Trust Me I'm A Doctor (2013) s06e03 Episode Script

Season 6, Episode 3

1 When it comes to our health, it seems everyone has an opinion and everyone has an agenda.
But what's the health advice you can really trust? We're here to weigh up the evidence and use our expertise to guide you.
Through the contradictions and the confusions.
We do the research no-one else has done.
And put your health at the heart of what we do.
We listen to the questions you want answered.
And ensure you get the information you need.
We're here when you want to know the latest findings - and not just the latest fads.
I'm Michael Mosley.
In this series, I'm joined by a team of doctors.
Together, we'll cut through the hype, the headlines and the health claims.
This is Trust Me, I'm A Doctor.
Welcome to Liverpool.
We're here to do a hugely ambitious experiment with Liverpool John Moores University, all about fish oils.
Now, we know that fish oil is good for us, but what's the best way of getting it in our bodies? We'll also find out whether the plastics in food packaging are poisoning us.
Why your sex affects how much fat you should eat.
Basically, what we're saying is that women are better.
We'll discover how this little patch could be the future of brain trauma treatment.
How to spot the symptoms of an illness that can leave you blind.
And how to overcome motion sickness.
I think I'm going to go green, soon.
But first, we're always hearing about how important omega-3 is for our health.
Particularly our heart.
And to make sure we get enough, we're encouraged to eat oily fish or take fish oil supplements.
But how much difference do either of them really make to our health? Later on, we'll be doing a big experiment to find out.
But before we start, Doctor Chris van Tulleken is going to take a closer look at supplements.
The government recommends that we eat fish at least twice a week, with one portion being an oily fish like salmon or mackerel.
However, in the UK, we don't eat anything like enough oily fish.
It may be that people don't like the taste or the smell or perhaps they just don't know how to cook it, but, at any rate, lots of people prefer the convenience of fish oil supplements.
These colourful capsules are one of Britain's best selling supplements.
In 2010, we forked out about 瞿140 million on them.
But here on Trust Me, we know that you don't always get what you pay for.
So, we've decided to put these popular pills to the test, to see if they're worthy of our hard-earned cash.
Do they really contain what they say they do, and can they match the benefits that come from eating real fish? Oily fish are recommended because, well, people who eat them seem to live a bit longer, and that's because the fish are packed with nutrients, including omega-3 fatty acids.
And these fish oils are meant to have a range of benefits, including preventing heart disease.
Omega-3s help maintain healthy levels of fat in our blood and prevent blood clots.
They're also a natural anti-inflammatory.
But our bodies don't produce them, so we need to get them from external sources like certain plant oils, oily fish or supplements.
There are different types of omega-3, but the two key ones for human health from fish are called EPA and DHA.
Different health organisations suggest our combined daily intake of these fats should total between 200 and 450 mg.
Popular supplements claim to meet this level, but do they? We're going to find out if the fish oil supplements contain what they say they do, especially those key fats, EPA and DHA, and we're going to test how fresh the oil in the supplements is, because rancid oil is not good.
So, we've taken ten popular fish oil supplements and sent them to a lab for testing.
The tests were carried out by Doctor Cristina Legido-Quigley from King's College London.
The first thing we measured - was the amount of EPA and DHA in the supplements.
- OK.
And it is thought that we should be eating from 200 to 450mg daily.
And was there enough EPA and DHA in these tablets? - Yes.
Here you have at least 200mg with all of the supplements.
- OK.
So, this line is the 200 mg and all of them managed - to just get over that line? - Yes.
Our second test looked at whether the oil in the supplements had oxidised or gone rancid.
We found that one of the supplements had values of oxidation - way above the limit.
- Was that because it had gone out of date? No, it still had 11 months to go.
So, despite having 11 months left on its best-before date, one supplement we tested had gone rancid.
All kinds of things can cause this over time, such as exposure to air, heat and light.
So even if oil is good when it was manufactured, it could go rancid by the time you take it.
There's evidence that rancid oils are bad for our health.
And we also know that when oil oxidises, it starts breaking down.
With fish oil supplements, that means the EPA and DHA are chemically altered, reducing the supposed benefits they provide.
Finally, we ran a price comparison on the products we tested and the variation is shocking.
So, you can see here that you could get your yearly amount for only 瞿13.
- For 瞿13 - 瞿13.
.
.
you can get your whole year's worth with this brand? - Yes, that's right.
- Then what was the most? So, we have here this one, which would be more than 瞿300 a year.
So, the price difference ranges - from 瞿13 a year to 瞿304 a year? - Mm-hmm.
And it's exactly the same chemical constituents - in terms of the fats in the pills? - Yes.
- Amazing.
So, our tests showed that at least one of the supplements contained spoiled oil but, overall, the brands contained acceptable levels of EPA and DHA, albeit at wildly different prices.
So, if you are going to buy fish oil supplements, there are a few things you can do to maximise your chances of getting the best from them.
Look for accreditation badges, like this.
Fish oils aren't medically regulated, but companies which seek accreditation are likely to have robust quality control in place.
Make sure you check the label so you can choose a supplement with the longest possible shelf life.
And store the supplements in a cool, dry, dark place, to minimise the chance of spoilage.
Now, you might be convinced that the supplement that you take is a good one, but I'm afraid the jury is still very much out about whether or not fish oil supplements have the same health benefits as fresh fish, something we're pretty sure is good for you.
But that is exactly the kind of thing that we like to put to the test on Trust Me, so that's what we're doing later - putting fish oil supplements and fresh fish head-to-head.
Many of us are familiar with travel sickness, the scourge of family holidays, but what can you do about it? Over to Dr Saleyha Ahsan.
I suffer from motion sickness myself and I dread situations like this.
Travel sickness occurs when the brain receives conflicting messages from the eyes, which see motion, and the inner ear, which senses motion.
The resulting confusion can cause various symptoms.
The main symptoms of travel sickness that most of us will recognise are general feeling of discomfort, nausea and even vomiting, and some people might even experience headache, dizziness and cold sweats.
So, what can you do about it? Over-the-counter medications like Hyoscine and antihistamines have good evidence behind them.
But there's a drawback.
They've both got side-effects.
A common one is drowsiness.
So, are there any drug-free alternatives? When I can't drink anything else, I can drink ginger ale.
Many people swear by ginger, which has been used to prevent nausea for over 2,000 years, whereas others find acupressure bracelets helpful.
But currently, there isn't strong evidence to prove that either works for motion sickness.
I was told that if you're on a boat, if you look at the keep focused on the horizon, that helps, but it's very difficult when you're going up and down and up and down! Looking at something stable, like the horizon, can help, by synchronising your vision and your movement.
And studies have also shown that distracting yourself with music can make a difference.
If, like me, you suffer from motion sickness, then it's worth trying all these techniques, but I've come across a recent report that suggests another technique that's easy, drug-free, effective and won't cost you a penny.
I'm off to the University of Westminster to learn this trick from Professor John Golding.
First, we have to establish my baseline level of motion sickness with this bizarre-looking chair.
There's a sick bag here, which has never been used.
I might be the first.
This chair, combined with the instructions I'm following, is designed to take me to different levels of sickness.
- ELECTRONIC VOICE: - Rate symptoms.
Two.
Back.
Return.
Left.
Return.
- I feel sick.
- Right.
- OK, stop.
Now that we've established the level at which I start feeling sick, John's going to talk me through a simple technique that might help me cope better next time.
What's involved is gaining control, conscious control, of your breathing.
The best way to do it is to understand what your natural frequency is, and then learn how to actually maintain that frequency.
Why does that work and how does it work? There's a hard-wired reflex, or defence reflex, between respiration and nausea and vomiting, which means if I'm breathing, I'm not going to vomit, and equally, if I'm vomiting I'm going to close my breathing off.
So, once I've worked out what my rhythm is, I've just got to focus on that and keep that going, is that right? Yes.
Now it's up to you.
OK, best of luck.
Controlling your breathing while travelling isn't as easy as it sounds, as motion can disrupt your natural rhythm.
But John's work suggests that maintaining that natural rhythm, despite the motion, can reduce nausea.
Forward.
Return.
Just concentrate on your breathing.
- Breath nice and steadily.
- Back.
- Rate symptoms.
- One.
One, OK.
A few rounds in and my symptoms rating's already stayed lower for longer.
- Rate symptoms.
- Two.
Two, OK, doing fine.
- Left.
- I feel sick.
OK, keep your head upright, as still as possible.
By the time I actually feel sick, I've lasted quite a bit longer than I did last time.
- The breathing did help - Yeah.
- .
.
because I focused on it, actually, and it did calm me down.
Don't forget, it's a severe challenge.
Under milder conditions, the breathing might be just enough to stave things off.
If you suffer from travel sickness, I'd say it's well worth giving this breathing technique a go.
As always, you can find more information on our website.
Come back in an hour.
I might be normal then.
There's no shortage of advice in the media about the best ways to boost your immune system, but is any of this advice worth paying attention to? Over to surgeon Gabriel Weston.
It's almost impossible these days to get away from products that, it's claimed, can boost our immune system, but I've always been a bit suspicious of such claims.
Mostly because we're talking about one of the most complex aspects of the human body.
The immune system is vastly complicated, consisting of hundreds of different kinds of cells that all do different jobs, whether recognising foreign invaders, carrying messages, devouring known bacteria or learning how to fight new enemies.
To gain a rare view into this diverse system, I've come to Glasgow University.
Professors Iain McInnes and Paul Garside are studying one of the key types of immune cell, white blood cells, using a laser microscope.
It's actually very difficult to look at the immune system at work.
Cardiologists can watch the heart beat with an echocardiogram.
I don't have that immunological stethoscope, if you like, to really get into the detail of what the cells are doing.
Think about somebody who develops glandular fever, for example.
Within three or four days of getting that viral infection, they will generate in the order of seven billion cells.
That's not far short of the world's total population.
And that's why Paul and I have been working together to try and develop imaging techniques that allow us to see white blood cells in the real time, doing their job.
Wow, so, not just white blood cells on a glass slide, but actually kind of in their dynamic function.
Absolutely.
This technology can reveal individual cells moving in real time.
These are just two of the hundreds of cell types in the immune system.
The green cells gather information and pass it on to the red cells, which will respond if needed.
When the system is activated, you can see these interactions intensify.
- It's amazing to see - Yeah, no, it's very exciting.
- .
.
the cells actually moving like that.
- Yeah, it's great fun.
Isn't it? Really, really interesting.
I think one of the most important things is how dynamic the immune system is, that the cells of your immune system move and talk to each other and they also all have conversations with the tissues within which they reside, so they will talk to the cells in your skin or the cells in your gut, and it's that integrated.
And that's incredibly complex and we're only just beginning to scratch the surface of that.
Because of this astonishing complexity, it's incredibly difficult to measure whether anything that's described as boosting the immune system can really make a difference.
So, what do we know? To stay healthy, we need to get enough vitamins and minerals, and some studies have suggested that if we're deficient in, say, zinc or vitamin C, it can have a harmful effect on our immune response.
But for most of us, that doesn't mean we need to take supplements.
The truth is, if we're eating healthily, the vast majority of us will get all the vitamins and minerals we need in our diet and there's simply no evidence to suggest that taking extra amounts will enhance our disease-fighting powers.
Studies have also looked at whether herbs, like Echinacea, can help our immune system, but there isn't yet enough good evidence to back up this connection.
Probiotic products have also been linked to immune health, but the European Food Safety Authority has ruled that they can't claim to improve immune function, because of a lack of scientific proof.
But there's something else that bothers me about all this.
Even if we could boost our immune systems, is that something we really want to be doing? It seems to me that by concentrating so much on boosting, we're missing a vital point about the immune system - the importance of balance.
There are as many off switches in the immune system as there are on switches.
We tend to think of the on switches mainly, but those off switches are important.
If they fail, overactive immunity could become a problem.
That's where the immune system becomes confused and attacks our own tissues instead of invading organisms and germs.
So, a healthy immune system is one that sits in balance.
It's poised and ready to go.
Think of a catapult.
It's as if the elastic is pulled back and ready just to be released.
That's how the immune system is set in health.
What would you advise your kids or your wife or your relatives, if they said to you, "I really want to make sure that my immune function "is absolutely tiptop?" What would you say? I think the normal vitamins and minerals that we all take in a healthy, balanced diet are what you need.
It's balance in your diet, it's balance in your lifestyle, and that balances your immune system.
So, no quick fix magic wand waving, then? Not as far as I'm concerned, no.
We're learning more about the immune system all the time, but there's still so much to discover.
And its complexity means that it's unlikely to respond to any kind of quick fix.
The immune system isn't a single entity, and to function properly it needs all of its elements to work together in perfect balance, so until there is some solid evidence that taking supplements can help us with this, I'm certainly not going to be wasting my money on any so-called immune-boosting products.
Earlier on, Chris tested ten popular fish oil supplements and found that even the cheapest ones contain the levels of healthy omega-3 fats they claimed.
But do the benefits of eating omega-3 really justify the hype? And if so, are supplements as effective as eating real fish? To find out, we're setting up an experiment with 60 people in Liverpool.
Our volunteers are going to start an eight-week trial, testing the benefits of eating fresh fish versus supplements.
We're going to split our volunteers into three groups.
Group One will eat oily fish, like salmon or mackerel, twice weekly.
Group Two will take a supplement that, over the week, will provide them with the same amount of omega-3 as the oily fish group.
Our groups will be taking high but safe levels of omega-3 fats to improve the chances of seeing any changes in our eight-week study.
The third group will take a dummy pill and they'll eat white fish, which actually contains very little omega-3.
So, while they think they're getting omega-3, they're actually our placebo group.
Before they start, we're doing a range of tests, and one of the key things we're looking at is something called the omega-3 index.
This is a measure of the levels of EPA and DHA in their blood.
It tells us what percentage of the fat in their cells is actually made up of these health-boosting omega-3 fats.
A low omega-3 index is linked with an increased risk of heart attack, stroke and diabetes.
At the end of the experiment, we'll repeat all the tests and see if either the fish group or the supplement-takers have seen any improvement.
Results coming up later in the programme.
If you have a burning health question you've always wanted answered, why not send it to us via the Trust Me website? I'd like to know if there is a cure for restless leg syndrome.
Restless leg syndrome isn't jiggling your legs about when you're sitting, it's very different.
To those who have experienced it, it's unmistakable and unpleasant.
Many of us have experienced a strange sensation when we're resting, usually at night.
It's an irresistible urge to move your legs, often accompanied by unpleasant feelings like a crawling sensation under the skin.
Getting up and walking relieves it, but it really disrupts sleep, bringing with it tiredness, irritability and all the things that go with insomnia.
It's thought that one in ten people in the UK will suffer from restless leg syndrome at some point in their life.
Research is still trying to pin down what causes it.
There's some evidence that it can be alleviated by drugs that boost the level of a chemical in the brain called dopamine, which affects movement.
Now, there are drugs you can take that boost dopamine levels, and they can actually relieve symptoms or get rid of them completely, but only for a while.
The problem with these drugs is your body adapts and, so, within two years, about a third of people will see their symptoms return.
If you are taking medication, it's worth remembering that symptoms can suddenly disappear naturally, so it's a good idea to take breaks from drug treatment to see if your symptoms have cleared up on their own.
And recent research might account for why women are twice as likely to suffer from it as men.
It seems that some sufferers may have low iron levels in the parts of the brain that control movement, and that these low iron levels may be due to low iron levels in the blood overall.
And that might explain why restless leg syndrome is more common when women become pregnant, because they can become anaemic at the same time.
So, if you are a sufferer, it's worth going to your doctor, getting a blood test, checking those iron levels and seeing if you need a supplement.
Iron supplements must be prescribed by a doctor, because it's important to get the levels just right.
But if your symptoms are mild enough, other things might help.
First, try to get a bit more exercise.
There's some evidence that that can help some sufferers.
Secondly, try and do everything you can to establish a regular sleeping pattern, cutting down on caffeine and other stimulants at night.
But if your symptoms are really disrupting your sleep, do make an appointment to go and see your doctor.
From time to time, most of us will eat far more than we should in the way of fatty and sugary foods.
New research, however, suggest that overindulgence affects men and women differently.
GP Dr Zoe Williams has bravely volunteered herself as a subject to find out more.
As we saw earlier, healthy fats and oils are an essential part of our diet, but fat shouldn't make up more than about 30% of what we eat.
We all know that too much fat can cause issues with our weight and our heart health.
But a new problem that's only just coming to light is that eating a lot of fat can also affect how our bodies process other foods, in particular, carbohydrates.
Scientists here at Liverpool are finding that just how bad it is may be different depending on whether you're a man or a woman.
To find out more, I've come to meet the scientist behind the research, Dr Matt Cocks of Liverpool John Moores University.
He's going to put both himself and me on a high-fat diet for a week, to reveal how men and women differ.
This is for the whole week? Yeah.
So, this is your food for the week.
Everything you see on here, you need to eat.
- OK.
Could've been worse.
- HE CHUCKLES I see there's a lot of fat on the meat, which I wouldn't normally eat the fat on the meat.
Fat's denser, more energy dense, so you're actually going to eat maybe less food than you expected, despite the fact you've got more calories.
There isn't a single fruit on there.
- This is literally it? - This is it.
- We'll see how it goes.
- Yeah, we will.
- Give it my best shot.
Matt's been investigating how eating a diet high in fat, like this, affects our ability to process carbs.
Carb-rich foods like bread and pasta cause our blood sugar levels to rise, and that sugar is normally either used as energy or stored as fat.
But Matt believes that eating a lot of fat interferes with these processes, and causes the sugar to stay in our blood for longer, which can be harmful and lead to type 2 diabetes.
So, while we're on our high-fat diet, we'll have an occasional sugary drink, which will allow Matt to measure what happens to our blood sugar levels.
Before the diet starts, a scanner measures our body fat.
Blood tests measure our blood sugar levels.
.
.
.
and we'll wear a glucose monitor, so Matt can track how well we control our blood sugar through the week.
Day three.
Dinner time.
Over the next week, Matt and I gorge ourselves on fatty foods.
Really, really missing fruit.
And on two different days, we throw in a sugary drink.
I'm having my first sugar high! One week later - Hi, Matt.
- How are you feeling? .
.
I'm back to see what impact the diet has had on our bodies.
And whether there could be differences between men and women.
First, body fat.
Here, there's not much change.
Seven days eating all that fat hasn't made a significant difference to the total body fat in either of us.
And this is what Matt has found in his previous research.
But things get really interesting when we look at how our bodies coped with consuming sugar.
Like most women in Matt's research, my ability to control my blood sugar levels didn't get any worse, in fact, unusually, mine got slightly better.
But that's not the case with Matt.
When I finished the high-fat diet, so seven days later, my control of blood sugar is actuallygot 50% worse than it was to start with.
- 50%, wow.
- Soyeah, not good for me.
So, what that means is we need our bodies to deal with sugar in the blood very quickly, to get rid of it because we don't want it to be - there - Yeah.
- .
.
and yours is only dealing with it half as well.
Yeah, that's what we seem to be saying.
Matt's response was extreme, but his wider research confirms that men are significantly worse than women at coping with high sugar levels when they eat lots of fat.
It does seem that, particularly if a man is having a very high-fat diet, if they have sugar within that, it could have a negative effect, whereas maybe with the women who are on a high-fat diet, it might be slightly less of a a kind of a bad thing to have that sugar every now and then.
OK, so, basically, what we're saying is that women are better.
It looks like it.
Our experiment is in line with Matt's wider research, which reveals that eating a lot of fat has a significant effect on men's ability to keep their blood sugar under control.
A key step in the development of type 2 diabetes.
So, what can you do about it? Well, the best advice is don't overindulge in fatty foods.
If you do eat a lot of fat, try to avoid eating carbs in the six hours afterwards, as this is when the impact on your blood sugar is worst.
Be sparing with meals that combine a lot of fat with carbs, like burger and chips or pizza.
But if you can't resist the urge, do some exercise after the meal, because this will help use up the excess sugar that's in your bloodstream.
Even just going for a walk can help open up those blood vessels, which helps the glucose get to the muscles where it can be used.
And that might help to prevent long-lasting damage.
Coming up, the red flags we should all learn to recognise that could save our eyesight.
And we reveal our fishy findings.
But first Previously on Trust Me, we tested the effects of microwave cooking on vegetables, and concluded it may actually be better than other cooking methods at preserving some of the nutrients.
But some viewers spotted something that bothered them in our cooking method.
Some of you wanted to know if it's safe to use clingfilm in the microwave and, in particular, if there's any danger of chemicals leaching out and contaminating your food.
We thought this was well worth investigating, so we decided to put some clingfilms to the test.
Plastics contain many different chemicals.
In fact, there are over 900 that are approved for use in food packaging, and some of these can be tested to see if they migrate into our food.
So, we sent some PVC clingfilm labelled microwave-safe to Dr Emma Bradley and her team at a laboratory that specialises in this kind of testing.
Our PVC clingfilm contained a common chemical called ESBO, which is made of soy bean oil.
Now, it's a plasticiser, and what that means is that it's responsible for keeping the clingfilm flexible and stretchy.
ESBO is a good example of a chemical that lab tests have shown can migrate into food.
So we wanted to see if it did this under cooking conditions that replicated the worst possible real-life contact.
ESBO dissolves into fat, so the scientists tested the clingfilm with a couple of particularly fatty foodstuffs.
First, they microwaved it with spaghetti carbonara.
Then, for the ultimate test, they soaked it in olive oil, another very fatty substance, before heating it.
And now we have the results.
In our first test, when the clingfilm was microwaved with the carbonara, there were no detectable levels of ESBO in the food.
But in our second test, when we heated the clingfilm with olive oil, there were small amounts of ESBO in the olive oil.
But these levels were in line with legal limits.
Food safety authorities in Ireland and North America advise not to allow cling-film to touch food when you're cooking, though the UK doesn't.
And interestingly, there seems to be no particular advantage in choosing microwave-safe clingfilm.
If the packaging has no specific labelling, it will have been tested to make sure it is safe for use in all foreseeable kinds of contact with food.
So, if you do want to use clingfilm in your microwave, rest assured that our tests didn't find anything that breached EU limits.
But bear in mind one important rule when you're cooking - keep your clingfilm and your food separate to minimise any risk of chemicals leaching into your dinner.
I've been a medical journalist for many years.
Stories I've seen about plastics aren't limited to clingfilm and microwaves.
Concern about plastics and the harm they might be doing us is a much broader issue than that.
Plastic is everywhere.
A lot of our food comes wrapped in plastic.
Even things like tin cans have plastic lining.
Now, a lot of people have contacted us because they are concerned, so I want to find out what, if anything, is coming out of plastic into our food, what effect is it having on our health, should I worry about plastic? Two chemicals you may have heard about are Bisphenol A, or BPA, found in plastic food containers, and phthalates, which help make plastic flexible.
Small amounts of these chemicals can migrate from plastics into food and drink.
I wanted to find out how much is getting into me.
I sent off a urine sample so we could measure my levels of BPA and phthalates.
Then I fasted for 24 hours and sent another sample, to see if avoiding exposure to plastics in food made any difference.
After that, I ate a meal full of processed food, that's been in close contact with plastics.
Not making me feel good.
This is not what I would normally eat.
And then we measured my levels again.
What we found was that my levels dropped after my fast and rose again after my meal, which shows that some of these chemicals are getting into my body from my food and drink.
And this is true for all of us.
In fact, my baseline levels were in line with the UK average.
So, should we be worried? I sent the results to two plastics experts with very different views.
Professor Andreas Kortenkamp, from Brunel University, has some concerns about the chemicals in plastics.
The two things we've been looking at were BPA and phthalates.
Why? What it is about them that worries you? The levels you carry around with you are not dangerous, but what we need to bear in mind is that some people, for reasons we don't quite understand, have very much higher levels - and it is these who we need to protect.
- OK.
A different story is pregnant women.
It wouldn't be problematic for the women themselves, but if they have a baby, it might be.
So, why is the foetus particularly at risk? In foetal life, we have a roll of hormones.
Hormones programme development.
And phthalates interfere with this programming step.
They block, they drive down the synthesis of the male sex hormone, so very relevant to male sexual development.
And we must be very careful with any chemicals we are exposing mothers to that might actually affect this programming.
But there are committees who exist to pore over the data, to make judgments, to protect the public.
Do you think they're not doing their job? The committees are doing their job, but what's missing is a more effective implementation of measures.
But we haven't considered one other element.
We have a cocktail issue here.
What you define as tolerable exposure for one chemical in isolation will change as you take into account all the others.
The good news is that, currently, there are moves ahead at the level of the European Food Safety Authority, to begin to think about ways how this can be done.
- Beginning to think? - Yes.
OK, right.
So you don't accept the argument that science has progressed to such a degree that these sort of mistakes that we've seen in the past, with chemicals where they're deemed to be safe and then they turned out not to be safe, - that's just not going to happen? - No, I don't think so.
So Also, you see, our ability to evaluate these chemicals properly, toxicologically, cannot keep pace with the speed with which industry turns out new chemicals and uses them.
So, the only option is better regulation.
For example, by restricting the use of certain of these plasticiser chemicals in plastics.
I personally believe that we, in the future, we won't be able to live without plastics, so we have to make that safe.
My next expert is Dr Nick Plant, a toxicologist at the University of Surrey.
He's part of the committee of toxicity that advises on safe levels of these chemicals.
How do you assess the safety of these chemicals? The really important tests are those done in animal models, because they allow us to look at the whole-body effects of chemicals.
So, traditionally, what we do is to test these chemicals at a range of doses.
We would identify the level that you can give to an animal that has no adverse effects, no side-effects.
Now, normally, we would then go 100 times lower than that to set what we call a tolerable daily intake.
Are you at all concerned about male foetuses? Both BPA and the phthalates, we know in animal models will cause effects on reproduction and development.
But the level of exposure that you have to the chemicals means that the risk to you is very, very low.
Is there a risk of the so-called cocktail effect? We know that for certain chemicals, when you mix them together, you can have a larger response, so what we would do is we would use the levels of the most potent chemical in that group, so the most potent phthalate, and we'd use that to make our safety level.
And that means even if there is some synergy going on, we're still going to be within a level that will be safe for human health.
Is there a possibility that actually we're missing something? There is always the unknown unknowns.
And one of the key parts of regulation is to keep levels of chemicals as low as reasonably practicable, so we use them at the lowest level that we can.
If we want to have good food containers, if we want to have safe intensive care units, using tubing, then we have to have the plasticisers that will make that tubing soft to allow us to deliver medicines, so it's a risk that I think we have to accept to gain the benefits.
Why do you think this keeps on coming up over and over again? It comes up because we don't have a clear answer.
And that naturally makes people concerned.
And, in fact, I believe that people should always keep raising these things, because if people keep discussing it, then we keep looking at ways of reducing that exposure and therefore reducing the risk.
So, having heard both sides, should I worry about plastics? As an adult, I'm not really troubled about my own exposure, but there are concerns for unborn babies.
If you are worried, you can choose products that are BPA and phthalate-free and avoid cooking in plastics.
Visit the Trust Me website to find out more.
About one in three people who experience a serious trauma, such as a car accident or being assaulted, then suffer from post-traumatic stress disorder.
It can be really hard to treat.
Surgeon Gabriel Weston has been to California, where they are testing some really novel techniques, which involve stimulating the brain.
Post-traumatic stress disorder is normally treated with talking therapies or medication.
But these don't work for everyone, and the drugs involved can cause side-effects.
Here in California, they're trialling a new approach to the way we treat mental illness.
And it all hinges on the complex inner workings of our brain.
Every day, as we go about our lives, innumerable activities are going on in our brains.
Signals are travelling along complex networks of nerve cells, neurons are firing and chemicals are reacting.
It's an intricate system that we still don't fully understand.
But one thing we do know is that these activities can be disrupted, sometimes with devastating consequences.
Everything started when I got back on my second tour.
Armando was a US Marine who returned from active service in Iraq with PTSD.
I was blown up by a suicide car bomb and, you know, there was .
.
pieces of, you know, the hands and, you know, the jawbones and, you know, just pieces of the guy everywhere.
So, seeing something like that, I mean, obviously, for some people, it has an effect on them.
I was real jumpy.
Very paranoid.
Always checking that nobody was outside, and I just could not, could not sleep.
Extreme or prolonged trauma can interfere with the brain's ability to function normally.
What happens is that the brain gets caught in a state of hyperawareness with communication networks, chemical reactions, and the ability of the brain to process and store memory being severely disrupted.
This is why PTSD sufferers can be left feeling anxious, agitated and tormented by flashbacks.
But the new treatment being offered at the University of California, Los Angeles aims to relieve the symptoms.
Experts here are hoping to treat PTSD by targeting those areas of the brain that have been altered by trauma.
The hope is that by applying electrical or magnetic stimulation to these points, they can reset brain activity and restore balance.
The name for this new approach is neuromodulation.
Dr Andrew Leuchter is the director of the neuromodulation division.
We're treating the brain as though it is a whole organ, and we're picking particular critical hubs of this network, and by introducing energy in specific ways, we're able to change the way the network functions.
Which parts of the brain are involved in PTSD? There are a few key areas that we've identified, specifically the amygdala, which allows us to process fear.
And the anterior cingulate, which is in the middle of the brain, that determines how vigilant we are, and the prefrontal cortex, which regulates mood and anxiety.
And by stimulating or inhibiting those areas, we're able to reset how the brain's network functions.
There are a number of different neuromodulation methods being studied here.
The first I'm going to look at is transcranial magnetic stimulation, or TMS, which uses electromagnetic pulses to create small currents in parts of the brain.
The magnet is firing at ten pulses per second, and it's introducing this repetitive burst of energy into the brain.
Depending on where we put the magnet, over which part of the brain network we're stimulating, we can relieve a number of different kinds of symptoms.
Magnetic stimulation has shown great potential in quietening down the parts of the brain that are overactive in PTSD, but it is not the only neuromodulation technique being used here.
Another is electrical stimulation.
Dr Leuchter is also trialling something called trigeminal nerve stimulation, or TNS.
Now, this takes advantage of a nerve called the trigeminal nerve, which runs from the skin of the forehead directly into the brain.
And the great advantage of this technique is that patients can use it in the comfort of their own homes.
All they need is this device, which is being tested in a US Army-funded trial where some patients get the real thing and some get a placebo.
So, we just ask the patient to place it directly on the forehead.
Armando is one of the patients involved.
All subjects have to do is turn it on and go to sleep.
The patch on the forehead works by directly stimulating the trigeminal nerve.
We use these very low energy, high-frequency electrical impulses that go in through the nerve and go to some of the deep brain areas that help to regulate things like anxiety, startle reflexes.
And what we're doing with these electrical signals is essentially rebooting the network, and we found that by doing that night after night for a series of weeks, that we're able to eliminate many of these troublesome anxiety and mood symptoms.
So, Armando, what does it feel like? The main and most important thing would be my sleep.
I was averaging two to four hours of sleep and now I'm getting a good six to .
.
nine hours of sleep some days.
I'm not getting startled as easy.
And having a better attitude on life.
That's great.
That's so great.
So far, Armando's response matches results from an earlier trial, where the severity of PTSD symptoms decreased and, for a quarter of the subjects, actually went into remission.
How far do you think this will go in the future? We're really just scratching the surface of what these neuromodulation treatments can be used for.
We have treated successfully chronic pain, obsessive compulsive disorder, different kinds of anxiety syndromes and, interestingly enough, even tinnitus - ringing in the ears.
And I think this is going to be the future of our specialty, where we're going to be able to treat these illnesses with very targeted energy treatments that'll be largely devoid of side-effects.
I'm inspired by what I've ever seen here in LA, and what's impressed me about neuromodulation isn't so much the technology.
In fact, some of these devices are simple enough to be used at home, but the fact that it provides a whole new therapy for a vast range of different illnesses.
In the UK, there are around 360,000 people who are registered as blind or partially sighted.
Now, in many cases, they have a disease and it's going to be progressive, but there are also plenty of examples where if you recognise the warning signs in time, you can actually prevent someone from going blind.
Over to Dr Saleyha Ahsan.
I'm on my way to meet a group of patients to talk about a condition that leads to around 3,000 people losing some or all of their sight every year.
But if it's caught in time, vision can be saved.
As an A&E doctor, I've seen first-hand what can happen when a disease called giant cell arteritis is diagnosed too late.
That's why I'm joining a drive to help improve early management and recognition and raise public awareness.
Giant cell arteritis, or GCA, is a condition where the arteries become inflamed, making it more difficult for blood to pass through them.
When it happens to the arteries supplying the optic nerve, it can lead to blindness.
But if it's caught in time, vision can be saved.
The problem with GCA is that it can come on suddenly and become dangerous very quickly.
And in some cases, sight can be irreversibly lost within days or even hours.
It's really important that we recognise the red flag symptoms so we can spot them and get treatment as early as possible.
GCA is more likely to affect adults over 50 and is three times more common in women.
I began to get these severe headaches.
I also had jaw ache, neck ache, ear ache and painful shoulders.
And these all got worse day by day by day.
My mobility became less.
Coming with lethargy and loss of appetite and loss of weight.
I was thinking, "Oh, it's going to be a migraine.
" But it wasn't a migraine.
It was like a cap of pain.
It was like my brain being squeezed.
My mother-in-law lost a lot of weight.
She was very, very low mood.
Very painful scalp.
Jaw pain, and when I say painful scalp, brushing her hair became impossible.
The most common red flags are headaches, especially at the temples, tenderness of the scalp, jaw pain and aches and pains.
But as the condition becomes more serious, sufferers may start to experience problems with their vision.
She'd gone to put the TV on for her mum and she said, "Oh, don't bother.
" She said, "I can't see properly out of my left eye.
" She said, "It's annoying me.
" She had flashing lights in her eyes.
She uses her iPad a lot, and she was like, "Oh, can you enlarge it for me? "I can't see it any more.
" One day, I had a sort of flash in one eye.
I actually lost the sight in this eye for about three minutes.
Just white.
Couldn't see anything with that eye.
At this stage, sufferers should see a doctor immediately so that they can be treated with steroids.
If they get these in time, it can save their sight.
They said, "Sit down there.
"Take your 70mg steroid straightaway.
" "This is You could lose your sight.
This is serious.
" Usually, patients have to remain on steroids for a few years, but, over time, the dose can be reduced, and after two to three years GCA may even disappear.
But if steroids aren't given in time, the result can be catastrophic.
Within the four hours that we were in eye casualty, towards the end, she reached round her chair and grabbed my hand and she said, "Amanda, I can't see anything.
" And she lost her sight that afternoon.
Listening to the stories of people who've experienced giant cell arteritis has been incredibly moving, and it's heartbreaking hearing about people who have lost their sight.
But the good news is that something is now being done to help prevent vision loss from GCA.
At Southend Hospital, Professor Bhaskar Dasgupta has been trialling a fast-track pathway for GCA, where at-risk patients are immediately screened using ultrasound.
What you see now is the picture of a normal temporal artery.
So, you can see the blood flow very nicely in the artery.
- So, what did it look like before? - Let's have a look.
The inflamed vessel wall can be seen on both sides.
That dark band.
And that's called the halo sign.
- It's quite - It's very, very thick.
You see the halo sign.
It's quite clear.
It's straight for treatment and you save their sight? Indeed.
This system has already been saving patients' sight, including that of Roger Kay.
I saw Professor Dasgupta, and he recognised the condition immediately, he did an ultrasound test, and showed me on the screen that that's what it was.
The outcome was that it saved my eyesight.
I'm a very lucky man.
Professor Dasgupta, if I had 瞿1 million, I'd give it to him.
The scheme in Southend has been so successful that it's now being rolled out across the country, meaning that future GCA patients are far less likely to lose their sight.
And we can all help by learning to recognise the early warning signs ourselves.
GCA isn't the only disease that can affect your vision, but it is one where we have an excellent chance of stopping the devastation of sight loss simply by spotting the red flags early.
So, if you have a bad headache with scalp tenderness, jaw pain, or any visual disturbance, then go and see your doctor immediately.
It could save your sight.
Back in Liverpool, our eight-week trial into the benefits of fish oils is coming to an end.
One group has been eating oily fish.
Another taking fish oil supplements.
And our third is a placebo group, who have been taking a dummy pill and eating white fish, which isn't rich in omega-3.
Blood tests have been analysed by Professor Graeme Close and Dr Ellen Dawson from Liverpool John Moores University.
And our volunteers are keen to find out the results.
Well, I wanted to know whether it's beneficial to have supplements because I'm getting to an age where I don't have tablets and still play a lot of sport and I want to know if I should be taking something.
- You had oily fish.
- Yeah, I did.
- And what did you make of that? Umnot that fabulous, but I managed to plough my way through it.
We wanted to find out whether fish or supplements boosted our volunteers' levels of healthy omega-3, and which were better.
So, we tested their omega-3 index.
This measures the fats in their blood and tells us what percent are omega-3.
Having a low omega-3 index is linked with heart disease and strokes.
So, time for the results.
Will eating the oily fish or taking the oily fish supplement have made any difference? When we look at this omega-3 index, we're interested in the percent.
8% omega-3 index gives us a low risk.
4%, medium, and under 4% gives is a higher risk of cardiovascular disease.
So, at the start of the trial, most people in this room were around about that 4% mark, which puts you in the high to moderate risk of a cardiovascular event.
- Was that a surprise to you? - Yes.
All three of our groups started the trial with low levels of omega-3, which puts them at increased risk of having a heart attack or stroke.
So, did the fish oil supplements make any difference? When we look at both the omega-3 supplement group and the oily fish group, there was quite a marked increase in omega-3.
We can see that in both of our omega-3 interventions, every single person had quite a good increase, with many of you moving from the high-risk to the low-risk category.
Our placebo group showed a slight improvement, perhaps because eating more white fish made their diet more healthy.
Though it's not statistically significant.
But in our study, both the oily fish and the supplement made a significant difference, and this carries real health benefits.
The recent study suggested that people who presented with the omega-3 profile greater than 6.
5 had 90% fewer cardiovascular events than those who presented with omega-3 profile less than three.
Both our oily fish and supplement group ended the trial above 6.
5%.
Keep that up and both groups should cut their risk of diabetes, stroke and heart attacks.
- What did you make of that? - That was really interesting.
Yes, I didn't realise I was in the moderate to high-risk category.
And really interesting results.
It's amazing what a difference can be - made in such a short time.
- I will definitely eat more fish.
I'm really pleased with how it's come out.
I'll certainly be having a lot more fish, definitely.
And so will my family.
There's no doubt that eating two portions of oily fish a week is a good option for getting your omega-3, and it's packed with other healthy nutrients, too.
If you'd rather take supplements, choose an accredited brand and make sure they contain more than 200mg of DEA and DHA combined.
But however you get your omega-3, make sure you do.
In just eight weeks, our volunteers boosted their levels.
I was really surprised by how many of those people started off with such low levels of omega-3.
And I was really impressed by how quickly eating the oily fish or taking the supplements made a difference.
I'm a fan of oily fish and I will certainly continue to consume it.
That's it from Liverpool and this series of Trust Me.
We will be back later in the year.
In the meantime, why not visit our website, where you can volunteer for experiments and find out more about all the things we've covered in the series.