Calories The Truth About...

'100 calories.

'What does it look like?

'Well, it's two of these.'

It's about this much bacon.

One banana.

Two fish fingers.

And one quite small glass of this.

'They're all about 100 calories.'

As a nation, we're becoming obsessed by the numbers

stamped on every single packet of food we buy.

70 calories per serving.

80 calories a biscuit.

It says on most packs, an average adult can have 2,000 calories a day.

And all this counting brings a large helping of guilt...

I'm not sure I should've had the beer AND the fudge cake.

..to the things we love to eat.

You might say, "Why should I care about calories? So what?"

Well, as a doctor and as a scientist,

I think that is a very good question.

I'm not convinced it's all as black and white as we think,

so I'm going to uncover the latest science about calories,

and you're in for a bit of a surprise.

I'm going to show you how the food industry comes up with

the numbers on the packets,

and why they might be wrong.

The makers have said 370 calories per portion.

-Yeah.

-And we've found 410.

Three families will take our big calorie challenge.

They'll test what's really the best way to burn the calories we eat...

Mmm.

..and find out why they might be better staying at home

than going to the gym.

-What?

-LAUGHTER

And, my ultimate goal - I'll find out how we can all

cut our calories without giving up our favourite foods.

The answer might be double cream.

This is my kind of health messaging.

I want to get behind those numbers and find out

if they're really worth counting.

I want to discover the truth about calories.

But I'm not giving up any of the food I love.

As a nation, we buy 72 trillion a year.

Over a lifetime, each one of us will consume about 100 million.

We can't live without calories, but do we really know what they are?

They come from food. Something to do with energy, isn't it?

I should know what a calorie is, though, shouldn't I, really,

since we're always calorie counting?

It's a measurement of fat, right?

I suppose it's the fat and the sugar

and the content of your food, measured.

It's not something I think about a lot.

I just like to eat.

It's a measure of energy that's in a food.

That's what I'm led to believe.

Quite right, sir.

All those calorie numbers are a measure of the energy in our food

and the first thing I want to know is how far can we really trust them?

To find out, I need to follow calories all the way back

to their source.

And there are essentially just three different things that make up

all the calories that we eat.

I love the countryside and farms,

but in that romantic, slightly idiotic way

that people who live only in the city do.

As a reflection of how little I know,

I've never dug up a potato, which is what I'm surrounded by here.

But it can't be that hard, can it?

I'm going to eat my words.

HE GRUNTS

Right, that's got it.

Look at that.

Lovely bunch of potatoes.

I haven't done that particularly skilfully

but, nonetheless, here we have a potato.

And look at this. I mean, I don't know much about farming

but I do know what's going on inside here.

Look at that.

It's potato starch, a carbohydrate,

our first main source of calories.

So this is about 150 calories.

And in this field there are about 500 million calories

and all of these potatoes are going to a crisp factory

to be finely sliced and turned into crisps.

Half a billion calories in a single field -

it's mind boggling.

And all that energy comes from a source you might not expect.

It's the sun.

Take the apple trees in an orchard.

Every summer, they do this amazing thing where they take sunlight

and gas from atmosphere and they turn it into calories, they turn

it into sugar so they're locking up the sun's energy inside every apple.

I know I sound like some ludicrous apple advertisement,

but it's true - that's what's happening here.

We've got sunlight energy locked up in an apple in the form of sugar.

And that's true of all green plants.

They take sunlight and turn it into calories.

Even grass.

Cows munch it all day long and then almost magically transform it...

..into the second main source of calories in our food - fat.

Milk is about 4% fat.

Cheers, guys!

Finally, most of us eat meat from the animals themselves,

pig meat being a prime example.

But whatever thing you're eating from a pig, whether it's a kidney,

a liver, or the bit we all love, the muscle, as you can see there,

it's got protein in it and protein is our third source of calories.

So, in simple terms, all the calories we eat

come in just three types - fat, protein and carbohydrate.

But each of these takes a wide variety of different forms.

It's one of the things that makes our diet really rich and varied

but it also makes counting calories extremely complicated.

And this is at the heart of how the numbers on the packets

are worked out.

For carbohydrates, the food industry uses a standard figure

of four calories per gram.

For protein, it's the same -

four calories per gram.

And for fat, more than twice as much - nine calories per gram.

But this four, four, nine system uses average values.

The real figure depends on exactly what you're eating.

For instance, is your protein bacon or egg?

And it gets even more complicated

in foods with lots of different ingredients.

Like these popular takeaway meals.

They all have about the same number of calories.

But try guessing how many.

500?

750?

In fact, they all have over 1,000 calories -

half our daily allowance on a single plate.

But, for the food industry, guessing isn't good enough.

Every time you pick up a packaged food,

the label appears to tell you exactly how many calories are in it.

I want to find out how that's possible.

So I've got access to one of the biggest

suppliers of supermarket ready meals in the UK.

There's steam coming out over there

and some enormous spinning discs over there and production lines.

And just the odd familiar sight,

like a lasagne or a... or bangers and mash.

Every year, this place pumps out a staggering 28 billion calories.

You're making 800 kilos?

-750 kilos of...

-750 kilos?

-..of cheese sauce, yeah.

OK, so it's...it's like ten times your own weight.

And a bit more, yeah.

Oh, wow!

-That'll be 3,000 meals for this one.

-3,000 meals?

-Yeah.

And they need to calculate the calorie content

of every single meal.

-This whole kitchen area, we call it our big kitchen.

-Yeah.

And that's all it is, it's just a big kitchen.

And everything we do is about weighing.

Bigger scales, but more accurate scales than you would have at home.

As well as getting the weight right they also need to know

how much carb, fat and protein is in each meal.

We will test the fat content on each batch of sausages that come in

to make sure that they

are going to meet the calorie content of the final pack.

So, by weighing and testing the ingredients,

they have an average figure for the calories in each portion.

Remarkably, I've spotted a beef lasagne

that I eat quite a lot myself.

So I'm now actually...I'm making my lunch for next week...

..badly.

My own efforts aside, the folks here do a good job of

trying to ensure all the portions are consistent.

So I'm pretty confident the calorie count

will be in the right ball park.

But when these meals are put in their packets,

the labels will all display an identical number

that appears to be accurate to the single calorie.

And of that I'm going to take some convincing.

I want to find out how accurate those numbers really are,

so I've come to an independent food laboratory in Kent.

They've agreed to conduct a special test for us.

They're going to check the calorie count on some popular foods

that we've bought at random from different supermarkets.

John Griffin runs this lab.

-I'm naturally a bit sceptical, so I don't always trust labels.

-OK.

Can you tell us how many calories are in all this food?

By testing them, yes, we can.

We can tell you how many calories are in each of those products, yes.

First we have to take each product

and make a consistent mix of its ingredients.

It's brilliant. You saw it here first!

This is going to hit the high street soon -

pizza smoothie.

There's only one thing to do - have a taste.

It's pretty bad!

I'm not going to lie, that is pretty bad.

Hm, perhaps pizza smoothie won't catch on after all.

Anyway, this gloop goes off to be analysed in the lab.

It's separated into its different chemical constituents,

which are measured precisely.

This gives John an accurate way to check the calorie label.

-OK, so first up, a pork pie.

-Yeah.

I would suggest one of the best sources of calories that anyone

could ever, ever consume.

-So the makers have said 370 calories per portion.

-Yeah.

-And we've found 410.

-Yeah.

So it's a 40 calorie difference.

-So it's about 10%.

-Mm, that's about 10%, yeah.

Right, well, the pork pie has 40 calories more per portion

than the label claims it should have.

OK, first result, perhaps not a massive surprise.

The makers underestimating the calories.

Slightly underestimating.

Let's see if that... I want to see if that trend continues.

Next up, the can of beans.

The label said 162 per portion.

Our test said 175. That's 13 calories over.

And the beef dinner ready meal.

The label said 419 but our test said 458.

That's 39 calories over.

Cottage pie.

Per portion, which for me would be the whole thing, but

-they probably recommend...

-No, it is actually the whole, the whole thing.

-Is it? OK.

-That's a big cottage pie.

So they're, the manufacturer is saying 485

and we found less actually - we found 470.

Yeah, slightly less.

And the next four foods all had fewer calories

than the label stated.

-Last but not least, a pasta bake.

-OK, a nice ready meal.

It does, it does look good actually.

The manufacturers say 667.

You guys say 670, so that is bang on.

-That's very, very close.

-Very effective.

The pasta bake was spot on

but the others varied by up to 10% either side.

This may seem surprising, given how precise the labels appear,

but it is within government guidelines

because the number of calories will change slightly

from pack to pack and there's a limit to the accuracy of the test.

The good news if you want to count calories is that

even if the numbers aren't correct day-to-day,

over the long term you can trust they'll average out to be correct.

The next thing I want to know isn't about eating calories,

it's about burning them.

And here, the latest research is making us all think again.

The calorie is just a measurement of the amount of energy in our food

and, like most things in life, there's a sort of Goldilocks amount.

Too many and we get fat,

too few calories and we literally starve to death.

So the question is when does too few become too many?

How many calories do we actually need?

A humpback whale needs 100,000 calories a day

to power its massive body.

That's over a tonne of krill.

Whilst your pet cat needs only 270 calories or so,

a small tin of cat food.

And a mouse needs just ten calories, that's about three peanuts.

Now I may not like krill or cat food, but I still,

as an average man, need about 2,500 calories a day.

An average woman, about 2,000.

But whatever you're eating, there's one basic rule -

you only need as many calories as you use.

But we Brits are eating more than we use,

and that's why two thirds of us are overweight.

So, what's the best way to use up all those extra calories?

Exercise.

Exercise, I would guess.

Sustained walk.

-Go for a jog.

-Go for a jog, exercise, yes.

Right...up.

Over the head.

That's one...

'Hard exercise seems the obvious answer.'

Two...

We should've picked the lighter balls!

'But what if we've got it wrong?

'To get to the truth, I've come to meet Dr Jason Gill

'from the University of Glasgow.

'He's an expert in how we burn calories.'

-It's quite hard, isn't it?

-OK and then...

-And down.

Is this a good way of burning calories?

Erm, while you're doing this, you're burning quite a few calories,

but I think we wouldn't be able to keep it up for very long.

Two...

'There must be a better way, and Jason's going to help us find it.'

It's Saturday morning and perhaps understandably everyone else

is in bed, and I think there's really only one thing you can do

on a morning like this - have an enormous fry-up

with as many calories as you can put on your plate.

We've asked three Glasgow families to be our guinea pigs

in a unique experiment.

-Mmm! Can you smell the bacon?

-Yeah.

Yes, it's one of those smells that makes you hungry, isn't it? Mmm!

The families are going to start the day with a 600-calorie fry-up,

but after that, they'll spend their morning doing very different things,

and we're going to monitor how many of those breakfast calories

they're actually using.

You'll be burning yourself.

First, Jim and Elaine Morris.

They've got the toughest morning ahead - a workout at the gym.

Are you finding, as you get into your 40s,

that you have to start being a bit more aware?

I've never worried about weight at all and it's probably

-in the last three years, I'm really struggling to keep it off.

-Right.

Whilst you say you're struggling, I still think you're looking good.

-Ah!

-Right. Right, right, yeah!

A few miles down the road are Nick and Margaret Shenkin.

Look, Daddy's cooking!

You've never seen that before!

THEY LAUGH

The Shenkins will spend their morning doing housework.

And just around the corner with their 600-calorie breakfast...

-Smells good.

-..are the normally super-active Patrick and Roma Byrne.

Not today, though.

We've asked Patrick and Roma to sit on their backsides

and do absolutely nothing.

Do you feel you've got a bum deal, having to stay in this morning

playing a board game?

Yeah, we were a bit disappointed

because we thought we'd be the ones doing the exercise.

'We're just testing the adults.

'They'll all be wearing devices that measure how many calories they're burning.'

Ready... Off we go, then. 20 seconds.

That's it.

Jim and Elaine's workout will last an hour,

monitored by our expert, Jason.

Good job.

How can you get a sense, when you go to the gym and do stuff like this,

of how many calories you're burning?

The harder you find it, the more calories you're burning, so the

key indicators are whether you're feeling...if you're out of breath.

If you're breathing hard and finding it hard to hold a conversation,

then you're likely to be burning calories fast.

If you feel your heart beating fast,

you're likely to be burning calories faster.

The harder you feel it,

the more calories you're going to be burning.

How many calories per minute do you think...?

I mean, when they're working hard, they might be burning up to

about 20 calories a minute, but they're...

that's only on the times that they're working hard.

-Two to go, team.

-If you're not very fit, what happens,

you go very hard and you get tired.

So if we're really pushing ourselves,

we can burn about 20 calories a minute.

At this rate, we'd burn off a 600-calorie breakfast

in just half an hour.

Well done, take a breather.

The trouble is, most of us can't keep that up.

I am absolutely pooped!

So, to maximise the number of calories you burn, what you

have to do is be able to sustain the intensity for a long

period of time, so you might be better off going a little bit

easier for a longer period of time to maximise your calorie burn.

Nice and strong, standing up tall on top of the box...

So going all out at the gym might burn you out

before it burns up all your calories.

Halfway through, guys!

Now, at the other end of the scale,

how are the couch potatoes getting on?

Patrick and Roma, they're sitting at home. How many calories are they going to be burning for this hour?

Well, a bigger person might be burning up to about 90 calories,

a smaller person 60 calories an hour, just sitting down and doing nothing.

And that's because your... all your body's tissues need energy

just to operate, your brain needs energy, your liver, all the

body tissues require calories just to sit down and do nothing.

Being alive takes actually most of the energy that we burn in the day.

Sitting down and doing nothing probably burns about two thirds

of the calories the average person burns over the course of the day.

Really? That's most of our calories is just...?

-Just from sitting down doing nothing, just from existing.

-Just from existing...?

So we're ahead, aren't we, already? Without having gone to the gym,

without even getting out of bed, we're burning calories

-just every second of the day?

-We're burning calories. Absolutely.

So, just sitting around, Patrick and Roma

are still burning one or two calories every minute.

But at that rate, they'll take up to ten hours

to burn off their big breakfast.

Our third family, Nick and Margaret, are keeping busy with the housework.

Their level of activity will be changing all the time

as they do different chores throughout the morning.

We'll be back later in the programme to find out

which family are our calorie-burning champions.

We know a big breakfast is about 600 calories,

but what else has the same calorie count?

One portion of apple pie and cream...

and a bar of chocolate that I'd gobble up in about five minutes.

The least calorific food of all, celery, two large buckets of that.

And how many bags of peanuts?

Just one.

But what does that figure, 600 calories, actually mean?

When we tuck in, how much energy are we putting into our bodies?

Well, there's one way I can think of

to release calories from our food in a way we can see.

Right, that fits nicely.

'It's dangerous work, so I've got explosives expert

'Charlie Adcock on hand.'

Right, and just to make absolutely sure that this isn't

explosive cereal...

That is your standard puffed cereal.

'I absolutely love doing stuff like this.

'And now we add some liquid oxygen.

'It doesn't put in any extra energy, but it does make sure that

'every single calorie from the food is released.'

-Do you think that'll be sufficient?

-Is that all right?

That there, put that there...

OK, ready?

HE LAUGHS

This breakfast cereal inferno

is just 100 calories worth of food - spectacular!

THEY LAUGH

Right!

So there is a really enormous amount of energy in a...

in a fairly small bowl of cereal?

Yeah, we'll get the biscuits out.

'Next up, one of my favourite snacks, digestive biscuits.

'140 calories in these two.'

Ohh!

'Jet-propelled biscuits, whatever next?'

Wow!

'And the grand finale, two large packets of crisps -

'a scary 400 calories.'

This is the amount of crisps that a very greedy person might eat.

It might be the amount of crisps I might eat!

-Would this be a long movie...?

-Yes.

-Can you easily see this...?

-Yeah, I mean, we've all... we've all done that.

-Yeah.

-OK.

So now we add the lovely liquid oxygen...you can see there.

-Ready?

-I'd stand back a little bit.

Whoa-ho!

Ha-ha!

I'm not going to eat crisps for the rest of the day.

-No.

-Maybe not even tomorrow.

-No...

And then I'll be right back to business as usual!

That was spectacular.

We've completely melted an aluminium baking tray.

'Even as a scientist, I am astounded at the energy

'contained in just 400 calories, and most of us put at least

'five times that much energy into our bodies every single day.

'But we obviously don't have roaring fires burning in our bellies.

'Our body has to release all that energy in a very different way.'

To show you how, I've come back to medical school.

'What we're about to see is something truly fascinating,

'but not for the faint-hearted.

'Anatomist Clare Smith is showing me a real human digestive system.

'It's a vast alien-looking mass of tubes, and this is the stomach.'

I guess I thought it would be a really big bag,

if I think of how much I feel I can stuff into it.

So it is capable of stretching, so if you've eaten a large meal,

-with a couple of glasses of water, it is able to stretch.

-OK.

-It typically holds about one litre of fluid.

-OK, OK.

And then from the stomach, you then have a region here where

you're then going into the small intestines, and all of these

that you can see here,

this is all small intestines.

This is where the action happens, as it were.

So this is the small intestine running along here.

This is our special structure called the mesentery, which delivers

all the arteries and the veins to the small intestines so the arteries

are bringing nice fresh oxygen to the intestines and the veins

are taking our calories back to be used around the rest of the body.

The mesentery, I really like that.

I don't know if you can get the...

If you hold it up to the light, you can see the blood vessels.

'Despite its extensive blood supply

'and enormous length, the gut still takes hours to break food down

'into a form that it can be burned by the rest of our body.'

There's on average about six metres of small intestines.

-Six metres?

-Six metres.

-So, so three of me and a bit....

-And a bit.

-Standing on top of each other's head...

-As you can tell, it's all coiled up, erm,

in a way that doesn't get tangled.

-I'm just kind of amazed at how it all works.

-It's always amazing.

Every time you look at different parts of the anatomy

and you understand, it is always fascinating.

And the way our guts work means that not all calories are equal.

We absorb most of the calories in our food.

But some foods are rich in fibre, and fibre is different.

We only absorb about half the calories it contains.

The rest passes through our gut undigested.

And some fibre can absorb water in our stomach, making us

feel fuller for longer.

So, back to find out the results of our big calorie challenge.

We gave three families a 600-calorie breakfast,

and with the help of Dr Jason Gill from the University of Glasgow,

we've been monitoring how many of those calories

they've actually used throughout the morning.

They've all been doing very different things.

Elaine and Jim did a strenuous workout.

Nick and Margaret did a bit of housework.

While Patrick and Roma did... well, nothing at all.

So now it's time to see who's burned off their breakfast.

I'm going to start with Elaine and Jim.

LAUGHTER

So, Jim, you've burned 834, so you can have your lunch.

-Thank you very much.

-Elaine, you burned 729.

Yes!

What?!

So the main difference between that is the fact that Jim's heavier.

-That...

-Sorry, Jim.

All that difference can be explained by the difference

in your weight - you both worked equally hard.

Muscle is heavier, yeah, sure.

Three.

So by doing their workout, Elaine and Jim had both burned off

more than the 600 calories they ate at breakfast.

And Jim had burned about 100 calories more,

because the bigger you are, the more calories you use.

That's five.

Next, Patrick and Roma, who spent the morning on the couch.

So Patrick, although you did nothing between 9.15 in the morning

and 1.15 in the afternoon,

you burned more than your full English breakfast,

-you burned 640 calories.

-OK.

-Just by sitting still.

-Perfect!

-So that's the energy of being alive.

-Yeah.

-Roma, you burned half of that, 292.

In fact, less than half just sitting still.

-So again, it's the difference in your weight.

-Yeah.

Patrick is more than twice as heavy as Roma,

so that's why you're burning more.

Because you're bigger, you're able to eat more calories,

-you need more calories because there's more of you.

-Told you!

LAUGHTER

By sitting around all morning,

Roma didn't even get halfway to burning off her breakfast calories,

but I'm amazed to find that Patrick did get to the magic 600.

He's used twice as many calories as Roma just because he's twice as big.

Now, finally, Nick and Margaret.

They've spent the morning doing the housework.

So, Nick,

just doing housework between 9.15 and 1.15 in the afternoon,

Nick, you did 862 calories, Margaret, you did 629 calories.

-What?!

-LAUGHTER

-You didn't do half as much as me.

-So I need to do more housework now?

LAUGHTER This is also not good for me.

Nick, presumably you haven't been destroyed

by your morning of housework?

With some counselling later, I'll get over it, I think.

-I think I'll be fine.

-You'll rehydrate,

do some stretching, recover.

-So this was not an arduous morning for you?

-No, absolutely not.

Compared to your experience, Jim?

I feel physically actually quite weak

in terms of muscles and strength.

-So it's been quite draining.

-It's fascinating, isn't it?

Yeah. I guess there's two things here.

What...what Jim did was perfect for getting fit.

So what Jim did will make him fitter,

whereas what Nick did won't necessarily make him fitter.

But in terms of calories being burned, what Nick did wins out.

So moderate, continuous activity over a long period of time

burns the most calories.

Our experiment has been a real revelation.

I'd never have guessed that just doing the housework

would make Nick and Margaret our calorie-burning champions.

Or that even doing nothing at all,

Patrick would burn twice as many calories as Roma

just because he's bigger.

When it comes to how many calories we use,

our size and our lifestyle make more of a difference than we might think.

If you regularly eat more calories than you burn,

the simple truth is you'll put on weight.

Just 100 extra calories a day will add up over a year

to about five more kilos in body weight.

That's the best part of a stone.

And it's all too easy to consume those extra calories,

because eating is one of life's great pleasures.

We tend to indulge that pleasure

whenever we can and wherever we are, even when we're not really hungry.

-Wonderful!

-Thank you so much.

So we tend to think of food... as fuel,

but I don't need this paella as fuel.

I'm not sure any of these people need any of this food as fuel.

So we've come here to look at something else -

how our minds affect what we put in our mouths.

I've set up my own stall at Camden Market in London

to see a trick our mind plays

which can change the number of calories we eat.

WHIRRING

We've created one milkshake,

but packaged it up with two very different labels.

One suggests it's an indulgent high-calorie treat,

while the other claims it's a healthy low-calorie drink.

Now, could it be the case

that what's actually written on the bottle

is as important as what's inside it?

I want to discover

whether the number of calories we think we've consumed

can actually affect how hungry we feel.

So I'm going to play a trick on a group of identical twins.

We're separating each pair

and I'm giving one twin the shake with the high-calorie label.

They think they're having nearly 900 calories.

This is having a massive number of calories

at the beginning of the day.

It is actually... For a UK woman it is almost half your day's calories.

-Oh.

-So, sorry about that.

After my sales patter,

we're hoping they're fooled into feeling really full.

-I don't think I could drink that all, not for breakfast.

-OK.

-I think it's very satisfying, actually.

-Yeah.

This is very, very filling.

Now I'm giving the other twin exactly the same shake,

but with the low-calorie label.

They think they're having less than 200 calories.

A normal drink like this would be a lot more calories...

-I think for the taste.

-Yeah, it's lovely. Very nice.

What we're not telling them

is that both milkshakes are, of course, identical.

And it doesn't take long for one of the group who think

they've had a low-calorie drink to start feeling peckish.

It filled me up for about five minutes

and then I got hungry again after.

Two hours later, the results are convincing.

Not at all hungry.

Well, I still feel quite hungry.

I feel as if I haven't eaten anything at all this morning.

-Yeah, I'm really full.

-I'm ready for lunch now. I'm quite hungry.

I could pick at some food,

but I don't think I could eat like a full meal,

just some snacky, snacky food.

It depends what's on offer, but I think I could eat quite a lot.

Time to reveal the truth to our twins.

So the lie we told to you is that the Sensi-Shake,

guilt-free satisfaction, had 200 calories or a little bit less

and this shake had... the indulgence, decadence,

you deserve French vanilla

-had almost 900 calories.

-Whoa!

In fact, both shakes were the same and they both had 400 calories.

Did anyone guess what we were doing?

-No.

-No.

-Really?

-No.

Did you believe that it was a 200-calorie drink?

-Yes. Honestly, yes.

-Did you, yeah?

-Most definitely, yeah.

-Yeah.

Yes. I think, cos it just felt so light and everything,

although when you drank it you did feel full,

but afterwards, as I say, about 15,

10-15 minutes later, I was starting to feel hungry again.

Amazing!

Even when I revealed our trick,

they still found it hard to believe they'd been fooled.

-Chris, can I just ask you a question?

-Yeah.

Have these got...or do they have the same thickness?

Yeah, they're... It's the same product.

-It's the same drink.

-No!

-We put the same liquid in both bottles.

-All we've done is put different labels on.

-Wow!

It's brilliant, isn't it?

None of us can escape the food industry

tinkering with our brains, and they know that.

They know that the physical sensations

from our mouths and our guts,

the way we interpret those sensations, is massively influenced

by what's going on in our mind.

And the terrifying thing is, even when you know it's going on,

you still can't help being affected by it.

Alcohol is seven calories per gram, second only to fat in its calories.

Now, a single drink might not sound too disastrous.

A pint of 4% strength lager,

a double gin and tonic,

and a large glass of wine,

they're all under 200 calories.

That's less than a pint of cola, which is about 230 calories.

But pub calories can mount up.

A night out on three pints of lager, a couple of packets of crisps

and a small bag of peanuts, about 1,500 calories.

Not far off our entire daily allowance.

And, of course, it's not just the pub.

Our favourite treats tend to be really high-calorie food.

Mmm!

Calorie-dense, it's called,

packed with loads of fat and carbs.

Now, I'm not about to say that you should stop eating

this kind of food, cos frankly we've heard it all before,

we didn't listen then, we're not about to listen now,

but I do want to try and find a new way

of shaving calories off this kind of food.

A way that won't leave life feeling bland and joyless.

First, I've come to see how the professionals do it.

I've got access to the kitchens of a major supermarket.

Here product developer Kevin and independent chef Steve

are creating a brand-new low-calorie version of bangers and mash.

Their challenge is to strip calories out of this hearty meal.

My first surprise here is to see a chef at all.

I guess I imagined they were prepared by a robot.

It's really nice to see Steve, obviously not a robot.

The supermarket already makes a luxury version of bangers and mash.

This is the kind of luxury sausage and mash, I guess.

560 calories, 400 grams.

And presumably here... you've gone for taste?

Yeah, if you're having a sausage and mash,

you want your mash to be really creamy, indulgent,

and you want it to be restaurant-quality,

and that's what we aim to do.

OK, let's see how Steve reduces those calories.

I've always suspected there must be

a lot of junky additives and flavourings involved,

but Steve's doing none of that here.

Step one is to simply use half-fat sausages, saving 98 calories.

Step two, replace some of the potatoes in the mash

with carrots, parsnips and swede.

-Mix these two together?

-Yes, exactly.

OK. Another 28 calories saved.

Step three is a real surprise.

We blend our cooked mashed potato

with double cream rather than with butter,

cos double cream has half the level of fat.

Oh, really? But you've still got double cream

-in the low-fat meal?

-Yes, yes.

-Which presumably adds that kind of richness?

-Richness, yeah.

-Exactly.

Using a little cream and no butter actually saves another 50 calories.

But all this only works if the meal tastes good.

Now, like most people, I love bangers and mash,

so will it pass my taste test?

First, the luxury version.

Right, gravy.

Nice mouthful with everything on it.

-Mmm! I mean, that is really good.

-Good?

-It's good.

The moment of truth. I'm quite excited about this.

-Are you nervous, Steve?

-I'm not nervous, I'm totally confident. LAUGHTER

Totally confident!

So now I'll have the same forkful of the low-calorie version,

354 calories per portion.

That is really good.

That is really, really good.

The only really noticeable difference

-is it's not as salty.

-Yeah.

-Yep.

And that's the thing you can taste.

Let's just try a bit of the mash. Let's try a bit of the mash.

That is a really... Honestly, a really satisfying meal.

Steve has stripped a surprising 200 calories out of the luxury meal.

Now, he's done it by substituting some of the ingredients,

losing potatoes and cutting out butter.

But I really want to see if we can go one step further,

find a way we can really cheat the system,

cut the calories without giving up any of our guilty pleasures.

And we all have them.

Chocolate. THEY LAUGH

-Chocolate.

-Chocolate and bacon.

Sweets, that's what I do wrong.

-Yes, it's...

-Chocolates.

-Chocolates, yeah.

That's where your calories are.

All the things I buy and I shouldn't buy,

wrapped normally in shiny paper, and taste delicious.

Sweets, oil...and red meat.

-Pastries, creams and things like that, and chocolates.

-Yeah.

-Erm...but I wouldn't cut them out.

-Yeah, I wouldn't either, but...

-Feed the soul.

-You know, yeah.

-THEY LAUGH

You shouldn't have to give up anything, cos you know...

Anyway, we're just on the way for a Cornish pasty, aren't we?

-Yeah, let's go get a pie.

-Yeah.

I don't want to give up any of that stuff either,

so I've enlisted the help of nutritionist Amanda Ursell.

We're taking over a Glasgow restaurant for the afternoon.

And we're going to attempt what seems impossible -

to strip a load of calories out of their luxurious Sunday lunch

without changing a single ingredient.

Out front, we've got two tables of volunteers

who don't know what we're up to.

One will be served up the standard fare,

the other will have our low-calorie version.

And we're hoping they won't notice.

-So you're all hungry?

-Yeah, we're all starving.

-Yes.

-Are you really?

-Yeah.

-You don't have any idea what we're doing, do you?

-We don't.

-No, and I'm not going to tell you.

Back in the kitchen is chef Chris.

He's cooking three hearty courses -

soup, steak and chips and a full-cream dessert.

The way Chris normally cooks it,

the calorie count is a whopping 1,800,

pretty much our entire daily allowance.

But we've got five kitchen secrets to cut those calories,

and Amanda to keep an eye on the numbers.

-Can we do this?

-Yeah, we can.

There are some really clever little tricks you can do here,

but also at home, and that's the important thing,

whereby you can actually reduce the calories in your meal

without reducing the amount of food you're eating,

and, hopefully, make you feel fuller for longer afterwards.

So for starters it's chicken soup and our first kitchen secret.

We're not going to take anything out,

we're going to put something in - more liquid.

This won't reduce the calories,

but it should make the diners feel more full so they eat less later on.

So they're going to feel full for longer

and they're going to need fewer chips.

So soup is a great way of filling up,

feeling full for a long time and not having too many calories.

Next, the main course - time to start stripping out calories.

-So we want to make low-calorie steak and chips.

-OK.

Do you think that can be done?

-Would you know how to do that?

-Erm...no. LAUGHTER

I like fat, I like butter, I like salt,

so erm...this'll be a challenge.

I love this. You can reduce your calories

by just eating celery all day,

but I don't want to eat celery, I want to eat steak and chips.

And what's so good is we're going to show you

how to reduce the calories in steak and chips

without changing any of the ingredients.

I just love it.

This is my kind of health messaging.

First, the chips.

I'm amazed to find the calories can be doubled just by the cooking oil.

So here's our second kitchen secret.

Give the basket an almighty shake and bash.

So you can see the calories falling off those chips

back into the deep fat fryer.

That is awesome. OK.

'Our third secret is really more of a cheat.

'There's evidence that the bigger the portion,

'the more we're tempted to eat.'

So because these guys have had a big bowl of soup,

they don't need all these chips,

so one of the big ways of reducing calories is portion control.

I'm taking three chips off each plate.

Still looks like a big helping,

they're still going to be full, promise.

'Now, this is where it gets really interesting.

'The steak.

'When you start to cook it, its colour and texture begin to change,

'but beyond what the naked eye can see

'there's something far more important going on.

'Here, I've got some pictures of cooked steak

'magnified 400 times by a powerful microscope.

'This is how it looks when it's cooked for just a short time

'and served rare.

'A pretty solid mass. Our gut has to work really hard

'to break this down, and we don't absorb as many calories.'

You can sort of see that's...that's all very tightly bound together

by all this connective tissue, it's hard to digest.

'But look what happens when you cook the steak for longer.'

-Wow.

-It's really obviously broken up into these fibres.

'Cooking has started the process of breaking the meat down,

'so in our gut it's likely we use up fewer calories to digest it.

'So here's our fourth kitchen secret.

'To cut the calories you actually absorb from steak,

'don't cook it well done, cook it rare.'

So, one of the things we're hoping is that if our low-calorie table

has the rare steak it will actually take more calories to burn it.

-OK.

-So use calories by eating.

-It's nice, though, isn't it? It's really clear.

-Yeah, really neat.

'Out at the tables, how are our meals going down?'

-Lovely.

-I normally eat medium-rare, but that is gorgeous.

Yeah, I like that.

It's absolutely beautiful.

Just look at that, clean plates.

If they'd licked those boards they couldn't be any cleaner.

And one of our tables on the lower-fat, lower-cal tables

has actually left two chips,

so we're clearly not leaving people unsatisfied.

'Now for the biggest challenge yet.

'This is cranachan, a traditional Scottish dessert -

'oats, honey, whisky and masses of double cream.

'700 calories of pure indulgence.'

-A challenging pudding...

-To make healthier.

..to make healthier without changing any ingredients.

'But to lop off an impressive 100 calories

'we have a fifth and final kitchen secret.

'Thin air.'

So what we're going to use is this siphon, or cream whipper,

and this injects... There's a gas canister here,

and it injects gas into the cream and you get much more volume,

much more gas whipped into it than whipping it by hand.

So people will just simply be eating less,

but the portion should look just as big, that's the thing.

One, two, three.

Oh, you can really see mine is a lot less dense actually.

-How much? Like that?

-Perfect.

Great. OK.

Although yours looks nicer.

'So, time to add it all up.

'With our five kitchen secrets -

'the fuller-for-longer soup,

'the shake-and-bash chips,

'the reduced portion size,

'the rare steak...

'..and the aerated cream dessert -

how many calories have we managed to save?

'Well, that is spectacular.

'Without changing a single ingredient,

'Amanda's calculated that we've managed to strip out

'a whopping 360 calories from the meal.

'That's more calories than there were in the entire

'bangers and mash ready meal I tasted in the supermarket kitchen.

'I didn't think we'd manage half as much.'

We're just doing clever little things that overall

and over time could have a big impact on your weight.

-There you go... George, you have finished.

-I have.

So what do you think, are you all feeling full, satisfied?

-Very good, fantastic!

-Yeah.

You're not feeling like we fed you

-low-calorie nonsense?

-No.

-No, not at all.

I mean, I left two chips.

-Say again?

-I left two chips.

Someone left two chips, yeah, I was really impressed with that.

I was. I really... I'd had... Yeah.

So the key thing is, the number of calories

we saved you over the course of the meal compared to that table

-was 360 calories, OK?

-Wow.

So that's either another big portion of chips or three glasses of wine.

Wow! Three glasses of wine.

THEY ALL TALK AND LAUGH

The point is not now that you are all going to drink

three glasses of wine!

No. Oh, but I'll be cooking with that...

'Hmm, I'm not sure that's quite the right message.

'Oh, well, it's Sunday lunch.'

Cheers!

Over the course of this programme I've found out how far

we can trust the calorie numbers on the packets.

I've discovered the best way to burn the calories I eat.

And I've learned a few secrets

about how to cut the calories in my favourite foods.

Now it's time for me to put all this knowledge to the test.

Starting with breakfast, for one day, I want to see

whether I can get my calorie count more or less right on my own.

Right, so for the next 24 hours I'm going to try and exactly match

my calories out with my calories in,

but I'm not going to obsessively count them,

I'm just going to try and be calorie-aware.

So first up, my breakfast.

Now I've got my normal bowl of Cornflakes,

but to the flakes I've added bran,

so that's very fibrous, quite indigestible, it'll keep me

feeling fuller for longer.

It's good in other ways as well.

I've also got two eggs.

Eggs are quite low-calorie, they're relatively low-fat

but they're high in protein, so what that means is the protein is

very good at keeping you full for a long time.

So I'm hoping that this breakfast

will keep me feeling full until lunchtime.

I shouldn't need a mid-morning treat.

I'm just going to see if by thinking about it and being calorie-aware

I can get those two numbers, calories in versus calories out,

to match up.

The production team are counting the calories in my food

and I'm monitoring how many I use.

First, a 30-minute bike to work.

Then four flights of stairs, no lifts.

Working in the lab, standing and walking,

no sitting at all if I can help it.

Another walk to get some food.

That's 950 calories I've burned this morning.

OK, now, lunch.

This is not a low-calorie lunch, you know.

The lasagne is quite indulgent, it's not a low-fat lasagne.

I've got a load of veg but,

because I'm having the lasagne, I can't waste calories

on a soft drink full of sugar that won't fill me up,

so I'm going to have water.

More work. Getting a bit hungry now.

It's late afternoon. To be honest, my resolve's weakening.

I'm just not giving up my snack.

I'm on the go all the time.

I've been really active.

So far, that's 2,400 calories burned.

Cheers, mate.

A pub meal after work can't do any harm, can it?

Thank you, mate.

Erm...

Lovely.

That was good. I... I'm not sure I should've had the beer

AND the fudge cake but... I think I'm about right.

We'll see. Right.

No more food today,

but I'm still burning calories while I'm asleep

and by next morning I've burned 3,300 calories in 24 hours.

Now, the team have been working out - thank you - how much I ate.

Phew, big dinner.

1,813 calories for dinner.

Perhaps I could've guessed that. So my total is 3,400,

so I've eaten 100 calories more than I've burned.

I can believe that. It's a lot, though, isn't it?

A lot more than you might expect.

But the key thing is the balance,

and that is the truth about calories -

that if you eat more than you burn you will gain weight.

But that doesn't mean you have to obsess about every one

that goes in your mouth and every one that you burn.

By being conscious of them and by making these little changes,

lots of little changes to your lifestyle,

you can tip the balance in the right direction.

And in my case it looks like I'm going to have to work

a little bit harder.

Callipers.

Next time, the truth about fat.

We'll reveal the good, the bad and the downright ugly.

Oh, my God! I just find that really awful.

And why it might actually be good for us after all.