B00AFYX78I EBOK (5 page)

But as soon as I started reintroducing the breads and
potatoes into my diet (we moved to Barcelona, where ‘pan con tomate’ is served
everywhere, and  potato-packed tortilla is the default vegetarian option), I
was no more able to resist them than I was before.

I boomeranged right back to my previous weight. And then
some. Among the slim young things of one of Europe’s funkiest city, I felt like
a terrible frump. Which made me eat more.

The more extreme diets - Cabbage Soup, Maple Syrup,
Grapefruit - cut your calorie intake by restricting your diet, but also your
social life. Would anybody want to live on grapefruits for the rest of their
life? I think it would feel like a very, very long life.

And as for cabbage soup… let’s not go there.

But the bottom line about most diets is that they take the
pleasure out of food.

The basic dieting equation:

X (the energy your body needs to
function) minus Y (3,500 calories) =

Z (a weight loss of 1lb or 0.45kg)

As
you can tell, algebra has never been my strong point. But simple arithmetic I
can
do.

And it works like this. It’s estimated that to lose a pound
of weight, we need to have a ‘deficit’ of 3,500 calories – the same figure
applies to putting weight
on.
If we eat 3,500 more calories than we need
– over any period of time – we will potentially weigh a pound (0.45 kg) more.
That helps to explain why even eating one extra biscuit a day, for example, can
lead to significant weight gain over a year. On the positive side, it also means
small cuts in our daily consumption – not taking sugar in hot drinks, say – can
have impressive cumulative effects.

So, to become a pound (0.45 kg) lighter, you must eat 3,500
less calories than your body needs (throughout this book, when I refer to
calories, I’m referring to what nutrition labels list as kilo calories or
kcal.). Eat 35,000 calories fewer and that’s ten pounds (4.5 kg) gone.

That’s the theory. As with everything in the diet/nutrition
world, it’s not quite that simple. A calorie is a simple measure of energy, but
it doesn’t reflect the different ways the body processes calories from fat,
carbohydrate and protein, which can affect how we store excess calories.

Another factor in how much weight we might lose is exercise
– we’re encouraged to exercise as part of a healthy living plan, but muscle
mass is denser and heavier than fat.

 For the sake of simplicity, let’s work with the 3,500 as it
gives us a baseline. Whatever the exact numbers, it’s very clear that to lose
weight we must create a deficit to make our bodies turn to our fat stores for
energy. The question is, how do you achieve this deficit?

For my entire dieting life, I’ve assumed that you must diet
all
the time:
and that’s where it’s become tricky, because it’s so hard to deny
ourselves the foods we’re programmed to crave. It’s even harder to keep to a
regime when all you can see ahead is more deprivation.

All
that time, there has been another way

5:2
– and all other types of intermittent fasting/calorie restriction – offer a
radically different, though surprisingly obvious, solution. If you reduce your
calorie intake more drastically, but for a limited period, you’ll lose the
weight. Because you aren’t denying yourself the pleasures of food – or the
social aspects of eating – the whole time, you stand a much higher chance of staying
on track. Plus, knowing the medical benefits motivates you still further. It’s
win-win.

My other half is a chef, and
having smaller portions or calorie counting 7 days a week just ain’t going to
happen, but I can manage 2. To my mind the big benefit is the 5:2 is far easier
to fit round family life/socialising etc. as one doesn't have to worry about it
for the vast proportion of the time.

Sarah, 49

Doing
the math(s)

So
let’s look at it in purely numerical terms.

A moderately active, average-sized woman needs 1800-2000
calories per day to maintain her weight, while for men it’s 2300-2500. This is
known as the Daily Calorie Requirement (there are instructions for calculating
your own DCR in
Part Two
).

Let’s
use Miss Average as an example for now.

2000 (DCR) x 7 (days of the week) =

14,000 (total calorie needs to maintain current
weight)

Conventional Calorie-controlled diet:

If you’re overweight and want to lose a pound a week (which
many doctors suggest as a ‘sustainable’ weight loss), you’d have to lower your weekly
intake by 3,500 calories i.e. consume a maximum of
10,500 in one week –
which is 1,500 calories per day.

This is how you’d aim to achieve that on
a traditional calorie-controlled diet, where you’re eating the same every day.

7 days at 1,500 calories per
day

Weekly Total = 10,500 calories

That’s
actually a higher allowance than many calorie-controlled diets, but it still
means calorie counting every day for a very long period: with a stone (14 lbs
or 6.4 kg) to lose, for example, you’re talking about fourteen weeks of
counting and deprivation. If you’re looking to lose four stone (25 kg), you’re
facing over a year of constantly obsessing over what you’re eating. That’s
boring, anti-social and a constant reminder that you’re ‘different.’

5:2 Diet

Let’s
compare it to 5:2: you’re cutting the calories more drastically for just two
days of the week (or three or one, depending on what suits you best). The rest
of the time you eat normally.

5 x Feast Days (approx. 2000 calories) =
10,000 calories

2 x Fast Days (500 calories = 25% of DCR)
= 1000 calories

Weekly total: 11,000

In
this example, you’re eating 500 cals more than you would by calorie counting
every day. This would potentially slow down weight loss slightly, though many
dieters I’ve spoken to say that on Feast Days, they tend to naturally eat a
little less – so I suspect it evens out.

But
there’s another crucial point about 5:2 – you don’t actually need to calorie
count the rest of the time. You can eat what you feel like.

Many
people really can’t believe this at first, but research has shown that ICR
(intermittent calorie restriction) doesn’t lead to bingeing. On average, ICR
dieters eat between 95% and 125% of what they need – but even the higher figure
isn’t enough to cancel out the fast days.

I can fast because I know next
day I can have chocolate AND wine if I so wish. Funnily enough, because I can,
I don't binge.

Myfanwy, 49

My ‘problem’ is that having
eaten low calorie foods for most of my life it’s hard to eat anything like
‘normal’ calories on my ‘feasting’ days, so will often eat a couple of biscuits
or have a glass of wine to make up the calories!

Linda, 63

Of
course, if you decide to do the diet more often than two days a week – every
other day, for example, (known as Alternate Daily Fasting or ADF) – the
calorie deficit increases. So fasting on Sunday, Tuesday and Thursday looks
like this:

4 x Feast Days - approx. 2000
calories – 8,000 calories

3 x Fast Days (25% of daily
energy needs) = 1500

Weekly Total: 9,500 calories

Many
people on ADF do stick to three Fast Days – but it’s advisable that you don’t
fast more often than every other day. There’s a risk you’ll get fed up with
restricting so often – what you’re looking for is a sustainable lifestyle.

What
are the Fast Days like?

I
won’t lie – they can take some getting used to at first. We’re so used to
eating before we get anywhere near experiencing hunger that it can be odd or
even alarming to begin with when our appetite kicks in.

It's easy, and the more you do
it, the easier it gets. Eat some protein on your restricted days, give the
regime at least a month before considering if it works for you or not.

Paul, 47

I like the discipline on two
days (and the self-awareness of slight hunger discomfort), combined with complete
freedom the rest of the week. I’ve learned to enjoy the empty stomach feeling.

James, 43

500
calories for women – and 600 for men – is enough to keep you from feeling
unwell, especially if you choose your foods wisely: there’s much more about what
to eat in
Part Three.

Plus, believe it or not, hunger isn’t a huge deal. When was
the last time you felt hungry, instead of thirsty or bored? Allowing yourself
to experience hunger – and to see how little food it takes to feel full again –
is a huge help when you want to have more control over your appetite and your
eating.

Finally, and crucially,
it’s only one day at a time
.
In contrast to the daily monotony of ‘normal’ diets, with 5:2 you’re only
having to limit yourself for a couple of days (and they’re not consecutive). It’s
so much easier to say no to a cake or a glass of wine when you know you can
have it tomorrow than it is when your diet feels like a very long punishment
for being fat.

Weight
loss is only the start…

So
the maths makes sense, and most people find this diet far easier to stick to
than conventional calorie-controlled regimes (see the links list for research
backing this up).

But
5:2 is about so much more than weight loss. The evidence that fasting brings
physiological and mental changes is growing all the time. As we’ll see in the
“science bit” in
Chapter Three
, the secret’s in your cells and your genes.

But before that, find out how I got on in the first week of
my
fasting experiment…

First
Fast – of many?

Mood: excited, apprehensive,
unsure

I’m
taking the plunge. Fasting is the future… maybe.

My boyfriend is sceptical, and other friends (who haven’t seen
the programme) are also dubious - one talked in dark tones about ‘starvation
mode’ where your body responds to cutting calories by slowing down all its
systems to keep you alive: that could mean when you go back to eating normal
amounts, you put even more weight on.

But from my research online, the jury’s out about whether that
mode even exists. And if it does, then fasting one day at a time means you’re not
at risk of a metabolic ‘go slow.’

If in doubt,
Google
it…

As
I am self-employed, and work from home, my first response to pretty much all my
daily decisions is to Google them. Seriously. It’s not something I’m proud of -
recently I’ve asked the big G where to rent a holiday cottage, how to answer my
brand new but complicated mobile phone, and whether it’s true that Marilyn
Monroe was severely flatulent (apparently so). So it’s inevitable that I’m
doing the same with 5:2.

The TV show was fascinating, but I still have lots of questions:
how many meals a day should I eat on the ‘fast’ days - is it better to eat one
or three? What should my calorie target be on those days? Can I
really
eat as much as I like on my unrestricted or ‘feed days’? Apart from eating
slightly less, is the diet different for women?

I fully expected to find lots of sites dealing with this
approach, but what’s out there doesn’t seem to be aimed at the layperson – I
found either scientific papers or pretty intense body-building sites.

What I did read seems to back up the potential health benefits,
though. Plus, having worked as a producer at the BBC myself, I know how
stringent the guidelines are for making any health claim on a programme, so I
am certain the ideas ‘Horizon’ featured will be sound – so I’m giving it a
whirl.

Doing the Math(s)

The
first thing I have to do is work out roughly how many calories I need to
maintain my current (over)weight.

I
could use the average fast day limit of 500 calories. But I’m keen to know
exactly where I stand, so I use the calculators on the MyFitnessPal website.
It’s a very neat site which, so far, has mainly helped me record exactly how
much I’m eating - too much - and made me feel guilty about my weekly intake of
cava (what I really need is an app that stops me opening the bottle in the
first place).

My first step is to work out my Basal Metabolic Rate - an
estimate of how many calories I need just to get through the day. The
calculator tells me it’s 1,365 which is a terrifyingly low figure…

Then I realise that’s based on just keeping all your body’s
systems ticking over. So I must factor in my activity level using the Harris
Benedict Formula - which sounds a bit like an episode of Sherlock. Because I do
some light exercise, I multiply my BMR by 1.375 which gives me… a more generous
1876.87.