0:00:02 > 0:00:03Hello, and welcome to Bang.
0:00:03 > 0:00:05We're here to bring you the science behind the headlines.
0:00:05 > 0:00:08We've been busy researching the issues that affect us all
0:00:08 > 0:00:09and have a real impact on our lives.
0:00:08 > 0:00:11It seems like food is always in the news.
0:00:11 > 0:00:14What's good for you, what's bad for you, the latest diet fad,
0:00:14 > 0:00:16and, of course, the latest health scare.
0:00:18 > 0:00:21In the past, things like fat and salt have come under fire,
0:00:21 > 0:00:25but nowadays it seems to be sugar that's in the dietary dock.
0:00:26 > 0:00:29Sugar is a billion-pound industry.
0:00:29 > 0:00:32In the UK we consume over two million tons of the stuff
0:00:32 > 0:00:36every single year, often without realising it.
0:00:36 > 0:00:39It causes tooth decay, but what else?
0:00:39 > 0:00:42Obesity, diabetes, heart disease.
0:00:41 > 0:00:44- So do you monitor the amount of sugar in your diet?- No, I love sugar.
0:00:46 > 0:00:47It gives you a boost for a wee while
0:00:47 > 0:00:49and then you have a big comedown from it.
0:00:49 > 0:00:51When it comes to children, sugary drinks,
0:00:51 > 0:00:53too much sugar makes them hyper.
0:00:53 > 0:00:55Too much is bad for you, really.
0:00:55 > 0:00:59I take a lot of sugar in stuff, like in my tea I have, like, four sugars and stuff.
0:00:59 > 0:01:01My wife has an extremely sweet tooth.
0:01:01 > 0:01:03She can eat a box of chocolates at one sitting,
0:01:03 > 0:01:05and I'm talking a big box of chocolates.
0:01:05 > 0:01:09Coming up - the pros and cons of all things sweet.
0:01:09 > 0:01:13Liz finds out why we have such a sweet tooth.
0:01:13 > 0:01:17Without sugar, our cells couldn't do their jobs,
0:01:17 > 0:01:19our muscles wouldn't work,
0:01:19 > 0:01:22and most importantly, our brains simply wouldn't function.
0:01:22 > 0:01:25We meet the doctor horrified to find his diet
0:01:25 > 0:01:28has given him fatty liver disease.
0:01:26 > 0:01:28It's maybe a wake-up call
0:01:28 > 0:01:31that actually I need to change my lifestyle,
0:01:31 > 0:01:34because this will only get worse, if I don't do something dramatic.
0:01:36 > 0:01:39And Maggie discovers that sugar is also a secret weapon
0:01:39 > 0:01:41in our fight against infection.
0:01:40 > 0:01:42What I really love about this is that it's so elegant.
0:01:42 > 0:01:46It's a neat, simple idea that addresses a massive problem.
0:01:48 > 0:01:53Tonight on Bang Goes The Theory - sugar.
0:01:54 > 0:01:58- Right, do you use sugar at all? - Yes, I do. White sugar in my tea.
0:01:58 > 0:01:59- White sugar.- OK.
0:01:59 > 0:02:02So, if you're looking at these sugars,
0:02:02 > 0:02:04do you feel that any of them
0:02:04 > 0:02:07are healthier or better for you than others?
0:02:08 > 0:02:13I should imagine brown sugar's probably more healthy for you.
0:02:13 > 0:02:15I'd probably say generally the darker the food is
0:02:15 > 0:02:17I'd generally associate that with health,
0:02:17 > 0:02:20so I'd probably say probably the darker sugar.
0:02:20 > 0:02:24I would probably say the honey and the brown sugars.
0:02:24 > 0:02:25They're less processed.
0:02:23 > 0:02:26Would you use any particular sugar rather than another
0:02:26 > 0:02:30because you might think it was either better for you or healthier?
0:02:32 > 0:02:33No, cos all sugar's the same,
0:02:33 > 0:02:35there's obviously just different bleachings.
0:02:34 > 0:02:37- I do tend to buy brown sugar rather than white sugar.- And why is that?
0:02:38 > 0:02:41I don't know why. I think it just looks more healthy.
0:02:45 > 0:02:49So, first in the dock, white sugar - sucrose.
0:02:52 > 0:02:56Is it really as processed, bleached and unnatural as people think?
0:02:56 > 0:02:59Over the past few months,
0:02:59 > 0:03:02thousands of tons of sucrose
0:03:02 > 0:03:05has been created just under the ground here,
0:03:05 > 0:03:08and it's been created inside...
0:03:08 > 0:03:10these fellas.
0:03:12 > 0:03:14Sugar beets.
0:03:14 > 0:03:22Over 7,000 farmers produce 9 million tons of beet in the UK every year.
0:03:23 > 0:03:26It's one of the most profitable crops in the country.
0:03:26 > 0:03:32Incredibly, this root vegetable could be almost 20% sugar by weight,
0:03:32 > 0:03:36but the trick is getting that sugar out.
0:03:38 > 0:03:42I want to make some granulated white sugar myself.
0:03:42 > 0:03:46Essentially, I just need to get rid of all the bits of beet
0:03:46 > 0:03:47that aren't sucrose.
0:03:50 > 0:03:52It's stored inside the cells of the beet,
0:03:52 > 0:03:56so we need to chop it up to expose as many cells as possible,
0:03:56 > 0:03:59then drop it in hot water.
0:03:59 > 0:04:01I'm actually going to turn that off,
0:04:01 > 0:04:02because I don't want the water boiling,
0:04:02 > 0:04:05because then it starts destroying the cells of the plant.
0:04:05 > 0:04:10I just want it hot enough that the sugar that's within those cells
0:04:10 > 0:04:13just happily diffuses out into the warm water.
0:04:13 > 0:04:1570-80 degrees is about right.
0:04:15 > 0:04:19While I leave that to simmer, this exact process is happening
0:04:19 > 0:04:22just across the field on an industrial scale.
0:04:23 > 0:04:26This is the Wissington Refinery in Norfolk.
0:04:28 > 0:04:31It's the largest beet sugar factory in the world.
0:04:31 > 0:04:34The beets are delivered by the truckload
0:04:34 > 0:04:36to that massive pile over there,
0:04:36 > 0:04:38where high pressure water
0:04:38 > 0:04:42forces them to flow up those two huge metal pipes.
0:04:42 > 0:04:44I guess from there it's a bit of a log flume.
0:04:44 > 0:04:46They float down and round the corner,
0:04:46 > 0:04:48being washed of stone and soil.
0:04:48 > 0:04:50And actually the stones and soil
0:04:50 > 0:04:52are then sold off as topsoil and aggregates.
0:04:52 > 0:04:53Nothing's wasted.
0:04:53 > 0:04:57Maybe the fun stops for the beet at that point,
0:04:57 > 0:05:00because in there is a vast chipping machine
0:05:00 > 0:05:05and it cuts the beet into these fine little slices,
0:05:05 > 0:05:10which have plenty of surface area for extracting sugar and...
0:05:10 > 0:05:11taste OK.
0:05:11 > 0:05:13In these rotating drums,
0:05:13 > 0:05:17the sugar diffuses out into hot water.
0:05:18 > 0:05:20Just like it has in my saucepan.
0:05:20 > 0:05:24What's left is a dirty, sugary juice.
0:05:24 > 0:05:27That's beginning to taste very sweet.
0:05:27 > 0:05:32So now I've got rid of almost everything about those sugar beet that isn't sugar.
0:05:32 > 0:05:33I say almost everything,
0:05:33 > 0:05:37because in this dirty water here,
0:05:37 > 0:05:39it might be about half a kilo of sugar,
0:05:39 > 0:05:41but also there's a few proteins and a few minerals
0:05:41 > 0:05:45and little bits of soil that I don't really want.
0:05:45 > 0:05:47I can easily get rid of all that muck
0:05:47 > 0:05:50with the help of some milk of lime
0:05:50 > 0:05:54and a bit of carbon dioxide from a fizzy drinks maker.
0:05:56 > 0:05:59Between them, they combine to make chalk,
0:05:59 > 0:06:01which helps sink everything to the bottom.
0:06:04 > 0:06:06That's settled out beautifully.
0:06:06 > 0:06:09The chalky deposit at the bottom there
0:06:09 > 0:06:13has pretty much taken out everything else that was a bit sugar beet-y
0:06:13 > 0:06:18and that water at the top is almost just sugar and water now.
0:06:20 > 0:06:23Next job - to reduce down the liquid into a thick syrup.
0:06:23 > 0:06:25Boiling's good for that.
0:06:26 > 0:06:27But as it thickens up,
0:06:27 > 0:06:30I risk it getting too hot and spoiling the sucrose...
0:06:30 > 0:06:36so I create a partial vacuum in the pan
0:06:36 > 0:06:38to boil it at a lower temperature.
0:06:38 > 0:06:42It's not difficult to make a syrupy solution,
0:06:42 > 0:06:47but to make actual real sugar crystals is quite hard.
0:06:54 > 0:06:59Now, it is a bit of a dark art, but...
0:06:59 > 0:07:00I think there's a chance
0:07:00 > 0:07:04that I might have got that concentrated enough now
0:07:04 > 0:07:07so that as it cools it could grow real sugar crystals.
0:07:07 > 0:07:13So I'm going to pour it off into here and leave it to do its stuff.
0:07:17 > 0:07:19Under a microscope,
0:07:19 > 0:07:22you can see sugar crystals appearing at the edge of the syrup.
0:07:22 > 0:07:26The longer you leave it, the bigger the crystals grow.
0:07:26 > 0:07:28I've decided it's best to come inside
0:07:28 > 0:07:32for the high-pressure finale of the sugar-refining process.
0:07:32 > 0:07:37What I've got in here is an incredibly sticky brown syrup
0:07:37 > 0:07:44and in it has grown a kind of multitude of tiny sugar crystals.
0:07:44 > 0:07:47What I need to do now is the almost impossible task
0:07:47 > 0:07:49of separating one from the other,
0:07:49 > 0:07:52and for that, I've built a centrifuge.
0:07:52 > 0:07:55Well, it's actually the old food processor,
0:07:55 > 0:07:56to which I've made something
0:07:56 > 0:07:59that's like a miniature washing machine drum.
0:08:02 > 0:08:04I'm going to put these on,
0:08:04 > 0:08:06because the accelerations necessary
0:08:06 > 0:08:09to separate sticky syrup from tiny sugar crystals
0:08:09 > 0:08:10are quite frightening.
0:08:10 > 0:08:12Right. One, two, three.
0:08:14 > 0:08:17Oh, you can see the syrup out there!
0:08:20 > 0:08:23The syrup's been flung straight out onto the sides of the bowl,
0:08:23 > 0:08:27hopefully leaving the crystals behind inside.
0:08:27 > 0:08:29Look!
0:08:29 > 0:08:31It's going white in there,
0:08:31 > 0:08:34you can see all the syrup coming out.
0:08:34 > 0:08:35And the stunning thing is,
0:08:35 > 0:08:39for all it started out as a dirty brown mass,
0:08:39 > 0:08:42the sugar that's left behind is almost pure white.
0:08:42 > 0:08:46Right, I'm going to take that apart. I mean, turn it down.
0:08:50 > 0:08:51Look at that!
0:08:53 > 0:08:57It's kind of...just white sugar.
0:08:58 > 0:09:00'That is my favourite bit of the process,
0:09:00 > 0:09:03'and they have a centrifuge just like mine at the refinery.'
0:09:03 > 0:09:04And this is it.
0:09:04 > 0:09:07'Only a whole lot bigger... and more powerful.'
0:09:09 > 0:09:13This uses kind of G-force just to fling out the brown syrup
0:09:13 > 0:09:17and leave behind the pure-white sugar crystals.
0:09:17 > 0:09:18And that really is.
0:09:18 > 0:09:21It's not bleached, it's not dyed, that's how sugar grows.
0:09:21 > 0:09:23Once you fling off the brown syrup that it grows in,
0:09:23 > 0:09:26it is left with these pure-white crystals.
0:09:26 > 0:09:28And if you want brown sugar,
0:09:28 > 0:09:31you can either crystallise it earlier on in the process,
0:09:31 > 0:09:34or you take the pure crystals
0:09:34 > 0:09:37and then they put on a tiny bit of the molasses that they've removed
0:09:37 > 0:09:39to get brown sugar.
0:09:39 > 0:09:41In other words,
0:09:41 > 0:09:46white sugar can actually be less processed than brown sugar.
0:09:46 > 0:09:50So is sucrose good or bad for you depending on where it comes from?
0:09:50 > 0:09:51No.
0:09:51 > 0:09:54Sucrose is sucrose, whether you find it in fruit,
0:09:54 > 0:09:56a sweet or a vegetable,
0:09:56 > 0:09:59and this factory is not making sucrose,
0:09:59 > 0:10:04it's extracting it from a vegetable that grows in a field down the road.
0:10:05 > 0:10:10But sucrose is not the only sugar that we find in our food.
0:10:10 > 0:10:13Fruit has lots of fructose and there's another,
0:10:13 > 0:10:16perhaps the most important sugar, glucose.
0:10:16 > 0:10:19The universal energy source for almost all life on Earth.
0:10:21 > 0:10:23That reaction right there
0:10:23 > 0:10:28shows you how much energy is available from just one jelly baby.
0:10:30 > 0:10:33And that holds the key to our next big question -
0:10:33 > 0:10:35why do we like sugar so much?
0:10:35 > 0:10:37Now, we need energy to function,
0:10:37 > 0:10:40for all of our cellular processes to work properly,
0:10:40 > 0:10:44and our cells get that energy from sugar.
0:10:45 > 0:10:49Without sugar, our cells couldn't do their jobs,
0:10:49 > 0:10:52our muscles wouldn't work, and most importantly,
0:10:52 > 0:10:54our brains simply wouldn't function.
0:10:54 > 0:10:57In fact, our brains are almost entirely dependent
0:10:57 > 0:10:58on glucose for energy.
0:11:00 > 0:11:02Glucose is so important to our brains
0:11:02 > 0:11:06that our taste for sugar is deeply rooted in our evolution.
0:11:06 > 0:11:10For our early ancestors, naturally-occurring sugar was rare.
0:11:10 > 0:11:13But, just like today's hunter-gatherers,
0:11:13 > 0:11:15they would go to great lengths to get hold of it.
0:11:17 > 0:11:21But our love of sugar might not just be down to the energy it provides.
0:11:22 > 0:11:26Researchers believe it can activate the release of endorphins
0:11:26 > 0:11:28and neurotransmitters like dopamine in the brain,
0:11:28 > 0:11:31that gives us a sense of exhilaration - a sugar rush.
0:11:31 > 0:11:35And that rush seems to go beyond simple pleasure -
0:11:35 > 0:11:40the mere taste of sugar might literally switch us on.
0:11:40 > 0:11:41So we can see how,
0:11:41 > 0:11:46Dr Tiina Eilola has asked me to take a classic test of mental agility.
0:11:46 > 0:11:49OK, this is it.
0:11:48 > 0:11:50Right.
0:11:50 > 0:11:52So, basically, what we're going to do
0:11:52 > 0:11:54is we're going to run a classic Stroop experiment.
0:11:56 > 0:11:58A Stroop experiment? OK.
0:11:58 > 0:12:00'I'll do this test twice,
0:12:00 > 0:12:03'each time swilling a different liquid round my mouth.
0:12:03 > 0:12:08'Once with glucose.' Excuse me. 'Once with a sweetener.' Here we go.
0:12:12 > 0:12:18'All I need to do is name the colour of the text, not read the word.'
0:12:17 > 0:12:22- Got that wrong.- And now you're going to have the second drink.
0:12:26 > 0:12:27Oops...
0:12:33 > 0:12:3698.33%.
0:12:36 > 0:12:38This is the end of the experiment.
0:12:38 > 0:12:40'With the test over,
0:12:40 > 0:12:44'Tiina reveals that the second drink had the glucose in it.'
0:12:44 > 0:12:47Crucially, I didn't drink either of them,
0:12:47 > 0:12:49I just tasted both.
0:12:49 > 0:12:53OK, so, how did I perform in test one, sweetener,
0:12:51 > 0:12:54- versus test two, glucose?- OK.
0:12:54 > 0:12:59So, what I can see from your reactions, you were overall faster
0:12:59 > 0:13:01when you had the sugar drink
0:13:01 > 0:13:04- than when you got the sweetened drink.- OK.
0:13:05 > 0:13:08So I performed better when I tasted glucose
0:13:08 > 0:13:11than when I tasted artificial sweetener.
0:13:10 > 0:13:12- That's right. - That's really interesting, right,
0:13:14 > 0:13:16because obviously it's not about energy release,
0:13:16 > 0:13:18it's about something else.
0:13:16 > 0:13:18Well, in this particular task,
0:13:18 > 0:13:19what it's really testing
0:13:19 > 0:13:22is your ability to ignore irrelevant information,
0:13:22 > 0:13:26in favour of the information that is relevant for a particular task.
0:13:29 > 0:13:30This shows that glucose
0:13:30 > 0:13:33triggers a direct link from the tongue to the brain
0:13:33 > 0:13:36and seems to boost our mood and our brain power,
0:13:36 > 0:13:39and that's what keeps us coming back for more.
0:13:39 > 0:13:42So essentially this is all about survival.
0:13:42 > 0:13:45It's almost like doubly, triply making sure
0:13:45 > 0:13:47that we will always eat sugar,
0:13:47 > 0:13:50and never forgetting how sugar is so important for us.
0:13:55 > 0:13:57That pleasure effect in our brain is so strong
0:13:57 > 0:13:59that some researchers believe
0:13:59 > 0:14:02that people really can become addicted to sugar,
0:14:02 > 0:14:03just like drink and drugs.
0:14:03 > 0:14:06In fact, there have been calls for sugar to be controlled,
0:14:06 > 0:14:09like we control alcohol and tobacco.
0:14:08 > 0:14:11So, still to come, I'll be meeting the doctor
0:14:11 > 0:14:13whose health depends on cutting out calories.
0:14:15 > 0:14:19Suddenly this wake-up call, actually I need to change, you know,
0:14:19 > 0:14:21my lifestyle, because this will only get worse.
0:14:19 > 0:14:24And I discover how it's being used as a secret weapon against disease.
0:14:24 > 0:14:28It's a neat, simple idea that addresses a massive problem.
0:14:29 > 0:14:32And Liz is on the case of artificial sweeteners.
0:14:32 > 0:14:36But first, just how bad is sugar's health reputation?
0:14:38 > 0:14:41I think there's more negatives towards sugar,
0:14:41 > 0:14:43on the news and TV programmes.
0:14:43 > 0:14:46No, I think it's definitely more negative than positive.
0:14:46 > 0:14:49Decays the teeth, I know that. I've still got my own teeth.
0:14:49 > 0:14:51If you're eating more sugar,
0:14:51 > 0:14:54obviously you're going to have more calories,
0:14:54 > 0:14:56so it means you're going to put on weight.
0:14:56 > 0:14:59Is sugar really such a health hazard?
0:14:59 > 0:15:03Well, when Scott Nelson fell ill, it was certainly a suspect.
0:15:04 > 0:15:10Scott is a doctor at the maternity unit at Glasgow Royal Infirmary,
0:15:10 > 0:15:11where chocolate is never far away.
0:15:13 > 0:15:15People are always very grateful for having babies.
0:15:15 > 0:15:18Quite often they bring chocolates as a gift and so on,
0:15:18 > 0:15:20so if you're in the labour ward in the middle of the night,
0:15:20 > 0:15:23there's normally coffee and chocolates hand-in-hand,
0:15:23 > 0:15:26and that's just part of what we're accustomed to.
0:15:24 > 0:15:29'A couple of years ago he started to feel unwell.'
0:15:31 > 0:15:35I wasn't feeling that great, I was tired all the time, I thought,
0:15:35 > 0:15:38"What's going on." I thought, "Let's do some blood tests."
0:15:38 > 0:15:41It was my liver function tests that were abnormal.
0:15:39 > 0:15:41Scott had fatty liver disease,
0:15:41 > 0:15:47a problem normally associated with obesity and alcohol abuse.
0:15:49 > 0:15:51I guess it was quite striking, because I don't drink,
0:15:51 > 0:15:52and suddenly - what was going on?
0:15:51 > 0:15:55So when you got that diagnosis that you'd got fatty liver disease,
0:15:55 > 0:15:57how did you feel?
0:15:58 > 0:16:02I think I was pretty shocked. I thought I was essentially healthy
0:16:02 > 0:16:03and then suddenly here I was
0:16:03 > 0:16:05having completely abnormal liver function tests.
0:16:05 > 0:16:08Caused a huge amount of abuse from my colleagues,
0:16:08 > 0:16:10who suddenly thought, here's this person who never drinks,
0:16:10 > 0:16:13has never drunk, and suddenly he's got abnormal liver function test.
0:16:12 > 0:16:16So Scott went to see a specialist, Professor Naveed Sattar.
0:16:16 > 0:16:20He told Scott that when you eat more calories than you burn off,
0:16:20 > 0:16:23one of the places fat can build up
0:16:23 > 0:16:25is your liver.
0:16:26 > 0:16:30The consequence of that is that the liver doesn't work as well,
0:16:30 > 0:16:34particularly in its ability to handle sugar metabolism.
0:16:32 > 0:16:37This can lead to other, more serious, health problems.
0:16:38 > 0:16:42The consequence for the individual is their sugar levels tend to rise
0:16:42 > 0:16:45and so liver fat is linked to a higher diabetes risk
0:16:45 > 0:16:47in many individuals.
0:16:48 > 0:16:52Also, in a small proportion, they'll have an increased likelihood
0:16:52 > 0:16:55of developing cirrhosis and potentially liver cancer.
0:16:55 > 0:16:56Suddenly, maybe, this wake-up call,
0:16:56 > 0:16:58actually, I need to change my lifestyle
0:16:58 > 0:17:03because this will only get worse if I don't do something dramatic.
0:17:03 > 0:17:06So, Scott cut down on the chocolates and canteen dinners,
0:17:06 > 0:17:08and took up cycling.
0:17:08 > 0:17:12How do you feel? Has it made a real difference to how you feel?
0:17:14 > 0:17:16There's no doubt that it makes a big difference.
0:17:16 > 0:17:18The whole, kind of,
0:17:18 > 0:17:20just doing exercise makes a difference.
0:17:20 > 0:17:23You know, I've got more energy, that's fantastic for the family.
0:17:23 > 0:17:26Being able to do things more, you're a lot less lethargic.
0:17:25 > 0:17:26Scott's not alone.
0:17:26 > 0:17:29It's thought one in five adults in the UK
0:17:29 > 0:17:32suffer from non-alcoholic fatty liver disease
0:17:32 > 0:17:34and it's on the increase.
0:17:34 > 0:17:36But sugar may not be entirely to blame.
0:17:38 > 0:17:41By and large, the average individual
0:17:41 > 0:17:44who has an over-consumption of calories, excess refined sugar,
0:17:44 > 0:17:47is part of that package of excess caloric intake.
0:17:46 > 0:17:49It's just calories, in any form, that are the problem.
0:17:49 > 0:17:52So is sugar the health hazard we think it is?
0:17:53 > 0:17:55If someone is healthy and does not have excess fat
0:17:55 > 0:17:58in the liver, of course they do not need to avoid sugar.
0:17:58 > 0:18:01The key thing with diet, of course, is to have a moderate intake
0:18:01 > 0:18:03as befits their lifestyle.
0:18:03 > 0:18:07Periods where they'll need excess sugar when they're exercising, periods when they will not.
0:18:08 > 0:18:11The truth is, sugar has no more calories than protein
0:18:11 > 0:18:13and has fewer than fat.
0:18:17 > 0:18:20Doctors do worry that the amount of sugar in processed foods
0:18:20 > 0:18:24makes it all too easy to eat more than our bodies can handle,
0:18:24 > 0:18:27because we don't always know when we're eating it.
0:18:27 > 0:18:30I'd like you to tell me how much sugar you think
0:18:30 > 0:18:33is in each of these drinks. You got a popular cola drink,
0:18:33 > 0:18:35a blackcurrant drink and a fruit juice, OK?
0:18:35 > 0:18:39So, you know, using these little sugar cubes as a visual aid,
0:18:39 > 0:18:43would you mind placing these bottles where you think they belong?
0:18:43 > 0:18:46I thought that, maybe, that could go there.
0:18:49 > 0:18:53- I think this has the most sugar in. - So place it where you think.
0:18:53 > 0:18:57I would say fruit juice the least.
0:18:57 > 0:19:01- Least in the cola? It's a real cola drink.- Oh, sorry.
0:18:59 > 0:19:01- We'll go here.- Not far behind.
0:19:05 > 0:19:07Well, I can now reveal,
0:19:07 > 0:19:11- that they actually all have the exact same amount of sugar.- Oh!
0:19:11 > 0:19:14- About 50 grams of sugar. - That surprising, yeah.
0:19:14 > 0:19:17The same amount of sugar. Around about 50 grams.
0:19:17 > 0:19:19- That's amazing.- Isn't it?
0:19:19 > 0:19:22I thought there'd be some sort of difference.
0:19:22 > 0:19:25What about the sugar in foods, then?
0:19:25 > 0:19:28I want you to tell me which of these three meals
0:19:28 > 0:19:30you think has the most sugar to the least sugar?
0:19:30 > 0:19:33You've got a popular burger.
0:19:33 > 0:19:35We've got a low-fat cheese and pasta bake
0:19:35 > 0:19:37and we've got tomato soup.
0:19:37 > 0:19:40I think that the bake might have the most.
0:19:40 > 0:19:41I think tomato soup.
0:19:41 > 0:19:44- I think the soup, actually, tomato. - Tomato soup?- Yeah.- Most sugar?
0:19:44 > 0:19:47- Probably the soup. - And what would be next?
0:19:47 > 0:19:49- The burger.- Yeah.
0:19:49 > 0:19:53- Soup, then burger, then pasta dish?- Yeah, agreed.
0:19:53 > 0:19:54OK, I can now reveal...
0:19:54 > 0:19:56- Are you excited?- Yeah.
0:19:56 > 0:19:58That the dish with the most sugar
0:19:58 > 0:20:01is actually the diet tomato and cheese pasta. OK?
0:20:02 > 0:20:04Then the soup, then the burger
0:20:04 > 0:20:08because many diet foods have lest fat.
0:20:08 > 0:20:10The flavour then is lacking, so what manufacturers do
0:20:10 > 0:20:13is they pump it full of sugar so it tastes better.
0:20:13 > 0:20:15- Interesting, isn't it?- It is.- Wow!
0:20:15 > 0:20:18Yeah, it can be quite surprisingly just how much sugar
0:20:18 > 0:20:20there is in everyday foods that we eat.
0:20:20 > 0:20:22But it all has to be listed on the label
0:20:22 > 0:20:25and the World Health Organisation recommends that we take
0:20:25 > 0:20:29on board no more than 10% of our calories from added sugar.
0:20:29 > 0:20:32You've probably all heard about high fructose corn syrup,
0:20:32 > 0:20:37a particular type of sugar syrup that's added to lots of food and drink in the US.
0:20:37 > 0:20:42There is some debate about whether such high levels of fructose could be bad for you
0:20:42 > 0:20:44because it overloads the liver and ultimately leads
0:20:44 > 0:20:47to greater fat deposition in the body, than other sugars.
0:20:47 > 0:20:51And, although, we don't use high fructose corn syrup in this country,
0:20:51 > 0:20:53we do add fructose to our food.
0:20:53 > 0:20:57So, it is an area of research that's well worth keeping an eye on.
0:20:57 > 0:21:00Now, some people are concerned that they do eat too much sugar
0:21:00 > 0:21:04and they've opted to use artificial sweeteners instead.
0:21:04 > 0:21:06But are artificial sweeteners a safe alternative?
0:21:08 > 0:21:11To find out, I'm going to make my own with chemicals in the lab.
0:21:15 > 0:21:18This is quite good fun, actually.
0:21:18 > 0:21:22OK, so cyclamic acid, hydrochloric acid, barium chloride,
0:21:22 > 0:21:24all in solution.
0:21:24 > 0:21:26They sound quite ominous as chemicals,
0:21:26 > 0:21:29but like all good chemical reactions, if you combine them
0:21:29 > 0:21:32in the right proportions, you get some interesting products.
0:21:34 > 0:21:38The last ingredient, though, is this stuff, sodium nitrite.
0:21:38 > 0:21:41Watch what happens when I combine the sodium nitrite
0:21:41 > 0:21:45with the rest of the chemicals. Here we go.
0:21:50 > 0:21:54There you have it, the precipitated salt
0:21:54 > 0:21:58of cyclamic acid, or sodium cyclamate,
0:21:58 > 0:22:01which is an artificial sweetener.
0:22:03 > 0:22:06Because of the risk of contamination I can't taste my sweetener,
0:22:06 > 0:22:10so time for more technical kit to see if it's the real thing.
0:22:16 > 0:22:18OK, now for the interesting bit.
0:22:18 > 0:22:21The sample's been analysed and, if I've got the chemistry right,
0:22:21 > 0:22:25there should be a peak appearing on this graph, around about here,
0:22:25 > 0:22:28indicating sodium cyclamate. Let's check it out.
0:22:30 > 0:22:34Bingo! There it is. I've made sodium cyclamate.
0:22:36 > 0:22:39Most of the sweeteners in our drink, in our food,
0:22:39 > 0:22:41are made in the lab, in a similar way.
0:22:41 > 0:22:44The most popular sweetener, aspartame,
0:22:44 > 0:22:47is made by synthesising two naturally occurring amino acids,
0:22:47 > 0:22:51joining them together to produce an entirely man-made substance.
0:22:52 > 0:22:55People are suspicious of artificial sweeteners
0:22:55 > 0:23:00because they're made in a lab, but are they doing us any harm?
0:23:00 > 0:23:03I asked an expert toxicologist if we should worry.
0:23:01 > 0:23:05The truth is, they have been extensively tested,
0:23:05 > 0:23:08both in animals and in humans
0:23:08 > 0:23:11and there's really no evidence
0:23:11 > 0:23:14that they cause any harm with the levels we're exposed to at all.
0:23:14 > 0:23:17Why would people think it's a good idea for a major food
0:23:17 > 0:23:22producing company to poison their consumers? That's not good business.
0:23:23 > 0:23:26Well, some people would argue the immediacy of a quick buck
0:23:26 > 0:23:31without doing the proper tests, but that's part of the reason, isn't it?
0:23:31 > 0:23:34If you're saying, categorically, there's nothing to worry about,
0:23:34 > 0:23:36why do people still worry?
0:23:36 > 0:23:38If I say "aspartame" to most people, they go,
0:23:38 > 0:23:40"Oh, yeah, it causes cancer, really bad for you."
0:23:39 > 0:23:45Aspartame has been through more studies than almost any additive in our diet.
0:23:45 > 0:23:49We have no evidence that, no matter how much of these sweeteners you consume,
0:23:49 > 0:23:51you would ever get cancer.
0:23:51 > 0:23:53- That's categorical? - That's categorical.
0:23:53 > 0:23:56There's no well-conducted study on the sweeteners
0:23:56 > 0:23:58we're using today causing cancer.
0:24:02 > 0:24:05So the evidence suggests artificial sweeteners don't do any harm.
0:24:05 > 0:24:09At least, not at the levels people consume them.
0:24:09 > 0:24:12There's more about artificial sweeteners on our website, bbc.co.uk/bang.
0:24:12 > 0:24:17Now, our final story on sugar has nothing to do with eating the stuff.
0:24:17 > 0:24:21it turns out it can be a real lifesaver when used in medicine.
0:24:21 > 0:24:24Medical uses for sugar, mainly in the form of honey,
0:24:24 > 0:24:27have been around for thousands of years.
0:24:27 > 0:24:30Papyrus scrolls, like these from ancient Egypt,
0:24:30 > 0:24:33are some of the earliest written medical records
0:24:33 > 0:24:36and it's absolutely fascinating when you go through them.
0:24:36 > 0:24:39You can see that honey is frequently mentioned as one of the key
0:24:39 > 0:24:41ingredients for treating wounds.
0:24:41 > 0:24:44Thousands of years later, modern clinical trials have shown
0:24:44 > 0:24:49that certain honeys do indeed have antibacterial properties.
0:24:49 > 0:24:55Medical grade honeys, like these, are routinely used in hospitals up and down the country.
0:24:55 > 0:24:58Treating infected wounds with sugar is one thing,
0:24:58 > 0:25:02but using sugar to prevent illness could be even better.
0:25:02 > 0:25:06Vaccines like these prevent lethal diseases of all kinds.
0:25:06 > 0:25:10They are one of the most effective health protection measures ever.
0:25:10 > 0:25:12But they can be difficult and costly to administer
0:25:12 > 0:25:15because it's vital that they're kept refrigerated
0:25:15 > 0:25:19from the moment when they're produced to the moment when they're injected into the patient.
0:25:20 > 0:25:24Shockingly, up to half of all vaccines have to be thrown away
0:25:24 > 0:25:27because when they warm up, the vaccine spoils.
0:25:27 > 0:25:32But a company in Leicester could be about to change all that with a little help from sugar.
0:25:32 > 0:25:34We know, that one of the real issues with vaccines is
0:25:34 > 0:25:38they have got to be transported under refrigeration. How can sugar help?
0:25:40 > 0:25:42Sugar is a well-known stabiliser.
0:25:42 > 0:25:46What we are essentially doing is we are mixing our vaccine
0:25:46 > 0:25:51with a sugar mixture and we dry that onto a membrane,
0:25:51 > 0:25:53a fibrous membrane.
0:25:53 > 0:25:58When the liquid dries, it changes into a sugar glass
0:25:58 > 0:26:01and once it's in a sugar glass format,
0:26:01 > 0:26:05the vaccine component that's trapped within the sugar,
0:26:05 > 0:26:09is completely protected from the external elements.
0:26:08 > 0:26:11The dried sugar keeps out any air or water
0:26:11 > 0:26:14and stops the vaccine from deteriorating.
0:26:14 > 0:26:17The dried pad is then packed into a plastic case.
0:26:17 > 0:26:20- So that doesn't need to be stored in the fridge?- That certainly does not.
0:26:22 > 0:26:26Once it's been manufactured, it can stay outside the fridge
0:26:26 > 0:26:29in the room temperature for a very long period.
0:26:27 > 0:26:31The unit can easily be connected to a standard syringe
0:26:31 > 0:26:33and when saline solution is flushed through it,
0:26:33 > 0:26:35the sugar instantly dissolves,
0:26:35 > 0:26:37releasing the vaccine into the needle.
0:26:39 > 0:26:42It's lightweight and you can pack large quantities
0:26:42 > 0:26:44into a backpack, for example,
0:26:44 > 0:26:47if you want to do a vaccination campaign
0:26:47 > 0:26:49in a remote, developing country.
0:26:48 > 0:26:50So this could make a huge difference, couldn't it?
0:26:52 > 0:26:56It certainly will. It offers you the stabilisation properties.
0:26:56 > 0:26:59It's easy to deliver, manufacture
0:26:59 > 0:27:03and also administer in large vaccination programmes.
0:27:02 > 0:27:06This technology also cuts the cost of administering vaccines
0:27:06 > 0:27:10against killer diseases, like tetanus, diphtheria, TB and measles,
0:27:10 > 0:27:12which we all need to have.
0:27:12 > 0:27:15What I really love about this is, is that it's so elegant,
0:27:15 > 0:27:20it's a neat, simple idea that addresses a massive problem.
0:27:20 > 0:27:22It's all about thinking differently
0:27:22 > 0:27:27and, by thinking differently, potentially saving millions of lives.
0:27:30 > 0:27:34Well, it appears as though a spoonful of sugar may well help the medicine go down.
0:27:34 > 0:27:35That's it for this week.
0:27:35 > 0:27:38We are back, same time, same channel next Monday.
0:27:39 > 0:27:43Visit bbc.co.uk/bang to watch my explosive investigation
0:27:43 > 0:27:46into sugar's energy and for even more on sugar,
0:27:46 > 0:27:49including hyperactive kids and honeycombs,
0:27:49 > 0:27:51follow the links to The Open University.
0:27:51 > 0:27:53- Thanks for watching. - Night.- Good night.
0:27:53 > 0:27:56Next week on Bang Goes The Theory...
0:27:56 > 0:27:59How safe are young people?
0:27:59 > 0:28:03Jem puts car safety seats to the test.
0:28:04 > 0:28:07I'm heading for a solid steel bar.
0:28:07 > 0:28:08How bad can it be?
0:28:07 > 0:28:11Liz discovers why traffic looks very different to children.
0:28:13 > 0:28:17Some of the children needed a speed difference of 20 miles an hour
0:28:17 > 0:28:19to notice one car is going faster than the other.
0:28:18 > 0:28:22And I find out how much we should worry about sudden cardiac arrest.
0:28:22 > 0:28:26There is something extraordinary about looking at your own heart
0:28:26 > 0:28:30on one of these because this isn't something I've ever done before.
0:28:45 > 0:28:48Subtitles by Red Bee Media Ltd