Intermittent Fasting and 5:2 diets - what's the deal?

Intermittent Fasting – also known as the 5:2 diet, the 2 day diet, the overnight diet or the Fast Diet…
As most of my clients know, I have always been very cautious about the idea of fasting, instead preferring the ‘eat little and often’ line of nutritional thought.
But nutritional science is ever changing and I am intrigued and excited about the potential health benefits of this new, perhaps safer method of fasting, known as intermittent fasting.

The idea is that for two days a week you restrict your calorie intake to 500-600kcals a day and the rest of the time you eat a normal diet.

There are different versions of Intermittent Fasting and here I take a look at three of the most popular ones doing the rounds at the minute.

The Fast Diet

Who? Medical journalist Michael Mosley highlighted Intermittent Fasting on the BBC Horizon programme and his experiences last year after begin told by his GP that he was pre-diabetic and overweight. Michael has written this book with award winning food and fashion writer, Mimi Spencer.
What? The Fast Diet advocates eating 500kcals for women and 600kcals for men, two days a week – they recommend doing the fast days on non-consecutive days. On your fast days, you eat low GI and protein and the rest of the time you eat what you like. The book gives 10 days food plans for fasting days.

Vital Nutrition’s Verdict?

As the Fast Diet does not cut out any food groups and advocates a low GI diet on non-fasting days, this seems a healthy approach to intermittent fasting. Fast days combine protein and low GI foods to help keep hunger at bay and Michael & Mimi recommend skipping one meal a day – breakfast or lunch.

The Two Day Diet

Who? Dr Michelle Harvie, a dieticain from the Genesis Breast Cancer Prevention Centre in Manchester and Prof Tony Howell, professor of medical oncology at the University of Manchester.
What? A calorie restricted diet for two days a week a week. Two days of the week you follow a low-carb plan, and the rest of the week you can eat anything provided you eat relatively sensibly (no big greasy kebabs with piles of chips!). On the diet days, you can only consume certain foods, such as fruit, vegetables, water, milk or Bovril.

Vital Nutrition’s Verdict?

Although there is some great stuff in this diet, e.g. spread your kcals out between 3 meals, so you do not skip meals (might be easier than the thought of skipping a meal), I am not so keen on the idea of eating Muller Light yoghurts, diet drinks and cordial. There’s also a lot of milk on this version of intermittent fasting, so although the research is interesting, I think there are better ways of doing the 5:2 diet.

Eat Fast Slim

Who? Nutritional Therapist Amanda Hamilton
What? Amanda looks at different methods of Intermittent Fasting – the 5:2 method, 16:8 version and juice fasts. She compares each and helps readers decide which is likely to fit into their lifestyle best.

Vital Nutrition’s Verdict?

A comprehensive look at different fasting methods, with plenty of menu ideas for each diet. Amanda takes a healthy, balanced approach to intermittent fasting, advocating real food – no processed crap or fizzy drinks – this gets the thumbs up from Vital Nutrition.

Intermittent Fasting is not for everyone, but the research that backs up this new way of nutritional thinking makes for compelling reading. Don’t forget that if you have health issues, are pregnant, under 18 or type 2 diabetes, this diet is not for you. Check with your GP if you are unsure.