0:00:04 > 0:00:07When it comes to our health, it seems everyone has an opinion.
0:00:08 > 0:00:11But what's the health advice you can really trust?
0:00:14 > 0:00:18We're here to weigh up the evidence and use our expertise
0:00:18 > 0:00:19to guide you...
0:00:19 > 0:00:22..through the contradictions and the confusions.
0:00:25 > 0:00:28We do research no-one else has done,
0:00:28 > 0:00:31and put your health at the heart of what we do.
0:00:32 > 0:00:36We listen to the questions you want answered.
0:00:36 > 0:00:39And ensure you get the information you need.
0:00:41 > 0:00:43We're here when you want to know the latest findings
0:00:43 > 0:00:46and not the latest fads.
0:00:47 > 0:00:49I'm Michael Mosley and, in this series,
0:00:49 > 0:00:51I'm joined by a team of doctors.
0:00:51 > 0:00:54Together, we'll cut through the hype,
0:00:54 > 0:00:56the headlines and the health claims.
0:00:58 > 0:00:59This is Trust Me I'm A Doctor.
0:01:04 > 0:01:06Hello, and welcome to Trust Me.
0:01:06 > 0:01:10Today, we're in Leeds where we're carrying out an Olympic-grade test
0:01:10 > 0:01:14to see which forms of exercise are best for bones.
0:01:15 > 0:01:20Also in the programme, could a germ-free home make you ill?
0:01:20 > 0:01:24Is it healthier to be a night owl or a morning lark?
0:01:24 > 0:01:28I was up early, I've had my coffee. What have you been doing? Nothing!
0:01:28 > 0:01:32And health advice on the internet, can you trust any of it?
0:01:32 > 0:01:34But first...
0:01:34 > 0:01:37..we all know that exercise is good for your heart, your lungs
0:01:37 > 0:01:39and your brain.
0:01:39 > 0:01:42But there is one system that's often overlooked - your bones.
0:01:47 > 0:01:51As we get older, our bones become less dense which can,
0:01:51 > 0:01:54ultimately, lead to them becoming weak and porous.
0:01:54 > 0:01:57And much more prone to fractures.
0:01:59 > 0:02:03Studies have shown that exercise can slow, even reverse, this decline,
0:02:03 > 0:02:06but what is the best type of exercise you can do
0:02:06 > 0:02:09in order to get maximum bone strength?
0:02:10 > 0:02:12We've all heard that calcium
0:02:12 > 0:02:14and vitamin D are essential for healthy bones.
0:02:15 > 0:02:18But exercise also keeps our bones strong by putting them
0:02:18 > 0:02:22under stress, subjecting them to jolts and shocks.
0:02:22 > 0:02:25Surprisingly enough, this is essential for bone health
0:02:25 > 0:02:29because each jolt sends signals to bone cells,
0:02:29 > 0:02:31telling them to grow back stronger.
0:02:32 > 0:02:35To find out which kind of exercise does this best,
0:02:35 > 0:02:38we've teamed up with Leeds Beckett University.
0:02:39 > 0:02:43Dr Karen Hind, an expert in bone health,
0:02:43 > 0:02:45is helping us carry out the unique study.
0:02:47 > 0:02:48So, from the age of 35,
0:02:48 > 0:02:52we lose approximately 0.5% of bone mass per year.
0:02:52 > 0:02:54That's very depressing!
0:02:54 > 0:02:58That is actually accelerated once ladies hit the menopause
0:02:58 > 0:03:00and once men hit around the age of 50.
0:03:00 > 0:03:03Exercise will make a massive difference to your ability
0:03:03 > 0:03:05to maintain your bone density.
0:03:06 > 0:03:11We and the Leeds team have recruited elite male and female athletes,
0:03:11 > 0:03:15including Olympic medallists from three very different sports.
0:03:17 > 0:03:21We want to see exactly how each sport has affected their bones,
0:03:21 > 0:03:25so we can learn what type of exercise might be of benefit
0:03:25 > 0:03:27to all of us.
0:03:28 > 0:03:32We've recruited cyclists from two different racing teams...
0:03:33 > 0:03:35..cricketers...
0:03:37 > 0:03:40..and gymnasts.
0:03:41 > 0:03:45Each of the sports have different movement and physiological demands.
0:03:45 > 0:03:47And by looking at those different movements
0:03:47 > 0:03:50and then looking at bone density, we can actually get an idea
0:03:50 > 0:03:54of what specific exercises might be beneficial.
0:03:56 > 0:04:00Each of our athletes get a type of X-ray called a DEXA scan
0:04:00 > 0:04:04to measure the bone density in their hips and spine,
0:04:04 > 0:04:06two common areas for fractures, as we age.
0:04:09 > 0:04:11We'll compare their results to the average bone density
0:04:11 > 0:04:14for people of their age and gender.
0:04:15 > 0:04:17Studying elite athletes will allow us
0:04:17 > 0:04:21to identify any changes in bone density that may be caused by
0:04:21 > 0:04:26the particular movements involved in these different types of exercise.
0:04:27 > 0:04:30So, we've got tumbling and somersaults,
0:04:30 > 0:04:33so that's, like, quite a lot of impact on our landings.
0:04:33 > 0:04:36We talk about muscle content, fat content but we've never,
0:04:36 > 0:04:38ever looked at bone density.
0:04:38 > 0:04:41I wouldn't be able to say what the results are going to end up like.
0:04:41 > 0:04:43We shall see!
0:04:43 > 0:04:44We shall see, indeed.
0:04:44 > 0:04:50Karen has now scanned all our elite athletes and the results are in.
0:04:53 > 0:04:57Time to find out which exercise best bolsters bones and what you can do
0:04:57 > 0:05:01to minimise your risk of developing fractures later in life.
0:05:02 > 0:05:05We've brought back one male and one female representative
0:05:05 > 0:05:07from each of our sports.
0:05:07 > 0:05:09OK, so, results time.
0:05:09 > 0:05:11First, the gymnasts.
0:05:11 > 0:05:14We're pleased to say that your bone density did come out
0:05:14 > 0:05:18at 17% higher than the reference range for your age.
0:05:18 > 0:05:20- Fantastic.- Whoo!
0:05:20 > 0:05:23That's for the women. And the same story with men.
0:05:23 > 0:05:26So, 14% above average at the spine.
0:05:26 > 0:05:29Really, really very good, actually.
0:05:29 > 0:05:32For our gymnasts, the results for both the spine
0:05:32 > 0:05:35and the hips were significantly better than average.
0:05:36 > 0:05:38Next, what about our cyclists?
0:05:38 > 0:05:42We expect the cyclists to be very fit but are they bone fit?
0:05:42 > 0:05:47With the ladies, we did find a 6% lower bone density overall
0:05:47 > 0:05:50than average, in terms of bone strength at the spine.
0:05:50 > 0:05:52And, for the men, 9% lower than average.
0:05:52 > 0:05:55So, lower than average, which is kind of surprising.
0:05:57 > 0:06:01Strangely enough, spending a lot of time cycling can actually
0:06:01 > 0:06:04lead to weaker bones than average in the spine for both men
0:06:04 > 0:06:07and women, and weaker hips for men, too.
0:06:07 > 0:06:12And the reason is to do with the type of activity.
0:06:12 > 0:06:13Cyclists are very much weight-assisted,
0:06:13 > 0:06:16particularly this region here, so, the lumbar spine.
0:06:16 > 0:06:19And this is where we saw the more prominent
0:06:19 > 0:06:21differences between the athlete groups.
0:06:21 > 0:06:25Because a cyclist's weight is supported by their bike,
0:06:25 > 0:06:28they're not putting the kind of pressure on their bones
0:06:28 > 0:06:29that would strengthen them.
0:06:29 > 0:06:33So, while cycling is a great way to improve your fitness
0:06:33 > 0:06:35and your cardiovascular health,
0:06:35 > 0:06:38it's not so good for your bones.
0:06:39 > 0:06:42Finally, what about our cricketers?
0:06:42 > 0:06:45- I have low expectations for the cricketers.- Oh, OK!
0:06:45 > 0:06:48So, cricketers are the surprising group here.
0:06:48 > 0:06:51Cricketers, at the spine, even better.
0:06:51 > 0:06:55So, for the women, 22% above average for your age,
0:06:55 > 0:06:58and, for the men, 18% above average for your age.
0:06:58 > 0:06:59That's surprising
0:06:59 > 0:07:03because you think of cricketers as standing around an awful lot.
0:07:03 > 0:07:05You do, and you see cricketers on the field for a long time,
0:07:05 > 0:07:08but, actually, the movements employed in that sport,
0:07:08 > 0:07:11even though they're not constant and continuous all the way
0:07:11 > 0:07:14through the game, those explosive sessions might actually be
0:07:14 > 0:07:17having quite a beneficial effect for your bone density.
0:07:18 > 0:07:21So, cricket was the most favourable of the three sports
0:07:21 > 0:07:24for bone density, both in the spine and hips.
0:07:26 > 0:07:28It seems the combination of running, jumping
0:07:28 > 0:07:32and twisting has a particularly beneficial effect.
0:07:33 > 0:07:36And this indicates the kind of exercise we could all do
0:07:36 > 0:07:38to improve our bone health.
0:07:39 > 0:07:41Taking what we've found from this study,
0:07:41 > 0:07:44a bit from the gymnastics, from the cricketers,
0:07:44 > 0:07:47there was exercises that involve a bit of jumping, a bit of twisting.
0:07:47 > 0:07:48Dancing would be perfect.
0:07:48 > 0:07:51OK, so a bit of squat, ideally a bit of star jumping.
0:07:51 > 0:07:53Anything that involves a bit of leaping.
0:07:53 > 0:07:57That's even better because you're working that muscle but you're also,
0:07:57 > 0:07:59through the jumping, you're also getting
0:07:59 > 0:08:00that gravitational loading.
0:08:01 > 0:08:04That wasn't quite what I was expecting.
0:08:04 > 0:08:05I already do quite a lot of cycling
0:08:05 > 0:08:09but it seems that isn't enough for maximum bone strength so I'm going
0:08:09 > 0:08:14to have to throw in some star jumps, perhaps a bit of weight training.
0:08:14 > 0:08:17Maybe even a little bit of Zumba dancing.
0:08:26 > 0:08:28When it comes to sleep, some of us are larks,
0:08:28 > 0:08:33we enjoy an early morning. Others are owls. They prefer a late night.
0:08:33 > 0:08:36But what happens when your biological clock
0:08:36 > 0:08:38is out of sync with your alarm clock?
0:08:38 > 0:08:41Dr Giles Yeo investigates.
0:08:42 > 0:08:45For many of us, the time of day we're expected to be at work
0:08:45 > 0:08:48doesn't fit in with our body's natural rhythm
0:08:48 > 0:08:50of sleeping and waking.
0:08:50 > 0:08:54This can result in us getting fewer hours' sleep than we really need.
0:08:54 > 0:08:58And scientific evidence suggests that's not good for our health.
0:09:00 > 0:09:03Long-term sleep deprivation is linked to a whole host of different
0:09:03 > 0:09:07health problems, including increased risk of cancer and heart disease.
0:09:09 > 0:09:12For every hour's difference between your body's natural rhythm
0:09:12 > 0:09:14and your actual daily routine,
0:09:14 > 0:09:17you increase your risk of obesity by up to 30%.
0:09:20 > 0:09:24So, why do these differences occur, and what can we do about it?
0:09:24 > 0:09:28Well, research suggests some of it is down to your age and could
0:09:28 > 0:09:32explain the biggest mystery for any parent of a teenager.
0:09:32 > 0:09:35Why can't teenagers get up in the morning?
0:09:35 > 0:09:37Are they just being lazy?
0:09:38 > 0:09:41My teenage son Harry and I are going to do an experiment to compare
0:09:41 > 0:09:44which time of day our brains are most alert -
0:09:44 > 0:09:46morning or evening.
0:09:47 > 0:09:507am, and it's time for the morning test.
0:09:50 > 0:09:52Three...two...
0:09:52 > 0:09:54..one, go!
0:09:55 > 0:09:56Under time pressure,
0:09:56 > 0:09:59we have to respond to the direction of arrows on the screen.
0:09:59 > 0:10:03- Are you feeling bright eyed and bushy tailed, Harry?- No, not really.
0:10:03 > 0:10:07The test is designed to reveal our levels of attention.
0:10:07 > 0:10:10See, I was up early, I've had my coffee. What have you been doing?
0:10:10 > 0:10:11Nothing!
0:10:13 > 0:10:178:30 PM, and time for the evening rematch.
0:10:17 > 0:10:19- Are you ready?- Yeah!- OK.
0:10:19 > 0:10:22You may be good at stuff like being famous
0:10:22 > 0:10:24but, yeah, I'm good at Arrow Beam and stuff like that.
0:10:24 > 0:10:26Oh! Got that wrong.
0:10:26 > 0:10:30I'm amazing at this. I might as well be a pro gamer.
0:10:30 > 0:10:33So, how did Harry and I compare?
0:10:33 > 0:10:36For reaction time, both of us were faster in the evening.
0:10:36 > 0:10:39And for our ability to ignore distractions,
0:10:39 > 0:10:41both of us were better in the morning.
0:10:41 > 0:10:46But, for one important measure - our ability to shift focus quickly
0:10:46 > 0:10:49in response to the arrow, we're complete opposites.
0:10:51 > 0:10:52I did much better in the morning
0:10:52 > 0:10:54while Harry did better in the evening.
0:10:56 > 0:10:58So, his brain really does seem to work
0:10:58 > 0:11:00on a different daily rhythm from mine.
0:11:00 > 0:11:05In fact, everybody has what is known as a "chronotype"
0:11:05 > 0:11:08which determines what time of day you're at your best.
0:11:09 > 0:11:13It's set by a part of our brain that acts as our master body clock
0:11:13 > 0:11:15and sets our daily rhythm.
0:11:15 > 0:11:19Recent research suggests that as timing is shifted
0:11:19 > 0:11:22by age-related hormones, such as testosterone,
0:11:22 > 0:11:24which rises sharply in teenage boys
0:11:24 > 0:11:27and falls off as they grow older.
0:11:29 > 0:11:32Now, if hormones radically alter our body clock,
0:11:32 > 0:11:34then our chronotype is going to change as we age.
0:11:34 > 0:11:36There's nothing we can do about it.
0:11:36 > 0:11:39And, for most of us, the timing of our working day
0:11:39 > 0:11:41stays roughly the same throughout our entire lives.
0:11:42 > 0:11:44If you could change it, though,
0:11:44 > 0:11:47how much difference would that really make?
0:11:48 > 0:11:51One school in London is finding out.
0:11:51 > 0:11:52It's 1.00 PM
0:11:52 > 0:11:55and these students are just arriving at school, but they're not late.
0:11:57 > 0:11:58Their lessons start now.
0:11:58 > 0:12:00At Hampton Court House Sixth Form,
0:12:00 > 0:12:03classes run from 1.30 PM to 7.00 PM
0:12:03 > 0:12:06to fit around a teenager's naturally late chronotype.
0:12:10 > 0:12:13This new school day is the brainchild of headmaster,
0:12:13 > 0:12:15Guy Holloway.
0:12:15 > 0:12:17You clearly have buy-in with the staff.
0:12:17 > 0:12:19What do they think about this?
0:12:19 > 0:12:21In-house, we talk about the "golden period".
0:12:21 > 0:12:26That period between five o'clock and seven o'clock where the quality
0:12:26 > 0:12:30of work far outperforms what might happen first thing in the morning.
0:12:30 > 0:12:32Really? 5-7?
0:12:32 > 0:12:35We have teachers who specifically want to teach at that time
0:12:35 > 0:12:38because they can get the most out of their students
0:12:38 > 0:12:42and their students work happiest and most productively at that time.
0:12:42 > 0:12:45It's a radical approach for a school to take,
0:12:45 > 0:12:47one that's being watched with interest by schools
0:12:47 > 0:12:49in other countries
0:12:49 > 0:12:51and it's certainly popular with the pupils.
0:12:51 > 0:12:53We're still putting in the same amount of work,
0:12:53 > 0:12:56the only difference is we're doing it a bit later
0:12:56 > 0:12:59and, as a direct result of that, we're more productive
0:12:59 > 0:13:00and we get more out of it.
0:13:00 > 0:13:02How has this new schedule made you feel?
0:13:02 > 0:13:05I don't have to fall asleep when I get home any more.
0:13:05 > 0:13:08Just more energy and things like that.
0:13:08 > 0:13:09So, for the students here,
0:13:09 > 0:13:13fitting the school day around their body clock seems to be working.
0:13:14 > 0:13:16Now, for most of us
0:13:16 > 0:13:19shifting our work day like that is just simply not possible.
0:13:19 > 0:13:22But there's plenty that we can do in order to bring our body clocks
0:13:22 > 0:13:26in line with our daily routine and avoid tiredness and sleep problems.
0:13:27 > 0:13:32One of the most useful things to reset your body clock is light.
0:13:32 > 0:13:35Get some natural daylight as soon as you can in the morning.
0:13:36 > 0:13:40Keep getting up at the same time every day, even on the weekends.
0:13:40 > 0:13:45And in the hour before bed, avoid screens, like phones,
0:13:45 > 0:13:47laptops and tablets.
0:13:48 > 0:13:52But my advice is, depending on what your work routine will allow,
0:13:52 > 0:13:55try not to fight your body clock.
0:13:56 > 0:13:59And maybe cut your teenage son some slack when it's midday
0:13:59 > 0:14:01and he still hasn't got up.
0:14:10 > 0:14:15Coming up - is wiping out germs in your home bad for your health?
0:14:15 > 0:14:18And when health headlines contradict each other,
0:14:18 > 0:14:21how do you know what to believe?
0:14:21 > 0:14:22But, first...
0:14:23 > 0:14:24..when we're not feeling well,
0:14:24 > 0:14:28a surprising number of us, these days, over 50%,
0:14:28 > 0:14:33would rather turn to the internet for a diagnosis than visit their GP.
0:14:33 > 0:14:35But is that wise?
0:14:35 > 0:14:37Dr Zoe Williams investigates.
0:14:39 > 0:14:42Let's say you've gorged yourself on a huge meal
0:14:42 > 0:14:47and an hour later you're having some weird cramping pains in your chest.
0:14:47 > 0:14:50Type in the symptom "chest pains" into a search engine
0:14:50 > 0:14:55and the first result that usually pops up is a heart attack.
0:14:55 > 0:14:59But, of course, it's most likely not a heart attack at all,
0:14:59 > 0:15:02probably just a nasty bout of indigestion
0:15:02 > 0:15:06and you're simply causing yourself unnecessary worry.
0:15:06 > 0:15:08So, can we ever trust the internet
0:15:08 > 0:15:11to give reliable medical information?
0:15:12 > 0:15:15If you're one of the two thirds of the British population
0:15:15 > 0:15:18that asks "Dr Google" that type of thing often,
0:15:18 > 0:15:20you may be experiencing cybercondria.
0:15:20 > 0:15:22That's medical anxiety caused
0:15:22 > 0:15:25by researching your own symptoms online.
0:15:26 > 0:15:31For me, as a GP, the internet is a fantastic tool,
0:15:31 > 0:15:34but most of the sites I use are designed for doctors.
0:15:34 > 0:15:37The online equivalent to medical textbooks.
0:15:38 > 0:15:42And if you're just using a regular browser to find information,
0:15:42 > 0:15:46the internet tends to offer the very worst-case scenario.
0:15:46 > 0:15:47So, why is that?
0:15:48 > 0:15:51One of the main reasons for this is the way that search engines hunt.
0:15:51 > 0:15:54So, if I was to put in "chest pain causes",
0:15:54 > 0:15:56the first thing that comes up is heart disease.
0:15:56 > 0:15:58So, we might think that they would list them
0:15:58 > 0:16:01with the most likely first but they don't.
0:16:01 > 0:16:04In fact, they use algorithms that rank pages
0:16:04 > 0:16:08according to how many times a key word is mentioned
0:16:08 > 0:16:10or how many clicks a page gets.
0:16:10 > 0:16:14We tend to focus on the first couple of results,
0:16:14 > 0:16:16rather than looking through the list.
0:16:16 > 0:16:19These are the ones that get clicked on again, and again,
0:16:19 > 0:16:21and that means they remain at the top,
0:16:21 > 0:16:24even if the diseases they're looking at are rare.
0:16:24 > 0:16:26Another common way to search for information is to use
0:16:26 > 0:16:28an online symptom checker.
0:16:28 > 0:16:30But, according to a recent study,
0:16:30 > 0:16:34they only make the correct diagnosis 34% of the time.
0:16:34 > 0:16:37To get the best out of these sites,
0:16:37 > 0:16:40be as specific as you can about your symptoms.
0:16:40 > 0:16:43For example, talk about the intensity of your pain
0:16:43 > 0:16:45or the duration of your vomiting.
0:16:45 > 0:16:48This can help to narrow down the results.
0:16:48 > 0:16:51But these sites still seem to struggle with differentiating
0:16:51 > 0:16:54between life-threatening illness and a simple tummy ache.
0:16:55 > 0:16:58Most of us probably know we shouldn't fully trust
0:16:58 > 0:17:01the medical content of something we've looked up online.
0:17:01 > 0:17:04And, yet, the temptation seems irresistible.
0:17:06 > 0:17:10So, why do we do it? Well, for a start, it's easy.
0:17:10 > 0:17:12For some people difficulty in getting
0:17:12 > 0:17:15a GP appointment or getting the time off work.
0:17:15 > 0:17:17But, I think there's also another reason,
0:17:17 > 0:17:19something that I call FOFO.
0:17:19 > 0:17:21And that's the Fear Of Finding Out.
0:17:21 > 0:17:26For me, the danger in using the internet to self-diagnose
0:17:26 > 0:17:29is that it can delay a visit to the doctor that could give you
0:17:29 > 0:17:32a correct diagnosis and treatment.
0:17:33 > 0:17:35But if you do want to use the internet,
0:17:35 > 0:17:39then my best advice is to stick with the NHS websites.
0:17:39 > 0:17:43The information there has been rigorously checked by clinicians,
0:17:43 > 0:17:46and there are also sections to help guide you through
0:17:46 > 0:17:49popular myths and misconceptions.
0:17:49 > 0:17:51You can find good information on the internet,
0:17:51 > 0:17:54and it's especially useful if you share it with your doctor,
0:17:54 > 0:17:59but in most cases, it's not a substitute for a visit to your GP.
0:18:07 > 0:18:08When it comes to health,
0:18:08 > 0:18:12the media often seem to perform spectacular U-turns.
0:18:12 > 0:18:15One day, coffee's good for you, the next, it's bad.
0:18:15 > 0:18:17Eating cheese makes you fat.
0:18:17 > 0:18:20No, here's a study which says it makes you thin.
0:18:20 > 0:18:24So what is going on? Are scientists changing their mind all the time?
0:18:24 > 0:18:28Are journalists getting it wrong? And how do you know what to trust?
0:18:30 > 0:18:34I've lined up two experts to help me get to the bottom of it.
0:18:36 > 0:18:39First, I'm meeting Sir David Spiegelhalter
0:18:39 > 0:18:41from the University of Cambridge.
0:18:41 > 0:18:43He's a professor of statistics,
0:18:43 > 0:18:48and regularly criticises the press for the way health news is reported.
0:18:49 > 0:18:52So, I think most people believe that the reason we get these
0:18:52 > 0:18:54confusing headlines is because the journalists are making stuff up.
0:18:54 > 0:18:56- Is that true? - There's a whole pipeline,
0:18:56 > 0:18:59from an original scientific study, that then goes through,
0:18:59 > 0:19:01it's published in a journal,
0:19:01 > 0:19:03the press officers then summarise the story
0:19:03 > 0:19:06and often tend to add in exaggerations.
0:19:06 > 0:19:07They want to get it covered.
0:19:07 > 0:19:10And so then it goes to the journalist, and my feeling is
0:19:10 > 0:19:13that the journalists often do quite a good job, but then,
0:19:13 > 0:19:16the sub-editor sticks a headline on it
0:19:16 > 0:19:18in order to get the clicks or to get attention,
0:19:18 > 0:19:21and that's again when serious distortions can occur.
0:19:21 > 0:19:24Right. I've got here some headlines. So the first one here is,
0:19:24 > 0:19:27"why Marmite could prevent miscarriages and birth defects."
0:19:27 > 0:19:29- What's wrong with that? - This does annoy me,
0:19:29 > 0:19:32because it makes it sound like this is a proven benefit on human beings,
0:19:32 > 0:19:35whereas in fact, the experiments were just done on mice.
0:19:35 > 0:19:38It's not proven to have any benefit to humans at all yet.
0:19:38 > 0:19:41But the press release never used the word "mice".
0:19:41 > 0:19:43So ideally, this headline should...
0:19:43 > 0:19:46"Why Marmite in mice could prevent miscarriages..."
0:19:46 > 0:19:49Yes, but not many people might click on that one!
0:19:49 > 0:19:50OK. Moving on, we have,
0:19:50 > 0:19:53"Why going to university increases risk of getting a brain tumour."
0:19:53 > 0:19:54Ah, this is a wonderful one.
0:19:54 > 0:19:59This was again a rather dull Swedish study that showed that richer men
0:19:59 > 0:20:01tended to have slightly more diagnoses of brain tumours.
0:20:01 > 0:20:04By the time it got to the newspaper, it was,
0:20:04 > 0:20:07"Why going to university increases the risk of a brain tumour."
0:20:07 > 0:20:09But this is implying a causation?
0:20:09 > 0:20:11A causation, that going to university increases
0:20:11 > 0:20:14the risk of a brain tumour, which I hope it doesn't!
0:20:14 > 0:20:17How would you go about getting more responsible headlines?
0:20:17 > 0:20:21More people just hammering on the doors of the newspaper
0:20:21 > 0:20:23through social media. I think this is one of the power of social media.
0:20:23 > 0:20:27The journalists see this, and they don't like it, actually,
0:20:27 > 0:20:29when their articles are being criticised.
0:20:29 > 0:20:30Thank you.
0:20:33 > 0:20:35Next up is Chris Smyth,
0:20:35 > 0:20:38Health Editor for The Times newspaper.
0:20:38 > 0:20:41He specialises in covering medical news.
0:20:43 > 0:20:45David Spiegelhalter would say that
0:20:45 > 0:20:49his biggest beef is frankly with the headline writers.
0:20:49 > 0:20:52Well, headline writing is incredibly difficult.
0:20:52 > 0:20:54You've got five usually pretty short words to summarise
0:20:54 > 0:20:55something which is, you know,
0:20:55 > 0:20:58particularly when we're talking about complex medical statistics,
0:20:58 > 0:21:02going to be very complicated, so there's just no practical way
0:21:02 > 0:21:05that it is going to tell you everything you need to know
0:21:05 > 0:21:08about the story while also making sense to that person
0:21:08 > 0:21:10flicking through their paper on the train.
0:21:10 > 0:21:12So the role of the headline is basically to advertise,
0:21:12 > 0:21:14"The story's about this topic,"
0:21:14 > 0:21:18and you can't really judge a headline unless you read the story.
0:21:18 > 0:21:22Do you see it as part of your job, holding science to account?
0:21:22 > 0:21:25Scientists get an enormous amount of public money,
0:21:25 > 0:21:27and they do wonderful things with it.
0:21:27 > 0:21:30But as with everything else, you don't want people
0:21:30 > 0:21:33to be marking their own homework and saying, "This is what we think."
0:21:33 > 0:21:36You want to have people scrutinising what they're doing,
0:21:36 > 0:21:40what they're finding. We all do. I mean, you're doing it to me now.
0:21:40 > 0:21:43You're scrutinising my journalism. Scrutiny is always helpful.
0:21:43 > 0:21:46One thing that sometimes comes up is,
0:21:46 > 0:21:48is this a drug company funding a trial
0:21:48 > 0:21:51to show that their drug is amazing?
0:21:51 > 0:21:53And this is quite a difficult issue,
0:21:53 > 0:21:56because you could not really test drugs
0:21:56 > 0:21:58if drug companies were not paying for trials,
0:21:58 > 0:22:01and some fantastic medicines have been discovered in that way.
0:22:01 > 0:22:04How you account for that is a difficult judgment,
0:22:04 > 0:22:07and I don't think it's one that's so much a journalistic problem.
0:22:07 > 0:22:10I think doctors also struggle with this.
0:22:10 > 0:22:12Thank you.
0:22:15 > 0:22:18As we've just seen, the medical stories you read in the newspapers
0:22:18 > 0:22:21are the product of a long chain of events
0:22:21 > 0:22:24which begin with the scientists and end with the headline writers,
0:22:24 > 0:22:27and at any point, someone can put their spin on it.
0:22:27 > 0:22:30Not just journalists, but medical companies,
0:22:30 > 0:22:32and their press officers too.
0:22:32 > 0:22:35It's rare that someone gets it wrong, or worse,
0:22:35 > 0:22:37deliberately sets out to mislead.
0:22:37 > 0:22:42But the same evidence can be slanted in different ways.
0:22:42 > 0:22:44So, when you do read a story,
0:22:44 > 0:22:47ask yourself, "Does this sound plausible?"
0:22:47 > 0:22:51Because extraordinary claims require extraordinary amounts of evidence.
0:22:59 > 0:23:03Over the last century, there has been a dramatic rise in asthma
0:23:03 > 0:23:05and other allergic diseases.
0:23:05 > 0:23:09Now, this is often blamed on excessive cleanliness.
0:23:09 > 0:23:13But is that true? Are there some bugs you should have in your life?
0:23:13 > 0:23:16Surgeon Gabriel Weston has been investigating.
0:23:18 > 0:23:24Last year, we spent a staggering £74 million
0:23:24 > 0:23:26on antibacterial surface wipes,
0:23:26 > 0:23:30and there's no doubt that some germs are harmful.
0:23:30 > 0:23:33You do need to be scrupulously clean, for instance,
0:23:33 > 0:23:37after handling raw meat or using the toilet,
0:23:37 > 0:23:40to avoid bugs that can make you ill.
0:23:40 > 0:23:43But all around us are countless other microbes -
0:23:43 > 0:23:46bacteria, moulds and yeasts that do us no harm
0:23:46 > 0:23:49and give our immune system a workout.
0:23:51 > 0:23:55And there are worries that wiping them out with antibacterial products
0:23:55 > 0:23:57is actually harming our health.
0:23:58 > 0:24:02The theory goes, we spray and wipe away so many natural microbes
0:24:02 > 0:24:06in our homes these days that our immune system,
0:24:06 > 0:24:08without the usual things to fight,
0:24:08 > 0:24:10turns instead against our own bodies,
0:24:10 > 0:24:13causing asthma, eczema and hay fever.
0:24:13 > 0:24:19But can using antibacterial products in our homes really be the problem?
0:24:22 > 0:24:26To help us find out, we've recruited three families
0:24:26 > 0:24:29and given each a removable kitchen worktop.
0:24:29 > 0:24:31To begin the experiment,
0:24:31 > 0:24:34they'll clean this board using antibacterial wipes.
0:24:34 > 0:24:38This will get rid of all bugs, good and bad.
0:24:38 > 0:24:42Over the next 36 hours, they'll use their kitchen as normal,
0:24:42 > 0:24:44and take regular samples from the board,
0:24:44 > 0:24:49so that we can measure how long the service remained germ free.
0:24:49 > 0:24:52And how quickly any microbes return.
0:24:54 > 0:24:58Analysing the data is microbial physiologist Dr Lynn Dover
0:24:58 > 0:25:01at Northumbria University in Newcastle,
0:25:01 > 0:25:03and it's time for the results.
0:25:04 > 0:25:07The first sample we took was after one hour, and in all cases,
0:25:07 > 0:25:09there was bacterial and fungal growth after one hour.
0:25:09 > 0:25:13So pretty much immediately after someone has disinfected
0:25:13 > 0:25:16their surface, these things are now beginning to regrow again.
0:25:16 > 0:25:19Yeah, and that progressed over the next 36 hours.
0:25:19 > 0:25:21So, as you can see, after six hours, eight hours
0:25:21 > 0:25:23and 12 hours, there's progressively more.
0:25:23 > 0:25:25This 12-hour sample is quite dramatic.
0:25:25 > 0:25:28As you can see, there were lots of different types of fungi.
0:25:28 > 0:25:29They have totally covered the plate.
0:25:29 > 0:25:32I imagine if I did it after two minutes, we'd probably find something.
0:25:32 > 0:25:35Where do all these bacteria and fungi
0:25:35 > 0:25:37that end up on these plates come from?
0:25:37 > 0:25:39The whole environment is absolutely teeming
0:25:39 > 0:25:41with microorganisms and life.
0:25:41 > 0:25:44They're from our bodies, they're from the air around us,
0:25:44 > 0:25:47little bits of skin that come off that form household dust,
0:25:47 > 0:25:51just land on the surface and they carry bacteria and fungus with them.
0:25:52 > 0:25:55So, no matter how well an antibacterial product
0:25:55 > 0:25:56has cleaned a surface,
0:25:56 > 0:25:58the bacteria, yeasts and moulds
0:25:58 > 0:26:00that are everywhere in the environment
0:26:00 > 0:26:03begin to reappear almost immediately.
0:26:03 > 0:26:07It means that using antibacterial products
0:26:07 > 0:26:12is not affecting our exposure to microbes as much as we thought.
0:26:12 > 0:26:15They're all around us all the time,
0:26:15 > 0:26:16so it's just not realistic
0:26:16 > 0:26:20to blame the rise of allergies on these products alone.
0:26:20 > 0:26:24But if our cleaning habits aren't to blame, what is?
0:26:26 > 0:26:29To find out, I'm having a picnic with Dr Claire Lanyon,
0:26:29 > 0:26:33a microbiologist from Northumbria University.
0:26:35 > 0:26:38She believes the problem is that we're not exposing ourselves
0:26:38 > 0:26:41to enough of the bugs found in nature,
0:26:41 > 0:26:46and one way to do that is to spend more time in places like this.
0:26:47 > 0:26:51Exposure to microorganisms is actually what reduces the incident
0:26:51 > 0:26:54of you developing allergies in certain situations.
0:26:54 > 0:26:57I think the key point is diversity.
0:26:57 > 0:27:01We should be exposing ourselves to lots of different varieties of them.
0:27:01 > 0:27:03Bacteria don't live as single entities,
0:27:03 > 0:27:06they live as a community, and the community is constantly
0:27:06 > 0:27:09responding with each other and with us.
0:27:10 > 0:27:14As the microbes interact with our bodies and with each other,
0:27:14 > 0:27:18they make by-products that can help strengthen our immune system.
0:27:18 > 0:27:21And they produce something called secondary metabolites.
0:27:21 > 0:27:24Now, some of these are antibiotics,
0:27:24 > 0:27:27such as what we've utilised and used to fight infections.
0:27:27 > 0:27:30So these little defence mechanisms that the bacteria have
0:27:30 > 0:27:34are constantly shaping our immune response.
0:27:35 > 0:27:38In an average ten square metres of parkland,
0:27:38 > 0:27:42there are hundreds of varieties of generally harmless microbes.
0:27:44 > 0:27:47And encountering some of them could be a key way
0:27:47 > 0:27:49to help your immune system.
0:27:50 > 0:27:52So your advice, then, would be
0:27:52 > 0:27:55to increase our exposure to lots of
0:27:55 > 0:27:57different kinds of organism?
0:27:57 > 0:28:00Absolutely. Being exposed to microorganisms is a good thing.
0:28:00 > 0:28:02- I will say cheers to that.- Cheers!
0:28:03 > 0:28:06So, it seems that for a healthy immune system,
0:28:06 > 0:28:09you need more germs in your life, not fewer,
0:28:09 > 0:28:13and the wider the variety you encounter, the better.
0:28:13 > 0:28:17So my advice is, vary your diet,
0:28:17 > 0:28:21get out in the outdoors, keep a pet, if you like,
0:28:21 > 0:28:24get your hands dirty, and whatever you do,
0:28:24 > 0:28:26don't waste another minute of your life
0:28:26 > 0:28:29trying to keep your house spotless.
0:28:37 > 0:28:39That's it for this series.
0:28:39 > 0:28:43Visit our website to find out more about the stories in this
0:28:43 > 0:28:46and all the other series of Trust Me, I'm A Doctor.
0:28:46 > 0:28:50# I just made an appointment for a special rendezvous
0:28:50 > 0:28:55# To see a man of miracles and all that he can do
0:28:55 > 0:29:00# I checked in at reception, put my hat onto my lap
0:29:00 > 0:29:03# And when he walked in dressed in white
0:29:03 > 0:29:05# I had a heart attack
0:29:05 > 0:29:07# Doctor, I want you
0:29:07 > 0:29:10# Ooh, my Doctor Wanna Do
0:29:10 > 0:29:13# I can't get over you... #
0:29:13 > 0:29:15Subtitles by Red Bee Media