I wake up at 8am and drink 500ml of water. This is all I’ll have before I get to work and knock back another litre, this time with a scoop of superfood greens mixed in and a steaming cup of green tea as a chaser. There will be more tea at 11am. It’s only after I’ve pushed through my lunchtime gym session – with minimal assistance from 10g of BCAAs, to stop muscle mass loss – that I’ll have my first meal of the day, a giant plate of protein and veg that’s also my first solid food in 16 hours.

Until recently, I’d have filed this eating plan alongside the cayenne-pepper-and-syrup diets you read about in celeb mags – sure to slow my metabolism to a crawl, force my body into starvation mode, destroy my hard-earned muscle and drive me insane. Everyone knows that breakfast is the most important meal of the day and that frequent, small meals are the key to stoking the metabolic fires and keeping fat loss on track, right? Well… not necessarily.

A number of big names in the nutrition world have come over to the idea that intermittent fasting, far from being hippie nonsense, can actually be beneficial. They suggest it can change the way you think about eating, help you manage your hunger and give you that final nudge towards a single-digit body-fat percentage. There’s evidence from studies on animals that it might help reduce blood pressure, increase cell repair and even increase lifespan.

On the flipside, it’s certainly not for everyone. People who’ve had eating disorders, for instance, should steer well clear. Many trainers still regard it as a bit of a gimmick. Who’s right? My green tea binge is part of my attempt to find out.

First, here are the most popular fasting practices being used today. Read on to find out how I got on as I became MF’s fasting guinea pig for the month.

FAST # 1

24-hour Trial Dr John Berardi recommends starting at 10pm, eating your last meal just before that time. Drink water and green tea at intervals throughout the following day, and take 10g of BCAAs. At 10pm, eat a small carb-free snack before bed before going back to normal eating the next day.
More info johnberardi.com

FAST # 2

16/8 Sometimes known as ‘Leangains’ after the term was popularised by author Martin Berkhan, this simply means restricting your eating window to eight hours a day. Most people go without food from 9pm to 1pm, train at lunch and then eat two to three large meals within the next eight hours. Not for beginners.
More info leangains.com

FAST # 3

Periodic Exactly the same as the 24-hour trial, except you don’t start at 10pm – you simply do it using whatever interval suits you, such as from breakfast to breakfast. Berardi does this when he’s travelling and can’t find quality meat and veg.
More info johnberardi.com

FAST # 4

20/4 Popularised by Ori Hofmekler as the Warrior Diet, since it’s supposed to emulate the feeding patterns of Roman centurions and Spartan soldiers. Possibly the easiest to follow, although you might get hungry throughout the day – and it’s tough to eat ‘clean’ when you’re knocking back 2,000 calories in one sitting.
More info warriordiet.com

On the next page: MF’s fasting experience