media fanfare, but has also had its share of critics who have labelled it merely a fad. As is often the case with ‘celebrity diets’, it may not be the universal answer for all, but there are some useful principles that can make it a very healthy alternative for some.

The diet first attracted serious attention when it was the subject of a popular television documentary in the UK in 2012. That appearance and the subsequent best-selling book have garnered passionate followers who testify to its value as an effective weight loss method. The fundamental practice behind the diet is to eat a fairly normal healthy diet on five days of the week and on the other two (consecutive or non-consecutive) ‘fasting days’ you are limited to 500 calories for women and circa 600 calories for men.

The concept of fasting is not exactly new; various religions have promoted the idea of fasting as a symbol of self-denial or cleansing for centuries. Perhaps what is different in the case of the 5:2 is that it has been refined into a more structured regimen that can be followed as a long term practice for weight management.

So what can you eat on the 5:2?
It isn’t just the fasting aspect that matters, there needs to be a balanced and healthy approach to the foods that are eaten on non-fasting days too. For example, on the fasting days, where there is a calorie limit of 500/600 cal, you need to be careful that this target isn’t achieved by simply having a cup of coffee to replace breakfast and lunch. A more desirable option would involve salads, vegetables, white fish, eggs, lean chicken and soups spread across the day.

The key issue to remember on the fasting days is that portion sizes using any of these ingredients will be small! After all, 500/600 calories only amounts to a quarter of a normal daily calorie intake. You can, however, have as much water as you like, which may help stave off the hunger pangs! Similarly, on the 5 normal diet days it is important to eat a balanced diet in order to get the most benefit.

Here's a taste of what sort of meals will help keep you within fasting calorie limits.

What benefits does it claim to have?
Perhaps one of the attractions of the 5:2 is that it addresses the issue of overwhelming abundance, choice and temptation present in our modern western culture. Our minds and bodies have become accustomed to having hunger constantly satisfied whenever we feel the urge. The 5:2 diet offers a moderate way to recapture a heightened sense of ‘listening’ to our body’s hunger and satiety signals.

There is some anecdotal evidence that the cumulative effect of the periodic fasting will result in a reduced desire to over-eat even on non-fasting days. The jolt it gives to the system may also be helping to ‘reprogram’ our brains to be more mindful of what we are eating and to raise awareness of the need to savour and enjoy food, as opposed to shovelling it in.

Of course, many would suspect that the opposite may be true and after a day of fasting there would be an even stronger urge to binge uncontrollably, which would lead to weight gain, not loss. Devotees, however, report that they generally tend to see a reduction in overall intake over time, with a greater sense of control and satisfaction and less o the impulse to constantly grab snacks. 

A word of warning
Like any diet, it is wise to consult your medical professionals before making any radical lifestyle changes. Those with diabetes need to be particularly wary of any diet involving fasting, as this may have adverse effects. Have you tried the 5:2 diet? We'd like to hear from you if you have. Leave a comment below or email us at

Other popular diets: The Mediterranean diet and The Paleo Diet