0:00:02 > 0:00:04There's one thing we can't argue with
0:00:04 > 0:00:06when it comes to our shopping.
0:00:07 > 0:00:10We Brits love our food.
0:00:12 > 0:00:16In fact, every year we get through an astonishing amount of it.
0:00:18 > 0:00:21We drink 60 billion cups of tea.
0:00:21 > 0:00:24That's enough to fill the Royal Albert Hall over 150 times.
0:00:28 > 0:00:32Every year, we eat over four billion loaves of bread.
0:00:32 > 0:00:35That's enough to fill Glasgow's Clyde Auditorium
0:00:35 > 0:00:37more than 300 times.
0:00:38 > 0:00:44We bought 185,000 tonnes of pasta.
0:00:44 > 0:00:47That's enough to fill Leeds Town Hall twice over.
0:00:50 > 0:00:53We're used to hearing all the bad news about the food we eat
0:00:53 > 0:00:55but I'd like to know the good news.
0:00:57 > 0:01:01I'm Cherry Healey and I want to know more about the food we buy,
0:01:01 > 0:01:04the supermarket staples that we put in our shopping trolleys
0:01:04 > 0:01:06every single week.
0:01:08 > 0:01:10I'm keen to see if science can help us
0:01:10 > 0:01:12unlock the secrets of our favourite foods.
0:01:14 > 0:01:17So in this programme, I'm delving deep into our trolley
0:01:17 > 0:01:20of supermarket staples to find out
0:01:20 > 0:01:24whether our favourite foods can also keep us healthy.
0:01:25 > 0:01:28And to do that, I need some help,
0:01:28 > 0:01:32and who better to ask than the good people of Britain?
0:01:32 > 0:01:35Across the country, our volunteers are raring to go.
0:01:37 > 0:01:40I hang out with some Cardiff cheese fanatics to see
0:01:40 > 0:01:42if cheese holds the secret to a healthy smile.
0:01:44 > 0:01:46- Look at that!- Oh, wow!
0:01:46 > 0:01:47It hasn't even dropped...
0:01:47 > 0:01:50I join the Loughborough hockey squad
0:01:50 > 0:01:54to find out if my morning coffee can turn me into a sporting champion.
0:01:54 > 0:01:56Getting sweaty!
0:01:56 > 0:01:58And I'm with A level students in Reading,
0:01:58 > 0:02:03to discover the magic food that could get all of us concentrating.
0:02:03 > 0:02:05That's a massive difference!
0:02:07 > 0:02:11It's time to test Britain's Favourite Supermarket Foods!
0:02:11 > 0:02:12CHEERING
0:02:19 > 0:02:24First up, it's a supermarket favourite we are crazy about.
0:02:24 > 0:02:26It's the world's most popular hot drink.
0:02:27 > 0:02:32The average supermarket sells more than 100 different varieties
0:02:32 > 0:02:36and here in Britain we drink 70 million cups of it a day.
0:02:38 > 0:02:42What could it be but a good old cup of coffee?
0:02:47 > 0:02:50If you're anything like me, the day hasn't properly started
0:02:50 > 0:02:52until you've had your first cup.
0:02:52 > 0:02:56But what is it about my morning coffee that perks me up
0:02:56 > 0:02:58and is it doing me any good?
0:03:00 > 0:03:03To find out, I'm on the streets of Bristol.
0:03:03 > 0:03:07Here in the South West, they buy more supermarket coffee
0:03:07 > 0:03:08than anywhere else in Britain.
0:03:10 > 0:03:11How often do you drink coffee?
0:03:11 > 0:03:13- Two times a day.- Three times a day.
0:03:13 > 0:03:15- Every other hour.- Wow!
0:03:15 > 0:03:18Why do you drink it?
0:03:18 > 0:03:19It gives me a bit of a lift.
0:03:19 > 0:03:21Why do you drink it?
0:03:21 > 0:03:23To keep me awake...for college.
0:03:23 > 0:03:25Is Otto allowed any coffee?
0:03:25 > 0:03:27No, not at all.
0:03:27 > 0:03:29Otto is hyper enough, thank you very much.
0:03:29 > 0:03:32How does it make you feel when you have a coffee?
0:03:32 > 0:03:34Like I can take on the world!
0:03:35 > 0:03:37It seems our dedicated followers of coffee
0:03:37 > 0:03:40are passionate about their daily brew.
0:03:40 > 0:03:41Beautiful.
0:03:41 > 0:03:43But what is it that gets them going?
0:03:43 > 0:03:47- What is in coffee that gives you that boost?- Caffeine, isn't it?
0:03:47 > 0:03:49Do you know how caffeine works?
0:03:49 > 0:03:51Not really.
0:03:51 > 0:03:53I think it's healthy, isn't it?
0:03:53 > 0:03:58No-one seems entirely sure how caffeine actually works.
0:03:58 > 0:04:01I want to know the science behind that coffee kick,
0:04:01 > 0:04:05so I've invited dietician and coffee guru Dr Sarah Schenker
0:04:05 > 0:04:08to help me filter the facts from the fiction.
0:04:10 > 0:04:12So, Sarah, like so many people,
0:04:12 > 0:04:15I love my cup of coffee in the morning,
0:04:15 > 0:04:17but how does caffeine give me that boost?
0:04:17 > 0:04:19What's going on in my brain?
0:04:19 > 0:04:21Well, it's just a mild stimulant
0:04:21 > 0:04:24so it puts you into your flight or fight mode,
0:04:24 > 0:04:25so you're ready for action.
0:04:25 > 0:04:28There seems to be quite a lot of confusion
0:04:28 > 0:04:30over whether caffeine is good for us or not.
0:04:30 > 0:04:34One of the things I've always believed is that it's really dehydrating.
0:04:34 > 0:04:38That's a really popular myth and one that a lot of people get wrong.
0:04:38 > 0:04:43Caffeine or coffee doesn't produce a net loss of water from the body.
0:04:43 > 0:04:47So when you drink it, you don't pee out more than you've just taken in.
0:04:47 > 0:04:49Can anyone drink as much caffeine as they like?
0:04:49 > 0:04:53If you're drinking a lot of caffeine, you know, one cup after another,
0:04:53 > 0:04:54one cup of coffee after another,
0:04:54 > 0:04:58you're not giving your body a chance for the caffeine to wear off,
0:04:58 > 0:05:01then you can put yourself into an agitated state.
0:05:01 > 0:05:05There's no official guidance on it but probably between
0:05:05 > 0:05:08about anything from one to maybe four or five cups of coffee
0:05:08 > 0:05:13throughout the space of the day, would be considered absolutely fine.
0:05:13 > 0:05:17But generally it's safe, and as long as I drink it in moderation,
0:05:17 > 0:05:18it's a great boost.
0:05:18 > 0:05:22Which is great to hear cos it's a good friend of mine in the morning.
0:05:23 > 0:05:27Caffeine is a natural stimulant that lots of us use as a pick-me-up,
0:05:27 > 0:05:29so it's good to know that it's safe.
0:05:30 > 0:05:33But there's one group of people who have a very special use
0:05:33 > 0:05:37for that caffeine hit -
0:05:37 > 0:05:38elite athletes.
0:05:40 > 0:05:44I've come to meet the Loughborough University men's hockey team,
0:05:44 > 0:05:47one of the top clubs in the country.
0:05:47 > 0:05:50So who here uses caffeine before they do sport?
0:05:50 > 0:05:52I use it just before games, generally.
0:05:52 > 0:05:55I feel like it gives me an edge during the matches.
0:05:55 > 0:05:57Whether it actually does or not, I'm not sure.
0:05:57 > 0:05:59Other people I'd heard were using it
0:05:59 > 0:06:01and I didn't want them to get a jump on me.
0:06:07 > 0:06:09She shoots, she scores! Check it out!
0:06:11 > 0:06:14But hockey is just as exhausting as I remember from school.
0:06:14 > 0:06:18It's no wonder the boys want to try and get a boost.
0:06:18 > 0:06:21Now I'm no athlete but I want to know if caffeine can do for me,
0:06:21 > 0:06:23what it's doing for these guys.
0:06:24 > 0:06:25To find out,
0:06:25 > 0:06:29I've arranged to meet sports scientist Professor Mike Gleeson.
0:06:30 > 0:06:34He studies the effects of caffeine on athletic performance
0:06:34 > 0:06:38so if anyone can help turn me into Jessica Ennis then it's him.
0:06:40 > 0:06:43So I've been speaking to the guys and they tell me
0:06:43 > 0:06:46that they use caffeine as a way to enhance their performance.
0:06:46 > 0:06:47How does it work?
0:06:47 > 0:06:50Well, it has been tested scientifically and the studies show
0:06:50 > 0:06:53that if you take enough caffeine at the right time,
0:06:53 > 0:06:55then it will improve exercise performance.
0:06:55 > 0:07:00So the boys consume their caffeine in either a pill or a liquid form
0:07:00 > 0:07:03via energy drinks, but what about a regular cup of coffee?
0:07:03 > 0:07:06Can I get the same effects from that?
0:07:06 > 0:07:08If you drink enough of the coffee.
0:07:08 > 0:07:11That usually probably means two strong cups of coffee to get
0:07:11 > 0:07:14the equivalent dose that these guys will be having.
0:07:14 > 0:07:15How can we test for that?
0:07:15 > 0:07:18Is there a way I can see whether it really, really works?
0:07:18 > 0:07:22Yeah. If you come along to the lab tomorrow, with your kit,
0:07:22 > 0:07:24then we can find out did it work for you?
0:07:26 > 0:07:31The next day I'm off to the lab to test the power of the cuppa.
0:07:31 > 0:07:34And I've even roped in Callum from the hockey squad to join me.
0:07:36 > 0:07:40Can the humble cup of coffee really give us more get-up-and-go?
0:07:40 > 0:07:42So, Callum and I want to know,
0:07:42 > 0:07:45does caffeine enhance your physical performance?
0:07:45 > 0:07:46How are we going to test that?
0:07:46 > 0:07:50Well, you're actually going to do that by running on a treadmill,
0:07:50 > 0:07:51to exhaustion.
0:07:51 > 0:07:53When you say exhaustion, what do you mean?
0:07:53 > 0:07:55Like lying on the floor, being sick?
0:07:55 > 0:07:57Well, it will feel hard
0:07:57 > 0:08:00and obviously it'll feel harder the longer you go for.
0:08:00 > 0:08:03You won't be able to carry on at the speed we're setting it at.
0:08:03 > 0:08:07OK, so it's at the point where at that speed and that incline,
0:08:07 > 0:08:10I cannot run any more.
0:08:10 > 0:08:12Exactly. So one of you will be on decaf,
0:08:12 > 0:08:14the other one will be on original coffee.
0:08:14 > 0:08:17You won't know which it is, we're not going to tell you.
0:08:17 > 0:08:20You'll do the test today and then we'll have you back next week
0:08:20 > 0:08:22and we'll reverse the treatments.
0:08:22 > 0:08:23Then we'll really see
0:08:23 > 0:08:26whether or not coffee actually does improve your performance.
0:08:26 > 0:08:29Callum and I gulp down our coffees
0:08:29 > 0:08:31but we don't know who's drinking decaf
0:08:31 > 0:08:35and who is on full strength caffeine.
0:08:35 > 0:08:38An hour later, it's time to take the plunge
0:08:38 > 0:08:41and start our test to exhaustion.
0:08:41 > 0:08:43MUSIC: "Theme From Rocky" by Bill Conti
0:08:51 > 0:08:53Mike's team have set up the treadmill at a speed
0:08:53 > 0:08:56and incline to match our fitness levels.
0:09:02 > 0:09:03It's getting sweaty.
0:09:06 > 0:09:08They know that at a certain point,
0:09:08 > 0:09:11we will literally be unable to run another step.
0:09:19 > 0:09:21The things I do for the sake of science!
0:09:26 > 0:09:29- Great job, well done. - Well done, brilliant, well done.
0:09:33 > 0:09:35I can't wait to find out how far I've run
0:09:35 > 0:09:39cos I've never run that hard, ever.
0:09:39 > 0:09:43And I can't believe I have to do this again next week.
0:09:47 > 0:09:49A week later, Callum and I are back at the lab
0:09:49 > 0:09:51to drink our mystery coffees
0:09:51 > 0:09:55and run ourselves into the ground all over again.
0:09:58 > 0:10:00Mike has reversed the coffees
0:10:00 > 0:10:05so that whoever was on the caffeine last week is now on decaf.
0:10:05 > 0:10:08We still don't know which is which but have kept our diets
0:10:08 > 0:10:10and routines exactly the same
0:10:10 > 0:10:13so, if there is any difference in performance,
0:10:13 > 0:10:15it can only be down to the coffee.
0:10:21 > 0:10:23That was really hard.
0:10:23 > 0:10:26That was tough. I could be totally wrong.
0:10:26 > 0:10:28Could be all in my mind, which is highly likely
0:10:28 > 0:10:33but it just did feel a little bit harder this week.
0:10:33 > 0:10:35I don't feel like I ran as far.
0:10:38 > 0:10:41Will the results prove the science
0:10:41 > 0:10:43behind the power of the caffeine kick?
0:10:46 > 0:10:48OK, Mike.
0:10:48 > 0:10:53I think that Callum and I have worked hard enough for an answer.
0:10:53 > 0:10:56So did the caffeine make a difference to our exercise?
0:10:57 > 0:11:00Ta-da!
0:11:00 > 0:11:04In the red is what you did on the caffeine, coffee.
0:11:04 > 0:11:06In the blue, the decaf.
0:11:06 > 0:11:09You both did a lot better.
0:11:09 > 0:11:13- Yes!- You did 30% longer.
0:11:13 > 0:11:15I felt like I did. Really.
0:11:15 > 0:11:17And you did about 10%.
0:11:17 > 0:11:19Right. Why the difference in the percent then?
0:11:19 > 0:11:22For somebody who's already athletic and well trained
0:11:22 > 0:11:26and maybe used to this kind of thing, it's not likely to make
0:11:26 > 0:11:29as big a difference as to somebody who's relatively naive to it.
0:11:29 > 0:11:32As someone who plays sport in a semi-professional way,
0:11:32 > 0:11:34that 10% must be quite important.
0:11:34 > 0:11:37Definitely, yeah. Now that I know that it makes that difference,
0:11:37 > 0:11:38it's worth taking it, like you say.
0:11:38 > 0:11:43I'm amazed that the coffee improved my performance by 30%.
0:11:43 > 0:11:47But scientists have had similar results in other studies
0:11:47 > 0:11:52and now think they know why caffeine can have such a dramatic effect.
0:11:53 > 0:11:55We get exhausted during exercise
0:11:55 > 0:12:00because a chemical message tells our brain and muscles we feel tired.
0:12:00 > 0:12:05Caffeine blocks this signal meaning we can keep going for longer.
0:12:12 > 0:12:15I've always thought that my morning cuppa gave me a boost.
0:12:15 > 0:12:18But now I know caffeine can also help my workout,
0:12:18 > 0:12:21I'm a committed coffee convert.
0:12:27 > 0:12:31From our favourite pick-me-up to our favourite indulgence.
0:12:31 > 0:12:36We Brits love a sugary treat but there's one sweet sensation
0:12:36 > 0:12:40we choose over every other and that's chocolate.
0:12:42 > 0:12:47On average, each one of us puts away over 22 pounds of the stuff
0:12:47 > 0:12:53every year but surely there are no healthy secrets to be found
0:12:53 > 0:12:56lurking in my favourite chocolate bar?
0:12:56 > 0:13:01Chocolate is my guilty pleasure. I just love it!
0:13:01 > 0:13:06It's so creamy and sweet and melts in your mouth.
0:13:06 > 0:13:10I just can't stay away from it, even though I know I probably should.
0:13:11 > 0:13:15Over the years, chocolate has had a pretty bad rap
0:13:15 > 0:13:18but is it really the devil incarnate?
0:13:18 > 0:13:21Recently, there have been all sorts of claims
0:13:21 > 0:13:25about chocolate's supposed health benefits.
0:13:25 > 0:13:28Could this be the light at the end of my chocoholic tunnel?
0:13:28 > 0:13:31To find the truth behind the headlines,
0:13:31 > 0:13:35I've invited dietician Sian Porter for a very chocolaty day out.
0:13:38 > 0:13:39Sian, you have to help me.
0:13:39 > 0:13:42I have a really passionate love affair with chocolate.
0:13:42 > 0:13:46But some people say it's good, some people say it's bad.
0:13:46 > 0:13:47What's going on?
0:13:47 > 0:13:50If you think about the raw ingredient, it's a cocoa pod
0:13:50 > 0:13:55and eventually it goes through processing and ends up as chocolate.
0:13:55 > 0:13:59But as part of the processing, quite often we're adding more fat,
0:13:59 > 0:14:02more sugar. So it is something that you are going to keep
0:14:02 > 0:14:06as an occasional treat and eat in small amounts.
0:14:06 > 0:14:09So the bean in and of itself isn't that bad
0:14:09 > 0:14:14but after we've processed it and added lots of sugar and fat,
0:14:14 > 0:14:17- it can be very high in calories. - Indeed.
0:14:17 > 0:14:20Why do people think that dark chocolate is better for you?
0:14:20 > 0:14:25Well, interestingly, if you look at the data from population studies,
0:14:25 > 0:14:29it would seem there is a link between intake of dark chocolate
0:14:29 > 0:14:31and reduced risk of certain disease.
0:14:31 > 0:14:35But we need more research to really tease out what's going on.
0:14:35 > 0:14:37So whilst you're saying there may be some health benefits,
0:14:37 > 0:14:41- you're not saying go and eat loads of chocolate?- Absolutely.
0:14:41 > 0:14:42Very disappointed, Sian.
0:14:44 > 0:14:47Is there something in my favourite food that could be causing
0:14:47 > 0:14:50these health benefits?
0:14:50 > 0:14:52To find out, I've come to Nottingham.
0:14:53 > 0:14:56Here at the university, Professor Ian MacDonald
0:14:56 > 0:15:00is going to show me just how chocolate can impact on my health.
0:15:02 > 0:15:06The science of chocolate. Now, that's my kind of studying.
0:15:06 > 0:15:09So, Ian, I've always thought of chocolate as something
0:15:09 > 0:15:13guilt-ridden and I should be really careful of.
0:15:13 > 0:15:15Is there anything you can tell me
0:15:15 > 0:15:17that will free me from chocoholic guilt?
0:15:17 > 0:15:20There is new research coming out that the cocoa flavonols
0:15:20 > 0:15:24that are in some chocolate may have beneficial effects,
0:15:24 > 0:15:28as far as promoting heart health and vascular function is concerned.
0:15:28 > 0:15:33Cocoa flavonols are natural chemicals found in cocoa beans.
0:15:33 > 0:15:35They protect the bean while it's growing
0:15:35 > 0:15:38and Ian thinks they may protect us as well.
0:15:41 > 0:15:44I want to see the science of the cocoa bean in action!
0:15:46 > 0:15:49So Ian and I have scoured the university and managed to find
0:15:49 > 0:15:53some volunteers willing to test the benefits of chocolate.
0:15:54 > 0:15:57- I'm Jo.- My name's Adam.- I'm Beth. - M name is Hon Jin.
0:15:57 > 0:16:00I love chocolate, much prefer dark chocolate.
0:16:00 > 0:16:03My favourite chocolate is white chocolate. It tastes so much better.
0:16:03 > 0:16:06I probably eat about ten bars of chocolate a week.
0:16:06 > 0:16:09I love chocolate. I would eat it every day if I could.
0:16:09 > 0:16:13Our intrepid chocolate chompers are off to Ian's lab.
0:16:13 > 0:16:17He's already tested their response to white chocolate
0:16:17 > 0:16:20which contains no flavonols at all
0:16:20 > 0:16:24but today we're taking them over to the dark side.
0:16:26 > 0:16:30If the theory is right, the cocoa flavonols in dark chocolate
0:16:30 > 0:16:34should have a noticeable impact on their cardiovascular systems.
0:16:34 > 0:16:37So, Ian, what's the plan?
0:16:37 > 0:16:39OK, so the plan is that first of all
0:16:39 > 0:16:41we need to get these four willing volunteers rested.
0:16:41 > 0:16:45So the first thing we have to do is just lie down and relax calmly.
0:16:45 > 0:16:49And then Liz will use the ultrasound machine to measure
0:16:49 > 0:16:52the effect of chocolate upon blood flow in the artery
0:16:52 > 0:16:54in the middle part of the arm.
0:16:54 > 0:16:59So, basically, they get to lie down, relax and be fed chocolate.
0:16:59 > 0:17:02That's correct. They lie down for three hours and behave themselves
0:17:02 > 0:17:05and we feed them chocolate in the middle of it.
0:17:05 > 0:17:07Tough life!
0:17:09 > 0:17:12The chocolate test requires total calm.
0:17:12 > 0:17:16Any excitement could cause a change in blood pressure
0:17:16 > 0:17:18that might throw the results.
0:17:18 > 0:17:21So the room is kept warm and dark
0:17:21 > 0:17:24and any potential distractions are removed.
0:17:26 > 0:17:29So now I need to leave the room while our volunteers
0:17:29 > 0:17:33are being tested because they need to stay completely relaxed.
0:17:33 > 0:17:36I don't know what they mean! I can do tranquil...
0:17:39 > 0:17:43The test is measuring the flexibility of the main artery
0:17:43 > 0:17:47in the arm because this is a prime indicator of a healthy heart.
0:17:48 > 0:17:52The more easily it expands in response to increased blood flow,
0:17:52 > 0:17:56the healthier the cardiovascular system.
0:17:56 > 0:17:58The importance of flexible arteries.
0:17:58 > 0:18:00Who knew?
0:18:04 > 0:18:08To test whether chocolate has any impact on this flexibility,
0:18:08 > 0:18:12Liz constricts blood flow to the arm with a cuff, so that she can
0:18:12 > 0:18:17measure how much the artery expands when the blood rushes back in.
0:18:19 > 0:18:22She does the test twice.
0:18:22 > 0:18:27First, to see the normal functioning of the artery,
0:18:27 > 0:18:33then again two hours after our volunteers have eaten 50 grams of dark chocolate.
0:18:35 > 0:18:38This is when the cocoa flavonols will have reached
0:18:38 > 0:18:40a peak in their bloodstream.
0:18:42 > 0:18:44Time for our results.
0:18:44 > 0:18:47Have the flavonols made their arteries more flexible?
0:18:48 > 0:18:52Has darkness triumphed over the light?
0:18:52 > 0:18:54So what have the tests told us?
0:18:54 > 0:18:59The tests have told us that all of the volunteers have responded
0:18:59 > 0:19:02positively to the dark chocolate,
0:19:02 > 0:19:07whereas actually the white chocolate did not have any effect whatsoever.
0:19:07 > 0:19:11You can see here that with the white chocolate it stays constant
0:19:11 > 0:19:14over the two hour period, whereas with the dark chocolate
0:19:14 > 0:19:17it goes up a bit and then a bit more. A substantial response.
0:19:17 > 0:19:21So the dark chocolate, in as short a space as two hours,
0:19:21 > 0:19:25has increased the flexibility of their arteries?
0:19:25 > 0:19:27- Yes, that's right. - That's quite amazing.
0:19:27 > 0:19:31Ian and other scientists have carried out similar experiments
0:19:31 > 0:19:33many times with the same results.
0:19:33 > 0:19:38In the short-term, the effects of dark chocolate only last a few hours,
0:19:38 > 0:19:42but studies suggest there may also be long-term benefits.
0:19:42 > 0:19:47At last, a reason to feel good about my obsession.
0:19:47 > 0:19:49So as a chocoholic,
0:19:49 > 0:19:53how can I incorporate these results into my everyday life?
0:19:53 > 0:19:57Well, if we can't persuade you to stop eating chocolate...
0:19:57 > 0:19:58You can't.
0:19:58 > 0:20:01If you replaced the milk chocolate that you ate by a dark chocolate
0:20:01 > 0:20:06that was rich in cocoa flavonols, it certainly wouldn't do any harm
0:20:06 > 0:20:10and it may be of benefit in terms of promoting a healthier heart.
0:20:10 > 0:20:13If you want to move over to the dark side,
0:20:13 > 0:20:17go for a chocolate that's 70% cocoa solid or above.
0:20:18 > 0:20:20The higher the percentage,
0:20:20 > 0:20:23the more likely it is to be rich in flavonols.
0:20:25 > 0:20:28Whilst chocolate may not be the healthiest snack,
0:20:28 > 0:20:32if you're a chocoholic like me, and you can't bear to be without it,
0:20:32 > 0:20:36why not swap your milk chocolate for a few pieces of dark.
0:20:36 > 0:20:38Your heart may thank you for it.
0:20:44 > 0:20:47Still to come, I find out whether a simple spice
0:20:47 > 0:20:50could stop cancer cells in their tracks?
0:20:50 > 0:20:53Seems really powerful stuff!
0:20:53 > 0:20:55It's pretty amazing.
0:20:55 > 0:20:58And these A level students test a brain-boosting berry
0:20:58 > 0:21:01that could help them fly through their exams.
0:21:01 > 0:21:05- That's a massive difference. - Quite a big difference, yeah.
0:21:10 > 0:21:14But first, it's one of our trusty reliables.
0:21:14 > 0:21:18There are some favourite foods we turn to time and time again.
0:21:20 > 0:21:23Kitchen essentials we keep in our cupboards
0:21:23 > 0:21:27and put into our shopping bags, almost without thinking.
0:21:28 > 0:21:30And if there's one British staple
0:21:30 > 0:21:35that's been a favourite for centuries, it's the humble spud.
0:21:35 > 0:21:38Whether they're mashed, boiled, baked or fried,
0:21:38 > 0:21:43potatoes are a national institution.
0:21:43 > 0:21:45Every year, each one of us
0:21:45 > 0:21:49chomps our way through 191 pounds,
0:21:49 > 0:21:52or 14 stones' worth of potatoes.
0:21:52 > 0:21:55That's a lot of spuds!
0:21:55 > 0:21:59But not everyone is in love with the spud.
0:21:59 > 0:22:01In fact, sales of potatoes have dropped 20%
0:22:01 > 0:22:06in the last ten years and are continuing to tumble.
0:22:08 > 0:22:10I'm in Scotland where they buy
0:22:10 > 0:22:12fewer potatoes than anywhere else in Britain.
0:22:12 > 0:22:17Perhaps if I butter up the good people of Glasgow,
0:22:17 > 0:22:20they'll tell me why we're spurning the spud.
0:22:22 > 0:22:25How do you ladies feel about the potato?
0:22:25 > 0:22:27- Pretty boring. - Pretty boring, yeah.
0:22:27 > 0:22:30I think they're too common.
0:22:30 > 0:22:32They don't look good.
0:22:32 > 0:22:35I do eat chips but I don't make them out of potato.
0:22:35 > 0:22:37- What do you make them out of? - I just get chips...
0:22:37 > 0:22:40Oh, obviously they're made out of potatoes. Oh!
0:22:44 > 0:22:45It's not an exciting colour.
0:22:45 > 0:22:47They look boring.
0:22:47 > 0:22:49It's not an amazingly exciting texture.
0:22:49 > 0:22:50Just bland.
0:22:50 > 0:22:51It's just a potato.
0:22:51 > 0:22:54Just a potato.
0:22:54 > 0:22:58We seem to think of the potato as the Volvo of the veggie world.
0:22:58 > 0:23:01Reliable, but essentially, a little bit dull,
0:23:01 > 0:23:04But does it deserve this dreary reputation
0:23:04 > 0:23:08or is there more to the simple spud than meets the eye?
0:23:08 > 0:23:12I think there could be hidden depths to our tasty tatties
0:23:12 > 0:23:17so I've come to the University Of Leeds food science laboratory
0:23:17 > 0:23:21where Dr Joanne Maycock puts potatoes through their paces.
0:23:21 > 0:23:24So, Dr Jo, I've been on the streets of Glasgow
0:23:24 > 0:23:29and people seem to think the potato is just a big, bulky, starchy carb
0:23:29 > 0:23:33that you have next to the fun stuff, next to the meat and veg
0:23:33 > 0:23:36but really it's not that exciting.
0:23:36 > 0:23:39In fact the potato is a really nutritious vegetable.
0:23:39 > 0:23:41So it's not just a brown doorstop?
0:23:41 > 0:23:44Oh, no. Far from it. It contains carbohydrates
0:23:44 > 0:23:47but it also contains protein, lots of minerals
0:23:47 > 0:23:52such as potassium, lots of vitamins such as vitamin B6, vitamin C.
0:23:52 > 0:23:54You say vitamin C.
0:23:54 > 0:23:59When I think vitamin C, I think oranges, you know, lots of fruits.
0:23:59 > 0:24:02I don't think...brown potato.
0:24:02 > 0:24:07Yeah, so the potato gives you half your recommended daily amount of vitamin C.
0:24:07 > 0:24:13Half? From a potato? You wouldn't know it to look at it.
0:24:13 > 0:24:17I can't believe that potatoes are chock full of vitamin C
0:24:17 > 0:24:21and have more potassium than bananas!
0:24:21 > 0:24:24But it turns out they have even more secrets to reveal,
0:24:24 > 0:24:27once we get under the skin...
0:24:27 > 0:24:29OK, so what we can do is we can use the microscope
0:24:29 > 0:24:31to look at what's inside a potato.
0:24:31 > 0:24:35I'm assuming more potato.
0:24:36 > 0:24:38These larger circles, these are the cell walls
0:24:38 > 0:24:41and this shows you the fibre that's in the potato.
0:24:41 > 0:24:44It seems to be mostly made up of those.
0:24:44 > 0:24:48So potato is really high fibre.
0:24:48 > 0:24:49Potato is high fibre.
0:24:49 > 0:24:52And then also here, this is the potato skin.
0:24:52 > 0:24:55But the cells are a lot more dense, they're smaller
0:24:55 > 0:24:56and there's a lot more of them.
0:24:56 > 0:24:59So does the skin have the highest amount of fibre in it?
0:24:59 > 0:25:02The skin does have the highest amount of fibre in it.
0:25:02 > 0:25:05So what you need to do is, when you have your jacket potato,
0:25:05 > 0:25:07- make sure that you always eat the skin.- Nice!
0:25:07 > 0:25:10It's the best bit as well! Cos it's crispy.
0:25:10 > 0:25:12It's the tastiest bit.
0:25:12 > 0:25:14Why do you need fibre?
0:25:14 > 0:25:16So fibre's good for you because it makes you feel full.
0:25:16 > 0:25:21It also has roles in helping reduce obesity, high blood pressure,
0:25:21 > 0:25:25heart disease. There's lots of reasons why we should be eating fibre.
0:25:25 > 0:25:29The magic of potatoes! It just never fails to astound me.
0:25:29 > 0:25:33A fibre rich diet keeps your whole intestinal system running smoothly
0:25:33 > 0:25:38and let's face it, who doesn't want a happy bowel?
0:25:38 > 0:25:42And scientists think it may also help to protect us from cancer
0:25:42 > 0:25:44and high cholesterol.
0:25:44 > 0:25:49But when I think of fibre, I think of bran or brown rice.
0:25:49 > 0:25:53I want to know if a potato can hold its own against something
0:25:53 > 0:25:56we think of as a real high fibre hitter.
0:25:56 > 0:25:59So Joanne has devised a fibre fight!
0:25:59 > 0:26:03MUSIC: "Eye Of The Tiger" by Survivor
0:26:03 > 0:26:06In one corner we have the health-food favourite,
0:26:06 > 0:26:08a bowl of brown rice.
0:26:08 > 0:26:12In the other corner, a lowly baked spud.
0:26:12 > 0:26:15We're going to measure the fibre content of each
0:26:15 > 0:26:18and find our champion.
0:26:18 > 0:26:20I think most people looking at these would say that the rice
0:26:20 > 0:26:22has the highest fibre content.
0:26:22 > 0:26:23OK, let's find out.
0:26:23 > 0:26:25OK, so we need to put our safety specs on.
0:26:25 > 0:26:28Serious, sciencey stuff beginning. OK.
0:26:30 > 0:26:32To find out which food is our fibre hero,
0:26:32 > 0:26:35Jo needs to separate out the fibre from everything else
0:26:35 > 0:26:39and it's trickier than it sounds!
0:26:40 > 0:26:45Firstly, our two contenders are dried out and ground down.
0:26:47 > 0:26:49- You cremated the potato? - That's right.
0:26:49 > 0:26:51So that is potato powder.
0:26:51 > 0:26:54So that's our potato and that's our rice.
0:26:54 > 0:27:00Next, Jo adds liquid enzymes which will reveal our precious fibre.
0:27:00 > 0:27:04Our bodies find it hard to digest fibre so most of it passes
0:27:04 > 0:27:08straight through us helping to keep us regular!
0:27:08 > 0:27:12And in the same way, the enzymes can't digest it either,
0:27:12 > 0:27:15so it gets left behind in the beaker.
0:27:15 > 0:27:18So you're going to add enzymes and they're going to eat away
0:27:18 > 0:27:21- all of the things that you don't want to measure.- That's right.
0:27:21 > 0:27:24So you'll just be left with the fibre. I actually understand that.
0:27:24 > 0:27:27Down in one? Dare me?
0:27:27 > 0:27:29Go on then!
0:27:34 > 0:27:37Finally, our beakers of fibre are filtered
0:27:37 > 0:27:40and dried out in the oven.
0:27:41 > 0:27:45It might not look like it but this is what's left of our potato
0:27:45 > 0:27:47and brown rice samples.
0:27:47 > 0:27:49This is the pure fibre content.
0:27:49 > 0:27:53So we're going to weigh them and find out who the winner is.
0:27:54 > 0:27:56Ta-da! Bon appetite!
0:27:58 > 0:28:01OK, so I've worked out the results.
0:28:01 > 0:28:04The rice has got 3.55% fibre
0:28:04 > 0:28:08and potato has got 5.44% fibre.
0:28:08 > 0:28:12So that's one and a half times greater amount than the rice.
0:28:12 > 0:28:16So the potato beats the brown rice hands down?
0:28:16 > 0:28:17Yes.
0:28:17 > 0:28:20I'm so surprised. The fact that it's that much more is amazing.
0:28:22 > 0:28:26It's a killer blow for the brown rice.
0:28:26 > 0:28:28We have our champion.
0:28:33 > 0:28:38So it turns out that the potato is a wonder food in disguise!
0:28:38 > 0:28:40Now that I know the truth,
0:28:40 > 0:28:43can I rescue this unsung hero of the veggie world?
0:28:43 > 0:28:48Can we, the people of Britain, fall back in love with the spud?
0:28:49 > 0:28:53Back in Glasgow I've devised a cunning plan
0:28:53 > 0:28:58to show people just how much of a healthy hero the potato really is.
0:29:00 > 0:29:04These plates of food all weigh exactly the same.
0:29:04 > 0:29:07One of these plates of food has more fibre than any of the others,
0:29:07 > 0:29:1150% of your daily recommended dose of vitamin C,
0:29:11 > 0:29:16more than 90% of your daily requirement of potassium
0:29:16 > 0:29:19- and less than one gram of fat. - Right.
0:29:19 > 0:29:22Which do you think it is?
0:29:22 > 0:29:26- I'd love it to be the chocolate cake! - Wouldn't we all, Lilly?
0:29:26 > 0:29:29- I think it's the carrots. - Broccoli?
0:29:29 > 0:29:31Broccoli?
0:29:31 > 0:29:34I think the potato, as long as you eat the jacket.
0:29:34 > 0:29:38I'm going to tell you that your wife is right.
0:29:38 > 0:29:42- Oh, dear. Oh, dear! - So you can listen to me in future.
0:29:42 > 0:29:46- You'll have to listen to her now. - Yes, dear. Yes, dear.
0:29:46 > 0:29:49We've all heard about supposed super foods
0:29:49 > 0:29:52making all sorts of nutritional claims and boasts.
0:29:52 > 0:29:56But it turns out we've had a genuine superhero
0:29:56 > 0:29:59sitting in our shopping trolley all along.
0:30:06 > 0:30:09Next up, I'm looking for the secret power
0:30:09 > 0:30:12in one of our all-time creamy favourites.
0:30:12 > 0:30:16Every year, 1.8 million British dairy cows
0:30:16 > 0:30:21work their udders off to produce the 13 billion litres of milk we use
0:30:21 > 0:30:27for everything from butter on our toast to the cream in our coffee,
0:30:27 > 0:30:32because Britain is a nation that is doolally about dairy.
0:30:32 > 0:30:36There's one dairy delight we just can't seem to get enough of.
0:30:36 > 0:30:41In fact, we eat a staggering 700,000 tonnes of it every year.
0:30:42 > 0:30:44It is, of course, cheese.
0:30:52 > 0:30:54There's no doubt we love our cheese
0:30:54 > 0:30:58but what are our top five absolute favourites?
0:30:58 > 0:31:03In fifth place it's everyone's stinky delight, blue Stilton.
0:31:03 > 0:31:06Fourth place goes to the Double Gloucester
0:31:06 > 0:31:08and third to the Red Leicester.
0:31:08 > 0:31:12The runner-up in second place is mozzarella -
0:31:12 > 0:31:13must be all those pizzas.
0:31:15 > 0:31:20But in first place it's the trusty cheddar. No surprise there.
0:31:20 > 0:31:23But did you know we actually eat six times more cheddar
0:31:23 > 0:31:25than any other cheese?
0:31:30 > 0:31:33But what is it that makes cheese so irresistible
0:31:33 > 0:31:38and does our dairy addiction do us more harm than good?
0:31:38 > 0:31:42To find out, I've come to Wales.
0:31:42 > 0:31:44Here at Cardiff's famous castle,
0:31:44 > 0:31:47they host the biggest British cheese festival.
0:31:47 > 0:31:51For one weekend only, thousands of fromage fanatics
0:31:51 > 0:31:54from across the globe have converged on this spot.
0:31:54 > 0:31:59And if anyone should know why we love cheese it's them!
0:32:01 > 0:32:03- It's the best thing in the world. - It improves any meal.
0:32:03 > 0:32:07Forget fast food. An apple and a lump of cheese. Job done.
0:32:07 > 0:32:12Clearly we love our cheeses but do they love us?
0:32:14 > 0:32:16What is it in cheese that people are worried about?
0:32:16 > 0:32:19They're worried about the fat.
0:32:19 > 0:32:22I would rather not think about that.
0:32:22 > 0:32:26- Calories?- Waistlines have something to do with it when you're our age.
0:32:26 > 0:32:28There's a lot of fat in it. And dairy.
0:32:28 > 0:32:32Is our delicious dairy actually a dieting disaster?
0:32:32 > 0:32:36Perhaps cheese-lover and dietician Sue Baic
0:32:36 > 0:32:39can WHEY in on this cheesy conundrum.
0:32:41 > 0:32:43Sue, are you a cheese fan?
0:32:43 > 0:32:45I'm a big cheese fan. It's a great food.
0:32:45 > 0:32:48It's full of protein and it's also full of calcium,
0:32:48 > 0:32:51which is necessary for strong bones and teeth.
0:32:51 > 0:32:54But people are worried about whether cheese is healthy or not.
0:32:54 > 0:32:56It's very high in fat.
0:32:56 > 0:32:59Yeah, well that's true. Cheese is about a third fat.
0:32:59 > 0:33:02And quite a large proportion of that is saturated animal fat,
0:33:02 > 0:33:05the one that puts our cholesterol levels up.
0:33:05 > 0:33:08But if you keep your portion sizes reasonably moderate, then it's not a problem.
0:33:08 > 0:33:13So something like around 50 grams or slightly bigger than that
0:33:13 > 0:33:17sort of sized matchbox, is what a portion size would be.
0:33:17 > 0:33:19That doesn't look very much.
0:33:19 > 0:33:24It's not huge but if you think about lots of tricks to make it go further.
0:33:24 > 0:33:27You can use a very mature cheese and because it's got a stronger flavour,
0:33:27 > 0:33:29you get away with using less.
0:33:29 > 0:33:32- Extra mature cheddar will go a lot further.- Or a stinky stilton? - A stinky stilton.
0:33:32 > 0:33:36- So you feel like you've really had some cheese but you haven't had too much.- Exactly.
0:33:36 > 0:33:40So it's packed full of goodness, but beware of portion control.
0:33:40 > 0:33:42Anything else we should know about cheese?
0:33:42 > 0:33:45Not only is cheese a good source of calcium for our bones and teeth,
0:33:45 > 0:33:48but there is some research that shows that cheese can help
0:33:48 > 0:33:50our dental health in other ways, actually.
0:33:50 > 0:33:55- So cheese can also help protect our teeth?- It can.- Amazing!
0:33:55 > 0:34:00Can a cheesy treat really help protect my pearly whites?
0:34:00 > 0:34:04To find the answer I've called in Professor Alastair Sloan
0:34:04 > 0:34:08from the Cardiff University Dental School for assistance.
0:34:08 > 0:34:11When it comes to teeth, he certainly knows the drill.
0:34:12 > 0:34:16So I'm intrigued to find out how cheese can help with dental health.
0:34:16 > 0:34:19To understand that, we need to understand what happens in the mouth
0:34:19 > 0:34:23when you eat foodstuffs that can cause erosion of your teeth.
0:34:23 > 0:34:27Everyday foodstuffs such as oranges and lemons and fruit juices,
0:34:27 > 0:34:30including our favourite cola drinks, sadly even wine,
0:34:30 > 0:34:33they contain dietary acids in quite high amounts
0:34:33 > 0:34:36and that can cause erosion of your dental enamel.
0:34:36 > 0:34:40So these cause erosion of our teeth.
0:34:40 > 0:34:42Not tomato sauce. No!
0:34:42 > 0:34:44Sadly even tomato sauce is quite acidic.
0:34:44 > 0:34:48I can see here that you have a penny and a glass of orange juice.
0:34:48 > 0:34:50Are you going to do the classic childhood experiment?
0:34:50 > 0:34:52Very simple experiment.
0:34:52 > 0:34:55A very grubby two pence coin, very dirty.
0:34:55 > 0:34:57Three days ago we dropped a very similar coin
0:34:57 > 0:35:00into this glass of everyday orange juice.
0:35:00 > 0:35:03- And if you look carefully, what you can see...- Shiny!
0:35:03 > 0:35:05- Very shiny. - Good for the penny...
0:35:05 > 0:35:08Great for the penny. But imagine if that was your actual tooth.
0:35:08 > 0:35:10The acids there have cleaned the penny
0:35:10 > 0:35:12and they do the same thing to your tooth enamel.
0:35:12 > 0:35:15And that enamel softens.
0:35:15 > 0:35:19- And erodes.- And erodes.- So how does cheese prevent the erosion?
0:35:19 > 0:35:22Cheese stimulates the body's natural defence mechanism in the mouth
0:35:22 > 0:35:24and that's the production of saliva.
0:35:25 > 0:35:30To test Alastair's theory, we need a volunteer who likes cheese.
0:35:30 > 0:35:33Where on earth will we find one of those?
0:35:33 > 0:35:35She looks really smiley.
0:35:37 > 0:35:39Excuse me. I'm assuming you quite like cheese.
0:35:39 > 0:35:41I do, I'm Lady Cheddar.
0:35:41 > 0:35:45- How would you feel about joining me for a cheesy experiment? - I'm up for that.
0:35:45 > 0:35:48With the help of our lovely cheesemonger,
0:35:48 > 0:35:52Alastair is going to test whether a piece of cheese
0:35:52 > 0:35:55can protect our teeth from the ravages of acidic food.
0:35:56 > 0:35:58First he needs to get a normal reading
0:35:58 > 0:36:01of the state of Susan's mouth.
0:36:01 > 0:36:03If you don't mind spitting into this tube for me.
0:36:03 > 0:36:05- I need lots of spit. - Lots of spit.
0:36:05 > 0:36:08And then we can make sure the pH of your mouth is normal.
0:36:08 > 0:36:10Is normal. OK.
0:36:10 > 0:36:13- SHE LAUGHS - I know. Don't look. Don't look.
0:36:13 > 0:36:17A pH scale measures the acidity of a substance, a food,
0:36:17 > 0:36:20or in our case, Susan's spit.
0:36:21 > 0:36:26- This machine tells us what the pH of Susan's mouth is.- Absolutely does.
0:36:26 > 0:36:29And a figure that's around seven means your mouth is at neutral pH.
0:36:29 > 0:36:31It's very normal.
0:36:31 > 0:36:36Numbers below seven means your mouth is more acid like.
0:36:36 > 0:36:39And at 5.5 and below, enamel will start to dissolve.
0:36:39 > 0:36:44The orange juice should have an instant impact on Susan's mouth.
0:36:46 > 0:36:49- Spit for me again, please. A nice, big, healthy sample.- So much spit!
0:36:49 > 0:36:51Loads of spit.
0:36:51 > 0:36:55OK. Let's take a look and see what we've got on this sample here.
0:36:55 > 0:36:58The probe goes in. Wow!
0:36:58 > 0:37:04- Wow!- So we are now down to 4.75 which is below that critical 5.5 pH.
0:37:04 > 0:37:07Just from that much orange juice.
0:37:07 > 0:37:09Just from two big mouthfuls of orange juice.
0:37:09 > 0:37:13As long as Susan's mouth remains acidic from the orange juice,
0:37:13 > 0:37:19her teeth will be under attack so Alastair continues to test her spit.
0:37:21 > 0:37:23Surely she's going to run out!
0:37:24 > 0:37:29- We can't watch. It doesn't help. - She'll get spit shame.
0:37:29 > 0:37:34It takes almost 20 minutes for Susan's mouth to return to its normal pH level.
0:37:34 > 0:37:37So what has all that spitting told us?
0:37:37 > 0:37:41- Well, first of all it's told us that Sue is very normal.- Yay!
0:37:41 > 0:37:44And that actually what's happening in her mouth is she drank
0:37:44 > 0:37:48the orange juice and her teeth were under attack from the acid.
0:37:48 > 0:37:51Once Susan's mouth has returned to neutral,
0:37:51 > 0:37:53it's time to run the test again.
0:37:54 > 0:37:58But this time we're bringing in the big guns
0:37:58 > 0:38:02in the form of a small piece of cheddar.
0:38:02 > 0:38:05Can cheese really save Susan from an acid attack?
0:38:07 > 0:38:11So, the cheese round! So what does Susan do now?
0:38:11 > 0:38:14We need to have some orange juice, as we were.
0:38:14 > 0:38:16And as soon as you've drunk that,
0:38:16 > 0:38:19we need you to eat the cheese straightaway.
0:38:19 > 0:38:21This is the nice bit of the test, yeah?
0:38:21 > 0:38:23I feel like a mouse now.
0:38:23 > 0:38:25What we hope to see is that the pH
0:38:25 > 0:38:28should be above that critical pH of 5.5.
0:38:28 > 0:38:31- But the proof will be in the spit. - Will be in the spitting.
0:38:33 > 0:38:37- OK. I'll look away.- Little bit more.
0:38:37 > 0:38:39You and your spit! You love it.
0:38:39 > 0:38:42I'm just going to keep my eye on the dial.
0:38:42 > 0:38:44- Well, look at that. - Oh, wow!
0:38:44 > 0:38:48- That is amazing, isn't it? - Hasn't even dropped.
0:38:48 > 0:38:52So before, it took nearly 20 minutes for Susan's mouth
0:38:52 > 0:38:55to reach a neutral point and it's now taken...
0:38:55 > 0:38:57- Less than a minute. - Immediately, almost.
0:38:57 > 0:39:00Pretty much an immediate response.
0:39:00 > 0:39:02So eating a piece of cheese can really help to bring
0:39:02 > 0:39:06- your mouth back to neutral pH, which stops acid erosion.- Absolutely.
0:39:06 > 0:39:08So what's going on?
0:39:08 > 0:39:12How does the cheese counteract the acid in our mouths so quickly?
0:39:14 > 0:39:18Firstly, the chewiness and flavour of cheese make it one
0:39:18 > 0:39:21of the best foods there is for stimulating saliva.
0:39:21 > 0:39:26And saliva is the body's own defence system, neutralising the mouth against acid.
0:39:26 > 0:39:32But the calcium in cheese may also work directly on teeth,
0:39:32 > 0:39:37replacing minerals and repairing some of the damage of erosion.
0:39:37 > 0:39:39In theory then, after you've had a meal,
0:39:39 > 0:39:42it's better to have a piece of cheese say than brush your teeth?
0:39:42 > 0:39:45You should never brush your teeth immediately after eating.
0:39:45 > 0:39:47You saw with Sue and the orange juice alone,
0:39:47 > 0:39:50it took 20 minutes to recover back to neutral.
0:39:50 > 0:39:53So if you brush your teeth inside that 20 minute period,
0:39:53 > 0:39:56what you're doing is brushing acid around your teeth.
0:39:56 > 0:39:59You must always wait at least 20 minutes before brushing
0:39:59 > 0:40:01your teeth after eating.
0:40:01 > 0:40:05Or, as we can see, a small piece of cheese may improve that process.
0:40:05 > 0:40:10Did you have any idea, Susan, that your beloved cheese had so many wonderful properties?
0:40:10 > 0:40:13No, I didn't. No, that is absolutely brilliant.
0:40:13 > 0:40:17- It's not just a lovely way to end a meal but it's practical too. - Absolutely.- I love it.
0:40:17 > 0:40:18It's fab.
0:40:23 > 0:40:25Who would have thought something so delicious
0:40:25 > 0:40:28could help protect my precious pearly whites?
0:40:30 > 0:40:34As a nation, our favourite foods are changing
0:40:34 > 0:40:37as we become ever braver in our eating habits.
0:40:37 > 0:40:40Our supermarkets are now full of aisles
0:40:40 > 0:40:44devoted to exotic foods and spices.
0:40:44 > 0:40:47But our absolute favourite spicy dish is curry.
0:40:49 > 0:40:54In fact, it's estimated that we spend an astonishing £4 billion on it every year.
0:40:55 > 0:40:57I love a curry.
0:40:57 > 0:41:00But I've always thought they were bad for you.
0:41:00 > 0:41:04Could my Friday night favourite have any health benefits?
0:41:04 > 0:41:08I want to know what's in a curry and is it any good for me?
0:41:10 > 0:41:13I've come to Leicester in the heart of the Midlands.
0:41:15 > 0:41:17This is Britain's curry central,
0:41:17 > 0:41:22where there are more curry houses than anywhere else in the country.
0:41:22 > 0:41:25Where better to discover what's really inside a curry
0:41:25 > 0:41:29than one of Leicester's famous Belgrave Road curry spots?
0:41:29 > 0:41:33And I've invited along nutritionist Azmina Govindji
0:41:33 > 0:41:38to tell me if there are any wonder ingredients in curry that could boost my health.
0:41:40 > 0:41:43Azmina, I've always thought curry was really indulgent.
0:41:43 > 0:41:44Well, when you think of a curry
0:41:44 > 0:41:47you visualise that orange layer of oil on the top, don't you?
0:41:47 > 0:41:51But there are things you can do to make your curry really healthy
0:41:51 > 0:41:54and some of the traditional spices and ingredients can actually be good for you.
0:41:54 > 0:41:57I have to confess, I've never made it at home
0:41:57 > 0:41:59cos I've always thought it was really complicated.
0:41:59 > 0:42:03Most curries have the same basic steps, it's easier than you think.
0:42:03 > 0:42:06Chef Hamid is going to take us through
0:42:06 > 0:42:09the creation of a curry, step by step.
0:42:11 > 0:42:14He's going to start off with his oil or ghee.
0:42:15 > 0:42:19You can use sunflower, corn or rapeseed oil.
0:42:19 > 0:42:21- Next thing that's going in... - Are the onions.
0:42:21 > 0:42:24And the onions give you that lovely texture
0:42:24 > 0:42:26and creaminess that most curries need.
0:42:26 > 0:42:30And what's interesting is that onions are one of the best sources of a substance called quercetin
0:42:30 > 0:42:34and scientists are getting really interested in quercetin.
0:42:34 > 0:42:38While Hamid cooks up a storm, I'm off to the local vegetable market
0:42:38 > 0:42:42to investigate the power of quercetin with Dr Steve Alexander.
0:42:42 > 0:42:45He's a man who definitely knows his onions.
0:42:48 > 0:42:53So, Steve, I know onions contain this magical compound. What is it?
0:42:53 > 0:42:56It's a compound called quercetin, which are naturally occurring
0:42:56 > 0:42:59in fruit and vegetables and which is part of our diet.
0:42:59 > 0:43:01And how can it be helpful for our health?
0:43:01 > 0:43:05Well, the hypothesis goes that if you have quercetin over a number of years,
0:43:05 > 0:43:09that what you'll end up with is a much better cardiovascular system.
0:43:09 > 0:43:15Your decline that occurs naturally with age will be slowed down.
0:43:15 > 0:43:20So running up and down stairs is something you can do when you're 20 and less easy when you're 70.
0:43:20 > 0:43:23Well, even when you're 30 it becomes hard!
0:43:23 > 0:43:27So, can you tell which onions have the highest levels of quercetin?
0:43:28 > 0:43:31We can but not without doing a little bit of bio-chemistry.
0:43:31 > 0:43:33Let's do it.
0:43:33 > 0:43:36So what I did last night was I took the same amount
0:43:36 > 0:43:39of each of these three different sorts of onions
0:43:39 > 0:43:42and blended them with just a hand held blender at home.
0:43:42 > 0:43:44Mmmm, delicious.
0:43:44 > 0:43:47So this is red onion juice, white onion juice
0:43:47 > 0:43:50- And spring onions. - ..and spring onion juice.
0:43:50 > 0:43:52None of which I'd like to taste.
0:43:52 > 0:43:54So what are you going to do with them now?
0:43:54 > 0:43:56There's a dye reagent I can add to them
0:43:56 > 0:43:59which will react with the quercetin
0:43:59 > 0:44:02and generate a colour, which should be a dark blue.
0:44:02 > 0:44:04So this dye will show us
0:44:04 > 0:44:07the levels of quercetin in each of these test tubes.
0:44:07 > 0:44:09Yep. Indeed.
0:44:09 > 0:44:14So you can see that the red onion has the most quercetin in it
0:44:14 > 0:44:18because it's gone the darkest colour, compared to the other two.
0:44:18 > 0:44:21In fact when Steve tested these samples in the lab,
0:44:21 > 0:44:27he found the red onion had up to 50% more quercetin than the other two.
0:44:27 > 0:44:29So if I want to boost my quercetin levels,
0:44:29 > 0:44:32I should use red onion in my curry?
0:44:32 > 0:44:36Red onion will certainly give you a lot more than the white onion or the spring onion.
0:44:36 > 0:44:39- So a curry a day? - Could be very good for you.
0:44:39 > 0:44:41Maybe not that often though!
0:44:43 > 0:44:45The power of the onion!
0:44:45 > 0:44:48Back in the kitchen, it's reaching curry crunch time
0:44:48 > 0:44:52as more crucial ingredients are added to the mix.
0:44:52 > 0:44:56So, Azmina, it's really starting to look like the base of something now.
0:44:56 > 0:44:58Your cumin, your onions, your ginger,
0:44:58 > 0:45:01garlic and the tomatoes have just gone in.
0:45:01 > 0:45:05The interesting thing about tomatoes is that it's one of the few foods
0:45:05 > 0:45:08that gets better for you once you cook or process it.
0:45:09 > 0:45:14Tomatoes are packed full of an important nutrient called Lycopene,
0:45:14 > 0:45:17which can protect the skin against UV rays
0:45:17 > 0:45:21and which scientists think may cut the risk of certain diseases.
0:45:21 > 0:45:26The cooking process can actually increase Lycopene content by 50%.
0:45:28 > 0:45:30This is where it starts to get interesting.
0:45:30 > 0:45:32It really smells like a curry.
0:45:32 > 0:45:37You've got your chilli, coriander, cumin powder and your turmeric.
0:45:37 > 0:45:43- Really colourful.- Aren't they? And spices like this are the basis of most curries.
0:45:43 > 0:45:45There's a lot of really good research on spices.
0:45:45 > 0:45:47In fact here in the University Of Leicester,
0:45:47 > 0:45:51there's a group of academics particularly interested in turmeric.
0:45:53 > 0:45:57To find out more about turmeric's spicy secrets,
0:45:57 > 0:46:01I've invited Dr Leonie Norris to join me at the curry house.
0:46:03 > 0:46:06So, Leonie, I've heard turmeric has some amazing properties.
0:46:06 > 0:46:09But it doesn't really look like much.
0:46:09 > 0:46:11It looks like a mouldy potato.
0:46:11 > 0:46:14It does at the moment but actually what we're really interested in
0:46:14 > 0:46:18is what's inside turmeric, which is something called curcumin.
0:46:18 > 0:46:22It's curcumin that gives turmeric this lovely bright yellow colour.
0:46:22 > 0:46:24And it's what stains your fingers if you use it.
0:46:24 > 0:46:26And chopping boards and everything else.
0:46:26 > 0:46:28- Everything it touches! - That's curcumin.
0:46:28 > 0:46:31And why are you interested in curcumin?
0:46:31 > 0:46:35Well, we're interested in the actual anti-cancer properties of curcumin.
0:46:35 > 0:46:38Some studies have shown actually that Asian populations
0:46:38 > 0:46:41who consume a lot of turmeric in their diet
0:46:41 > 0:46:44have a lower incidence rate of bowel cancer.
0:46:44 > 0:46:48That's amazing that curcumin might be able to prevent cancer.
0:46:48 > 0:46:50But how does it actually work?
0:46:50 > 0:46:53What we have here are some cancer cells that are untreated
0:46:53 > 0:46:56and here we have cancer cells that have been treated with curcumin.
0:46:56 > 0:46:59Hopefully what you'll be able to see is that the curcumin-treated cancer
0:46:59 > 0:47:02cells are moving a lot slower
0:47:02 > 0:47:05and generally appear to be a lot less happy.
0:47:05 > 0:47:10So the curcumin is really slowing down the spread of the cancer?
0:47:10 > 0:47:12That's certainly what we believe in the lab.
0:47:12 > 0:47:16It appears to be inhibiting cell growth
0:47:16 > 0:47:18and it can cut off blood supply to the cells,
0:47:18 > 0:47:21which inevitably then will cause cell death.
0:47:21 > 0:47:24- It seems really powerful stuff. - It's pretty amazing.
0:47:26 > 0:47:30It's still too early to know exactly how much turmeric is needed
0:47:30 > 0:47:35in the diet to have an effect, but with clinical trials now under way,
0:47:35 > 0:47:38Leonie and her colleagues believe their research
0:47:38 > 0:47:41could lead to a real breakthrough in combating bowel cancer.
0:47:48 > 0:47:54From the heart-helping power of the onion to the cancer-busting properties of turmeric,
0:47:54 > 0:47:58it seems curry is brimming with nutritional secrets.
0:47:59 > 0:48:03I'm amazed that curry can pack such a powerful health punch.
0:48:03 > 0:48:06And now that I'm a curry chef extraordinaire,
0:48:06 > 0:48:09I'll definitely be making it more often.
0:48:16 > 0:48:20As the nation's tastes have changed, so too have our favourite foods.
0:48:22 > 0:48:27We now eat almost 50% more fresh fruit than we did in the 1970s,
0:48:27 > 0:48:30including far more exotic fruits.
0:48:35 > 0:48:42But of all our fruity favourites, there's one I have a real crush on.
0:48:42 > 0:48:44It's berries!
0:48:44 > 0:48:48Strawberries and cream, raspberry jam, blackberry crumble.
0:48:49 > 0:48:51It's the sweet taste of British summer.
0:48:54 > 0:48:59In fact, berries of all kinds are a firm national favourite
0:48:59 > 0:49:03and every year we get through a staggering 140,000 tonnes of them.
0:49:03 > 0:49:09That's enough to make a summer pudding three times the size of the Royal Albert Hall!
0:49:09 > 0:49:13But what is it that makes these juicy gems so special?
0:49:13 > 0:49:17It's the juiciness of them. They're so lovely.
0:49:17 > 0:49:19You just bite into them and "phssh".
0:49:20 > 0:49:23What do you like about strawberries?
0:49:23 > 0:49:26They taste a bit yummy, don't they?
0:49:27 > 0:49:31- How do you like to eat your berries? - We have them in our breakfast.
0:49:31 > 0:49:35If we have a lot left over, I do make jam with the children.
0:49:35 > 0:49:38But our favourite summer fruits aren't just tasty,
0:49:38 > 0:49:42they also have a powerful nutritional secret.
0:49:42 > 0:49:49One man who knows more about the benefits of the berry than most is Professor Jeremy Spencer.
0:49:49 > 0:49:53He's spent years uncovering their potent powers.
0:49:53 > 0:49:57So other than being delicious and really versatile,
0:49:57 > 0:49:59what is so good about berries?
0:49:59 > 0:50:01Well, berries, like other fruits and vegetables,
0:50:01 > 0:50:05contain vitamins and minerals which are good for our health.
0:50:05 > 0:50:08But what makes them unique is that they contain
0:50:08 > 0:50:12some compounds at quite high concentrations called flavonoids.
0:50:12 > 0:50:15Flavonoids are natural chemicals made by plants
0:50:15 > 0:50:17for their own protection.
0:50:17 > 0:50:22They protect the plant against things like UV light and insect attack.
0:50:22 > 0:50:26And when we eat them, they also promote health effects in us.
0:50:26 > 0:50:29So we've been focusing on blueberries
0:50:29 > 0:50:32because they contain a profile of about six different flavonoids.
0:50:32 > 0:50:38So you think that blueberries are the most potent of the berries?
0:50:38 > 0:50:42We do certainly find that they can have some very significant effects
0:50:42 > 0:50:45on blood pressure, on blood flow and also more recently brain health,
0:50:45 > 0:50:48- things like attention and processing speed.- What?
0:50:48 > 0:50:54So you're saying that the blueberry can help your brain function?
0:50:54 > 0:50:56That's right.
0:50:56 > 0:51:00- And not only that but it does it within about two to five hours after consuming them.- What?
0:51:00 > 0:51:03That's quite a big claim, that eating blueberries
0:51:03 > 0:51:06can increase my concentration in quite a short space of time.
0:51:06 > 0:51:09I will believe it when I see it.
0:51:09 > 0:51:12It's no surprise to me that blueberries are healthy,
0:51:12 > 0:51:14but the idea that they could boost our brain power
0:51:14 > 0:51:16sounds like science fiction.
0:51:17 > 0:51:21I want to test this remarkable theory for myself
0:51:21 > 0:51:25so I've come to Reading, where Jeremy conducts his research.
0:51:25 > 0:51:29And where better to try it out, than the local secondary school?
0:51:29 > 0:51:32To see whether Jeremy's theory really does hold true,
0:51:32 > 0:51:34we've roped in some volunteers.
0:51:34 > 0:51:36These are all sixth form students
0:51:36 > 0:51:39from Reading's John Madjeski Academy
0:51:39 > 0:51:42and they're in the middle of the most important school year
0:51:42 > 0:51:46of their lives so, if anyone could do with a brain boost, it's them.
0:51:46 > 0:51:50- No pressure! - THEY LAUGH
0:51:50 > 0:51:53- How do you find exams?- Stressful!
0:51:53 > 0:51:57Do you eat or drink anything to help you with your concentration?
0:51:57 > 0:51:59Lots and lots of energy drinks.
0:52:01 > 0:52:02Water, fruit...
0:52:02 > 0:52:05Sweets, sugar.
0:52:05 > 0:52:10- If there was something that could give you a bit of a boost, would that be appealing?- Yep, definitely.
0:52:12 > 0:52:16They don't know it yet, but these kids are our blueberry guinea pigs.
0:52:16 > 0:52:19With their help we're going to find out
0:52:19 > 0:52:23if these tiny berries can really make a difference.
0:52:23 > 0:52:27First, the class is randomly divided into two groups - red and green.
0:52:32 > 0:52:36Thank you so much for coming today and being part of our experiment.
0:52:36 > 0:52:40It's really important that you focus on the tests you're about to take.
0:52:40 > 0:52:44Next, they're given a series of specially devised exams
0:52:44 > 0:52:49to test their word recognition, concentration and memory skills.
0:52:52 > 0:52:55They're so focused on this. Proper exam conditions.
0:52:55 > 0:53:00Really focused and really quiet and really taking it seriously.
0:53:00 > 0:53:02So what's happening right now?
0:53:02 > 0:53:05They're sitting a series of tests which will asses different
0:53:05 > 0:53:08functions in their brain, so their memory,
0:53:08 > 0:53:13their speed of processing and their ability to correctly identify targets.
0:53:13 > 0:53:17OK, so the purpose of this test is to see how the kids,
0:53:17 > 0:53:20are able to concentrate normally.
0:53:20 > 0:53:23- Just their normal brain function. - Yes, exactly.
0:53:25 > 0:53:28While our students finish their brain tests,
0:53:28 > 0:53:31I get to work on the next stage of the experiment.
0:53:31 > 0:53:36I'm making them a very special mid-morning snack.
0:53:36 > 0:53:38Turn that one on.
0:53:38 > 0:53:40And we can start adding the milk to that.
0:53:40 > 0:53:44The red group are getting a super-charged blueberry smoothie,
0:53:44 > 0:53:46packed full of flavonoids.
0:53:47 > 0:53:51'The green group are also getting a smoothie but theirs is banana.'
0:53:51 > 0:53:56Delicious but not a brain-boosting berry in sight.
0:53:57 > 0:54:02None of our students know which drink they're getting or why
0:54:02 > 0:54:05but Jeremy thinks the secret powers of the blueberry
0:54:05 > 0:54:08could improve those exam scores later in the day.
0:54:08 > 0:54:12I've tried both of them and I can say that they are both delicious.
0:54:20 > 0:54:23Oh, you've got a long way to go!
0:54:25 > 0:54:27- Enjoying it?- No.
0:54:29 > 0:54:31Finished? Yes.
0:54:31 > 0:54:33Oh, there's a bit more in there.
0:54:34 > 0:54:36Nice try, nice try.
0:54:40 > 0:54:45They may not have loved them but at least they drank them!
0:54:45 > 0:54:50Thank you so much for taking part in part one of our experiment
0:54:50 > 0:54:54and for drinking the delicious drink, which so many of you loved.
0:54:57 > 0:54:59With the smoothies polished off,
0:54:59 > 0:55:02we now need to give the berries time to work their magic.
0:55:03 > 0:55:07Jeremy's research has shown that it takes roughly four hours
0:55:07 > 0:55:10for the effects to reach their peak.
0:55:10 > 0:55:13But what is it that the blueberries do?
0:55:13 > 0:55:17What is actually going on inside our students' heads?
0:55:17 > 0:55:21The scientists have discovered that the flavonoids in blueberries
0:55:21 > 0:55:23are absorbed into the bloodstream
0:55:23 > 0:55:27and then cause an increase in blood flow to the parts of the brain
0:55:27 > 0:55:29responsible for memory,
0:55:29 > 0:55:32concentration and attention to detail.
0:55:32 > 0:55:36It's this effect that Jeremy hopes will transform our teenagers
0:55:36 > 0:55:38into bright-eyed brainiacs.
0:55:40 > 0:55:43So that's the theory but has it worked?
0:55:45 > 0:55:48It's been four hours since the students had their smoothies,
0:55:48 > 0:55:50so now it's time for round two of the experiment.
0:55:50 > 0:55:54Let's see if those drinks really had an impact.
0:55:54 > 0:55:58Our valiant volunteers are given another series of brain tests
0:55:58 > 0:56:02similar to the ones they sat this morning.
0:56:02 > 0:56:06This time of day is when many students start feeling tired.
0:56:06 > 0:56:08Will blueberries be able to triumph
0:56:08 > 0:56:11over even the classic afternoon slump?
0:56:14 > 0:56:16So they're crunching the numbers now,
0:56:16 > 0:56:18going through all of the results.
0:56:18 > 0:56:20Fingers crossed it's going OK.
0:56:27 > 0:56:29OK, Jeremy. Put me out of my misery.
0:56:29 > 0:56:32Do blueberries really improve our brain function?
0:56:32 > 0:56:34Well, you'll be very pleased to know
0:56:34 > 0:56:38that in the tests so far processed today,
0:56:38 > 0:56:41the blueberry outperformed the banana in every case.
0:56:41 > 0:56:44- If you look at the...- So it really works?- It really works.
0:56:44 > 0:56:46That's amazing.
0:56:46 > 0:56:48In fact, overall,
0:56:48 > 0:56:54the blueberry smoothie drinkers did 11% better in the afternoon tests
0:56:54 > 0:56:56compared to their morning performance.
0:56:56 > 0:57:00While the banana group didn't improve at all.
0:57:00 > 0:57:04- That's a massive difference! - Quite a big difference, yes.
0:57:04 > 0:57:07The results of our study were so impressive
0:57:07 > 0:57:10that Jeremy and his colleagues hope to publish them
0:57:10 > 0:57:12as part of an academic paper,
0:57:12 > 0:57:16along with similar findings from their other experiments.
0:57:16 > 0:57:21And for our students, an 11% improvement could be the difference
0:57:21 > 0:57:25between a pass and a fail in their A-level exams.
0:57:25 > 0:57:27They ate two portions or 200 grams
0:57:27 > 0:57:30of fresh blueberries in their smoothies
0:57:30 > 0:57:35but the flavonoids should be just as effective in frozen berries
0:57:35 > 0:57:37or even blueberry puree.
0:57:37 > 0:57:41It seems incredible that something so small
0:57:41 > 0:57:43can have such a dramatic effect.
0:57:43 > 0:57:46So the next time I want to give my brain a boost,
0:57:46 > 0:57:48I know what I'll be reaching for.
0:57:50 > 0:57:53I set out to find the healthy secrets
0:57:53 > 0:57:55hidden in our favourite foods.
0:57:55 > 0:57:59And with your help, I've discovered that our supermarket staples
0:57:59 > 0:58:03have powers we'd never have imagined.
0:58:03 > 0:58:08I love the fact that coffee can help with my gym workouts.
0:58:08 > 0:58:12I have a new-found respect for the humble potato.
0:58:12 > 0:58:14And I'm amazed that eating blueberries
0:58:14 > 0:58:17can boost my concentration.
0:58:17 > 0:58:20This is the stuff we take for granted,
0:58:20 > 0:58:24so it's good to know our favourite foods can still surprise us.
0:58:48 > 0:58:52Subtitles by Red Bee Media Ltd