Episode 2 Trust Me, I'm a Doctor

We're constantly being told how to live our lives.

But what's the health advice you can really trust?

In this series, we use our expertise to guide you...

..through the contradictions and the confusions.

We'll get to the heart of the debate...

..and ensure you get the information you need.

We're here when you don't know where to turn.

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.

This time, we're going to test some brand-new science.

Can we lose weight without changing what we eat?

We actually don't know what's going to happen.

Alcohol - the new guidelines are out, but what is a safe level?

We find out why diet foods could be making you fat.

-It's a shocking result.

-It really, really is shocking.

Which is healthier - microwaving or stove cooking?

And why cleaning your house could be bad for your health.

I think I'll be moving out!

THEY CHUCKLE

Welcome to Guildford.

We're here to do an experiment

to see if you can get healthier, perhaps lose a bit of weight,

not by changing what you eat, but when you eat.

But first...

over to surgeon Gabriel Weston, who has a very surprising proposition.

Diet products promise all the sweetness with none of the sugar -

a win-win situation for those of us

with a passion for the sweeter things in life.

But could low-calorie food and drink actually be making us fatter

and increasing our risk of diabetes?

Come January, after the festive excesses,

many of us seek out low-sugar products.

But all of these contain artificial sweeteners instead,

and there's the potential problem.

There's some new research that suggests that artificial sweeteners

could be making us less healthy

by interfering with the way that our bodies process sugar.

So we want to put them to the test.

Are sweeteners actually bad for us?

To find out, we're going to give this group of volunteers

artificial sweeteners for one week.

Before they begin, we're measuring their blood sugar levels.

We'll do the same at the end to see if there's a change.

High blood sugar can cause health problems like diabetes -

and many people take sweeteners instead of sugar

to try and avoid these,

as Dr James Brown of Aston University explains.

A high blood sugar level can be quite dangerous -

it can cause damage to tissues in the body, like the eye,

like the kidney, like blood vessels,

and this is why it's really important

that the body maintains blood sugar levels in a very narrow band.

So where do the artificial sweeteners fit into this?

Artificial sweeteners are interesting,

because people tend to consume them instead of sugar

in the belief that they won't cause an increase

in their blood sugar levels.

I would imagine that people take artificial sweeteners

almost thinking that having an artificial sweetener

is like not having anything at all.

I think that's the general consensus,

is that it's a replacement for sugar which is inert -

it doesn't do anything to the body.

But is that the case?

Our volunteers don't normally take sweeteners,

so our tests over the next week

will show whether these substances affect their blood sugar levels.

There are several artificial sweeteners on the market,

and we're going to test two very different ones.

50% of our volunteers will get this, benzoic sulfimide,

known on the street as saccharin.

Now, we've been using this as a sugar substitute for over 100 years.

Saccharin is, like most artificial sweeteners, a synthetic chemical

that tastes sweet but is supposed not to have the downsides of sugar.

We're going to test this granddaddy of all sweeteners

against the new kid on the block, stevia.

Stevia prides itself on being derived from natural sources -

but the question is, will either of these sweeteners affect

our volunteers' response to sugar?

Over the next week, our volunteers are taking the daily

safe limit of either saccharin or stevia.

And we're testing their blood sugar levels

to see whether there's any change.

This is the saccharin group.

And James has been taken aback by what saccharin has done to them.

Now, what we saw when we looked at the data from the saccharin group

was that after one week of taking saccharin,

their blood sugar had increased from a healthy level

to a level that suggests a risk of developing diabetes.

Wow! Now, that's not what I would have expected.

And that seems really, really scary, because people take sweeteners

because they think it's the healthy option.

The interesting thing is, numbers three, four, five and six

had a marked response to taking saccharin.

Their blood sugar really did increase.

The other individuals didn't see the same responses.

-It's a shocking result.

-Really. It really, really is shocking.

So whilst the group as a whole suffered raised blood sugar levels,

for four individuals, saccharin had a particularly bad effect.

Moving on to stevia,

we see a very different picture.

The effects of natural plant extract stevia

have never been studied like this before.

The individuals who took stevia for a week

didn't see any real change in their blood sugar levels.

-Nothing at all?

-Nothing which was marked or noticeable.

So for the first time, we seem to be demonstrating

a dramatic difference between these two sweeteners.

While stevia didn't affect any of our volunteers badly,

saccharin sent some people's blood sugar skyrocketing.

So why might this be?

Well, it seems the answer might lie inside our own bodies.

One theory as to why sweeteners might change our response to sugar

is that they alter our gut bacteria.

So we did some more tests on our volunteers

to see if their gut bacteria changed over the week they took sweeteners.

Joining us with the results

is Dr Paul Cotter from the Teagasc Food Research Centre

in Cork, Ireland.

He's found distinct changes in the gut bacteria

of all the volunteers taking saccharin.

And there was a noticeable pattern in the four individuals

who had the biggest rise in blood sugar.

Very surprisingly, when we looked at the gut microbiota

of these individuals, it was very much similar to one another,

and following the treatment with the saccharin, they also seemed

to undergo a particularly dramatic change during that period of time.

-And were you surprised by that?

-Um...

usually it's quite difficult to change microbial population -

it takes quite an amount of time -

and so to see changes over a short period is quite unusual.

It suggests there's a significant proportion of the population

who may be at risk of harm,

making themselves less well by consuming these sweeteners.

So there's a group out there that really is vulnerable

-to the ill effects of taking sweeteners?

-Absolutely.

And without checking out, for example, their gut microbiome,

it's very difficult to tell who those people are.

Our results, then, backed up by another recent study,

suggest that about half of us can be badly affected by saccharin,

found in many popular sweeteners, diet drinks and foods.

So we should all be aware.

The evidence is mounting that for some, saccharin is a bad thing.

It can significantly alter your gut bacteria

and increase your risk of developing diabetes -

the exact opposite of what you might think.

And it looks like other sweeteners like aspartame could be the same.

We don't know why these chemicals have this effect

but in our small study, it seems if you are looking

for an alternative to sugar, stevia may be a safer option.

Back in Surrey, we're setting up another brand-new experiment.

Most of us would like to eat more healthily,

but we find it difficult to change.

So Dr Chris van Tulleken has been testing, for the first time,

a novel approach which involves altering not what you eat,

but when you eat.

Thank you.

Like most people, I'd like to eat healthier, but unfortunately,

I can't stop eating the food that I love, which isn't that healthy.

Things like cheeseburgers.

So I want to try out a new theory - one that will allow me to eat

as many cheeseburgers as I want and still get healthier.

These days, we tend to eat throughout the day, snacking right

up until bedtime and giving our body a break only when we're asleep.

But scientific research suggests that giving ourselves

longer periods without eating could be very good for us.

So could simply packing our mealtimes together and, as a result,

lengthening the periods of time when we're not eating

really make us healthier?

To find out, we've recruited 16 volunteers

for a ground-breaking experiment.

They're going to take part in our unique ten-week study

here at the University of Surrey.

Service, please.

-And they're about to find out what's involved.

-Whoo!

-Look at that!

LAUGHTER AND CHATTER

Right, good morning, everyone.

Thank you for coming in. Now, I know it's early,

so we have done the right thing and we've got you all a bacon sandwich.

But you guys haven't got yours yet.

And that represents what we're doing over the next ten weeks.

Because you guys are a control group.

You are going to keep living your lives as normal,

eating what you like to eat at the times you want to eat it.

You guys are going to start your breakfast

an hour and a half later every day.

So you've still got about an hour and 28 minutes before

-your bacon sandwich arrives.

-LAUGHTER

And you're going to move dinner an hour and a half earlier,

so you're going to crunch your meals together.

And that means you're going to have three extra hours each day

where you're not eating.

You're looking really unhappy.

It's a form of really advanced torture, isn't it?

Being made to watch someone else eat a bacon sandwich.

-It's the smell.

-Yeah, the smell.

-How are the bacon sandwiches?

-Brilliant.

-Very good.

-Very nice.

So, for the next ten weeks, the blue group can carry on having

an early breakfast and eat as late at night as they like.

But the red group will have a late breakfast and early dinner,

so they have a much longer period when they're having no food at all.

But it does mean no late-night nibbles.

No midnight snacks, no late-night doughnuts,

no bowls of cereal before bed, no wine, no beer, no calories.

LAUGHTER

But on the plus side, we're saying you can eat whatever you want!

I find it hard that it's going to make much difference, really.

Yeah, I'll be really interested to see if it works.

Moving mealtimes seems like a small change.

Could it really make much of a difference

to the health of our red team?

Leading the research is Dr Jon Johnston

from the University of Surrey.

We're not asking people to change what they eat.

We're just saying, "Change the times that you eat"?

Exactly, it's just the time that counts in this case.

So I'm going to be honest - that sounds a bit unlikely to work.

I can see why you're saying that, but actually,

there's some really very good data now from studies in mice,

and even in flies, to suggest that

if you simply restrict the timing at which an individual eats,

that actually has beneficial effects for their metabolism.

-You do realise that people are not fruit flies or even mice?

-Well, yes.

Their metabolism is different. Er,

there are different social contexts, of course, for eating,

but what we're trying to do here is actually to find out,

"Can we translate the basic data from animals into humans?"

So, we're not just recreating science that you've already done -

we actually don't know what's going to happen?

That's right, we really don't know. We're very excited.

-OK, that is very exciting.

-It is very exciting.

-DUCKS QUACK

-Even they're excited!

And to see if the health of our volunteers improves when we change

their mealtimes, we're doing a whole range of baseline tests on them -

from their levels of body fat...

to their blood, cholesterol and sugar levels.

And in ten weeks' time,

we'll find out whether these measures have improved.

Could a rule as simple as eating breakfast a little bit later

and eating dinner a bit earlier really help us all be healthier?

We'll find out later in the programme.

But first, over to Dr Saleyha Ahsan.

Do you choose the fresh scents of citrus or pine

for your cleaning products?

Do you use air fresheners or scented plug-ins?

Well, we've all seen the adverts.

So here comes the science.

And it might make you think twice.

We've uncovered some new research

that suggests using scented products in our homes could be dangerous.

They contain chemicals to give them the smells we find so appealing.

And it seems those chemicals could be doing us no good at all, so...

I want to find out - how big a problem are they for our health?

And what can we do about it?

The first thing we need to know is,

what exactly does using scented products do to the air in our homes?

So, over the next week, we're going to measure just that,

with the help of six families from York,

Professor Ally Lewis, an atmospheric chemist,

and some rather scary-looking kit

that will sample the chemicals in the air.

-Hello!

-Hello!

'The air from each house will be analysed.

'When Ally looks at the levels of chemicals in the different houses,

'he can immediately see differences.

'Three have moderate levels of chemicals in the air.

'And their cleaning habits are similar too.'

We do a deep clean once a week, um, and then, the kitchen

and the rooms we regularly use probably every day.

But the Kings and Harrisons are much higher, and we think we know why.

We do like using scented candles.

We have them on, er, certainly daily.

And then came the Bissell family.

So high that Ally had to adjust the monitor inside their house.

And it turns out they use a lot of cleaning products.

I keep wiping round all the cupboards and...

-Polish the table.

-..polish the table.

I take the dog out four times a day.

Then this floor gets washed constantly from mucky feet

when he comes in from a walk.

So what exactly are the chemicals

that these everyday household products are leaving in the air?

But you can see the stand-out chemicals here are

-the big orange ones.

-Yeah.

-This is a chemical called limonene.

Limonene's got a very distinctive smell.

You can tell by the name - it's a lemony sort of smell -

-and it's used very, very widely to perfume things.

-Are they dangerous?

So, in themselves, almost all of these chemicals are perfectly safe.

However, a lot of these compounds are actually quite reactive

in the atmosphere, so once you release a compound like limonene,

it doesn't stay as limonene for ever.

When it gets into the air,

limonene reacts to form a chemical called formaldehyde.

And formaldehyde is toxic and even cancer-causing,

so not something we want in our houses.

For every two molecules of limonene we put into a home,

we form roughly one molecule of formaldehyde as a product.

We've measured formaldehyde as well in three of our houses and found

that the more limonene they use, the higher their formaldehyde levels.

So, do we need to throw out all scented products?

Well, we found the hint of an alternative solution,

and it comes from Nasa.

MUSIC: Also sprach Zarathustra by Richard Strauss

Faced with the problem of keeping the air inside an enclosed space station

chemical free, they tested a homely possibility -

house plants.

It seems they can absorb chemicals through the pores in their leaves

and break them down.

-There we are.

-Thank you.

So we're going to put them to the test here on Earth too.

-So, we have some plants for you.

-Oh, fantastic, some plants.

'We're giving our six families some house plants

'to place around their homes.

'They don't yet know our initial results,

'so they're still using all their normal household products.

'And, over a four-week period,

'we're taking more tests of the levels of limonene

'and formaldehyde in their homes to see if the plants make a difference.

'Finally, we welcome all the families to the local pub...'

So, thank you, everybody, for having our samplers in your home.

'..to discover the results.

'First, we share the baseline level of chemicals

'we found at the start of the experiment.

'Rather a shock for the Bissells.'

House four, the Bissells' house, holds a world record with us.

It's the highest concentration of limonene we have ever recorded.

I think I'll be moving out!

-LAUGHTER

-I think I might be as well!

I'm coming to your house!

'So, what happened to these very high limonene levels

'when we put the plants in?'

Well, compared with the start of the experiment,

it turns out they're actually higher.

But Ally can guess why.

There is a small increase in limonene in most homes

and that's potentially reflecting the fact that we've gone into winter

and people have begun to seal up their homes -

they've begun to close windows and doors

and make their homes more airtight.

The nights are closing in, so more scented candles being burned

I suspect is...the reason why it's increased a little bit.

Just closing windows a bit more, and lighting more candles,

have made limonene levels rise.

And this should, in turn, cause a rise in toxic formaldehyde as well.

But our results show quite the opposite.

What we do see is that the formaldehyde is lower

in all the homes after the plants were introduced than before.

In each of the three houses in which we measured formaldehyde,

over the course of our experiment, the levels fell.

It suggests that the plants might really have absorbed formaldehyde.

The plants must be doing summat, by the look on the graph here.

It is unusual that the limonene has gone up in lots of homes

and we haven't seen that increase in formaldehyde,

so I think it's something worth exploring in the future.

All our volunteers are now much more aware

of what they are using in their houses.

It's opened my eyes because I didn't think nothing of going round

the house giving it a good pshhh!

I think I would probably keep the houseplants

if there's a chance that they might be doing some good.

Definitely going to keep the plants, yeah.

This study has really surprised everyone who's been involved in it.

Just how high our levels of chemical pollution in our houses can be

and, by our own behaviour,

a few simple steps can actually bring that down.

I'm off to buy myself a new houseplant.

To find out which plants are best at absorbing chemicals,

go to our website...

bbc.co.uk/trustme

And on our website you can also ask us

any health questions you'd like answered.

And hundreds of you have done just that,

and our first question is...

What's the best way to treat dandruff?

Half the nation suffers from dandruff.

OK, so you do have a very small amount - do you see that there?

OK, yeah.

And apparently a third have actually avoided going out

because they're so embarrassed.

No dandruff that I can see in there.

So, how can we fix the problem?

Do you see, just a few little bits?

How would you react

if I told you that dandruff was actually caused by a fungus?

-It sounds like mould, doesn't it?

-Yeah, it's gross.

-It is, isn't it?

Dandruff is caused by this fungus, Malassezia globosa,

and we all have it on our scalps.

It feeds off sebum, or skin oil,

and produces a by-product called oleic acid.

Now, the problem is, this acid can irritate some people's skin.

And when this happens,

their immune system responds with a turbocharged skin cell turnover.

This means that bits of skin flake off your scalp

far more frequently than they should.

So, what can we do about this?

Well, air pollution can make the flaky immune reaction worse,

so maybe try a hat as protection.

But take it off when the sun comes out, as it seems a small amount

of ultraviolet light can tone down that immune response.

But it dandruff is still turning up in your hair,

and on your shoulders, how do you get rid of it?

Now, you might think that the flakiness is due to dryness,

but because the oil is the food of the dandruff fungus,

you need to wash your hair regularly -

at least two or three times a week -

to get rid of the excess grease and build-up of flakes.

There are plenty of anti-dandruff shampoos out there,

but which should you use?

Well, there are the coal tar shampoos.

They work by slowing down the renewal of skin cells on the scalp

and they can be great if you are itchy.

A word of warning, though - if you're fair, like me,

it can discolour your hair.

Then there are those with salicylic acid.

They basically exfoliate your scalp,

meaning the flakes end up in the water rather than your shoulder.

But these won't get to the root of the problem.

For that, you need an anti-fungal treatment.

The best anti-dandruff shampoos

are those that target the fungus directly.

And the most effective off-the-shelf anti-fungals

are miconazole and ketoconazole.

Ketoconazole shampoos are widely available from chemists,

while miconazole shampoos are widely available from...vets.

Because, in shampoo form, it's only licensed for cats and dogs.

So whilst we can't advise you use that, it has been approved

for human use in skin creams, which can be useful for a flaky scalp,

if you're bald.

Now, unfortunately, even after a few flake-free weeks,

the fungus can become resistant to these anti-fungal treatments.

And if that happens to you, you should swap to a shampoo

that contains zinc or selenium, which, although milder,

do contain anti-fungal properties.

So, if you're trying to shift dandruff, remember,

it's the fungus you need to target.

Wash your hair to keep it grease-free,

look out for the anti-fungal ingredients on shampoo bottles

and enjoy the sun.

Earlier in the programme, we embarked on our big experiment

to see whether just shifting our mealtimes can make us healthier.

Our group of volunteers are moving their breakfast later

and their dinner times earlier, packing their mealtimes together

to give them a longer period overnight when they are not eating.

And we are testing whether this is good for their health.

But there's something else I want to try out for myself.

Over the last ten years, average dinner times have shifted much later,

from 5.30pm till nearly 8pm.

And some scientists believe that eating this late in the evening

isn't doing us any good at all.

So I'm going to do an experiment on myself to find out if that is true.

And curiously, it starts first thing in the morning.

OK, so here we have a nice old-fashioned English fry-up.

It's my first meal of the day

and I'm going to have any other meal exactly like it in 12 hours' time.

On the face of it, it's not the worst experiment I've ever done,

except that in the intervening 12 hours

I'm going to have an awful lot of blood taken out of me.

After both my morning and evening meals,

the levels of fat and sugar in my blood will be measured.

Prolonged high levels of either are bad for you.

And this test will show if the time of day I eat makes a difference.

So, that was the first blood I've had taken since breakfast time.

And what should be happening is

my levels of fat in my blood should be beginning to surge upwards.

We'll find out shortly.

For the next 12 hours, it's no food, but plenty of blood sampling.

Exactly 12 hours later, I have exactly the same meal.

But will it have exactly the same effect on my body

at this time of night?

What the blood tests reveal is that when I ate in the morning,

my blood sugar got back to normal within two hours.

And the fat in my blood started to drop after about three hours.

But after exactly the same meal in the evening,

my blood sugar stayed high for much longer.

And the fat levels in my blood were still rising

even four hours after eating.

This is a quite startling result.

Clearly, eating this late at night isn't good for us.

So, what's going on?

Well, it seems we have an internal body clock

that makes us process food differently throughout the day.

So, what's the optimum cut-off point for meals?

There's only one way to find out.

Here at Surrey University, they study circadian rhythms -

what happens inside your body over the course of a day.

I volunteered to go into an isolation chamber for 24 hours.

I imagine it's going to be like a desert island -

except no view, no sunshine and no sea.

# If you're fond of sand dunes and salty air... #

In fact, I'm going to have my body monitored in every possible way

while I'm shut in the chamber.

Now, I'm not actually looking forward to this,

but it will be really interesting to see what happens.

Keeping me isolated from the outside world for a whole day and a night

allows the researchers to measure

my own internal body clock's natural rhythm.

I don't get any proper meals,

just regular small snacks to keep me going.

And every hour for 24 hours,

my blood is taken to measure levels of fat and sugar.

This is not one of my best self experiments.

There's one just down the bottom there.

The idea is to try and understand what our bodies do naturally,

so we can find out their rhythms

and discover what time is best for us to eat.

Finally, it's over.

I certainly hope it will be worth it.

Right...

And it was.

As evening approached,

the fat and sugar levels in my blood started to rise,

even though I'd had no meal,

and then fell again when it came to morning.

This was tied to the levels of a hormone in my blood called melatonin,

which tells us when to sleep.

So when I had a fry-up in the evening,

this was adding to a natural rise in my blood sugar and fat levels.

Dr John Johnson can explain why this happens.

OK, so, if you like, our bodies have developed

to be prepared for having food at a certain time of day

and to be fasting at another time of day,

geared towards taking nutrients from the blood,

storing them away in your metabolic tissues

and then at night, when you are supposedly fasting,

these metabolic stores then release energy into the blood,

so that tissues like your brain still have a good supply of energy.

-So your fat levels are rising in the early evening.

-Yes.

If you reach into the fridge and you grab, you know,

your bacon burger or whatever at 11 o'clock at night,

is that a bad thing?

Generally yes, because your body isn't expecting you to be eating

at that time of day. It's expecting you to be fasting.

And so what you find is that during that time,

when people eat a meal, the spike of things like sugar

and fat that you see in the blood after a meal is higher

if you eat at night

and that spike takes a bit longer to get down to background levels.

So if you eat most of your calories

certainly during the early part of the day

and fewer calories in the late afternoon and evening,

that will actually help your metabolism

and potentially help you to lose weight

and maintain weight loss as well.

So, there is good evidence that eating earlier can help us

be healthier and maybe even lose weight.

There's an old adage - breakfast like a king, lunch like a prince,

dine like a pauper.

And it would certainly be a good idea to avoid that fatty,

sugary food late at night when your body is least able to deal with it.

If you have to have that fry-up, have it for breakfast.

And now for another question sent in by a viewer.

And this one really surprised us.

Hi, my question is can I use WD-40 to treat psoriasis?

When you first hear about this idea, it sounds ludicrous,

using a household lubricant to treat a skin condition.

However, it turns out that quite a lot of people are claiming online

that WD-40 can cure all sorts, including skin conditions.

When you think about it more deeply, it's not that stupid.

So, many of the emollients, moisturising creams

that we use to treat dry, flaky skin conditions contain paraffin

or paraffin-like substances.

And that is probably the main ingredient in WD-40.

But there's the rub.

I say "probably" because actually the ingredients are a trade secret.

My money, though, is on the fact that some of them

are not going to be good for your skin if used long term.

And talking about money, this stuff is more expensive

than creams designed to treat dry skin.

So why would you even be tempted to try it?

Is using a scummy can from the shed somehow more manly?

Come on, guys!

It shouldn't be used to treat skin conditions,

it shouldn't be used to treat your aching joints,

however, it is a very effective lubricant, although I should say

that other water displacement products are available.

Still to come...

Is cooking food in a microwave bad for our health?

And how much alcohol should we be drinking?

But first...

Allergies are incredibly common, and worldwide they are on the rise.

Some can be fatal. So what can you do about it?

Well, here in the UK, children with a peanut allergy

are about to go through a pioneering new treatment.

Connie is 12 years old.

When she was just two,

her mother discovered that she was allergic to peanuts.

She has a life-threatening peanut allergy,

which means that her airways could constrict,

which means that she wouldn't be able to breathe properly

and ultimately she could die because of actually eating a peanut.

For Connie, even the smallest trace of peanut could trigger a reaction.

So things the rest of us take for granted can cause

both her and her family serious anxiety.

When we're eating out at restaurants,

then I get nervous or a bit frightened

cos it's not my mum cooking the food.

Allergies like Connie's can't be cured and are rarely outgrown.

So those who have them have to learn to cope with them

for the rest of their lives.

It's hard to imagine how worrying it must be to have a serious allergy,

let alone being the parent of a child

who could have a fatal reaction.

But, for Connie and her family, that anxiety could soon be over.

And that's because Connie is one of the very first children

trying out a ground-breaking new treatment for her peanut allergy.

The treatment is being offered at Addenbrooke's Hospital

in Cambridge, a world-renowned centre for allergy research.

Here, doctors are investigating what causes allergic reactions

and how they can be treated.

And push. Keep going, keep going...

Today, they are setting out to trigger a controlled reaction

in Richard, who has a peanut allergy.

Dr Shelley Dua is supervising.

What's actually going on inside Richard's body

when he's having this allergic reaction?

The body is recognising the peanut as something foreign

and your immune system is launching an allergic reaction against it,

which basically means that your allergic cells,

which are in your mouth, your throat, your stomach,

they're getting activated and releasing chemicals

that cause symptoms of an allergic reaction.

So, just inside my throat still.

You're struggling to breathe,

it feels like you're going to vomit all the time.

Your throat feels like it's swelling and closing up on you.

Now, the doctors have decided to stop this reaction taking place

at this point by giving medication.

The drug stops Richard's immune reaction

against the proteins in the peanut.

-Yeah, now that's...

-Are you feeling a bit woozy?

The latest research suggests

that allergies like this start in infancy.

Remarkably, they may even develop

before a baby has ever eaten a peanut.

It's thought they may arise when a baby's earliest contact with peanuts

is through their skin in products like skin creams or oils,

as the immune system doesn't learn that peanuts are OK to eat.

But the team here believe that they have a treatment

that can retrain children's immune systems.

And in many ways, it's beautifully simple.

Patients are given a tiny dose of peanut protein,

too small for their bodies to even recognise it as a toxin,

and then that dose is built up very, very slowly

until patients can tolerate one, two, or even five peanuts

without having an allergic reaction.

This principle has already been used to treat allergies like hay fever,

but Dr Andrew Clark is now attempting to apply it

to potentially fatal food allergies in children like Connie.

The aim for us is that you are able to then eat foods

that haven't got buckets of peanuts in.

But it's actually to say, you know, we've got this food that says,

"This may contain traces of peanuts." Is it safe to eat?

-And we think that will be safe for you to eat once you're treated.

-OK.

What people with peanut allergies are actually reacting to

are particular proteins that form a large part of the nut.

For the treatment,

the team have pharmaceutically made peanut protein,

and Connie will start by eating the equivalent

of just one-hundredth of a nut mixed into yoghurt.

For the first time in ten years, she's knowingly eating peanut.

But she doesn't react.

Well done, well done.

-You're brilliant! You're an absolute star.

-Well done, Connie.

Over the next few months,

Connie will take a daily dose of peanut,

gradually increasing the amount

in the hope of building up her body's tolerance to it.

And the technique looks promising.

We performed a really large trial

of over 100 children with peanut allergy.

We found in the trial that we could get about 80 to 90% of them

to eat peanuts on a regular basis.

When it worked, it really improved their quality of life.

Five weeks later, on her third visit,

the team up Connie's dose to one-tenth of a peanut.

But amazingly, she still doesn't have a reaction.

This is really encouraging.

It shows her immune system is becoming more tolerant.

And it's giving her new hope.

If this works, when I go on school trips

and I'm having lunch there, then it will be good

not to have the constant worry in the back of your mind -

does this have peanuts in?

Am I going to react to it?

Connie's treatment will last for years, perhaps a lifetime.

But the hope is that there could be

even greater potential in the future.

The principle of what we are doing is really important

and it can be applied to earlier in life.

And it's possible that eventually, one day, we'll have a treatment

that infants perhaps could have

to prevent this happening in the first place.

Treatments like this one happening here in Cambridge

have the potential to change the lives of thousands of patients

suffering from severe allergic reactions.

And who knows - this research might even one day be able to

get to the bottom of what causes allergy in the first place.

But for now, what do we do if we witness an allergic reaction?

Over to Saleyha.

As an emergency medicine doctor,

I know that a severe allergic reaction can be frightening.

But you can save someone's life if you know what to do.

The group most at risk of a fatal reaction are 17-to-27-year-olds,

like these students.

And it's not just nuts that can cause reactions.

So, anyone here suffering from allergies to anything?

I'm allergic to penicillin.

I remember having a rash all over my body.

Funny story - originally thought it was Super Noodles

-because I was eating Super Noodles at the time.

-OK.

-Staple student diet, Super Noodles.

-Would have been a nightmare.

Apart from nuts and drugs like penicillin,

fish and shellfish, eggs and dairy, insect stings

and natural latex can all cause a severe reaction called anaphylaxis.

The symptoms can include an itchy or swollen mouth,

problems breathing,

a fast pulse, nausea or a skin rash.

These red flags can be symptoms of a reaction

that could quickly become life-threatening.

But there are things that you can do that could save a life.

Most people at risk of dangerous reactions will be prescribed

a device which contains an adrenaline injection.

It might sound a bit scary, but they're actually very easy to use.

A really important thing before you begin anything

is to get the person to sit or lie down.

Remove the cap and make a fist around the device.

The injection should always go into the outer thigh,

two-thirds of the way down.

With some pens, you jab firmly.

With others, you simply place and push.

They always have the instructions on the side.

Hold it in place for as long as the instructions state,

then massage the area.

It's been proven that injecting adrenaline early

is the most effective way of treating anaphylaxis.

If an adrenaline device isn't available,

then keep the sufferer calm

and get them to lie down and raise their legs.

If they lose consciousness, put them in the recovery position.

And you should always call the emergency services.

This is really important

because one in 12 victims will see their symptoms return.

To spot anaphylaxis, look out for the red flags.

The most important ones are associated with airway,

breathing and circulation.

And there might be some characteristic skin rashes.

If you spot someone with these symptoms,

look to see if they are carrying an adrenaline pen.

And if they are, don't be afraid to use it.

And then call 999.

If you do these things, you could save a life.

For more information about dealing with anaphylaxis

and the new treatments for peanut allergy, go to our website...

When it comes to our health,

it seems we are constantly walking a tightrope.

We're told something is good for us.

Then it's claimed too much is bad.

Take alcohol.

One of life's guilty pleasures.

But is there any amount that's safe to drink?

Could it be positively good for you?

And how much is too much?

New UK guidelines have just been announced.

Now, both men and women are advised to drink

no more than 14 units a week, spread over three or more days.

That's less than five pints of strong lager

or five large glasses of wine in a week.

But the experts disagree about

whether this amount is bad for us or perhaps beneficial.

I'm off to hear the opinions of two leading experts

on the impact of alcohol on health.

And they happen to have very different points of view.

First up is Dr Alexander Jones, a consultant cardiologist

and clinical scientist at University College, London.

He believes alcohol can have benefits for heart health.

So what evidence is there for the benefit of drinking alcohol on heart?

Well, the best evidence comes from the large epidemiological studies.

There are large prospective studies in many thousands of people

in different parts of the world

that show that if you drink modest amounts of alcohol -

up to, say, two to three units of alcohol a day -

that you are less likely to develop

coronary heart disease or stroke later on in life.

And have there been trials where

-you allocate people to alcohol or not drinking alcohol?

-There have.

There have been a couple of studies which showed that

if they were randomised to either just eating a Mediterranean diet

or eating a Mediterranean diet

AND drinking a glass of red wine a night,

that those who drank a glass of red wine a night

had better cardiac function over time.

If there is a protective effect,

is it the alcohol or is it something else?

At the very least, alcohol itself is one of the substances.

In red wine, there are polyphenolic compounds

which are beneficial to health.

But the evidence for that is weaker than it is for alcohol itself.

In terms of the effect of alcohol on bio-markers,

like blood pressure and things like that, what do you see?

If you drink to excess, heavy drinkers actually have

a much higher risk of cardiovascular disease.

-But moderate drinkers, it tends to go down?

-It tends to decrease.

You also see changes in the level of good cholesterol, if you like.

And that increases in moderate drinkers.

And it is possible that that's beneficial

because there is an association between the level of that

and having a lower risk of heart disease and stroke.

What are the ways in which alcohol

could potentially be having a beneficial effect?

It may be that alcohol is promoting the production of nitric oxide,

which is a compound that makes the arteries in the body dilate

and reduces the stress on the heart and improves its oxygen supply.

OK, so how much is too much alcohol?

I think the guidelines are reasonable.

From the big epidemiological studies,

drinking around two to three units per day

seems about the level that is probably beneficial.

Dr Jones believes there IS a safe level of alcohol consumption

and the evidence that moderate drinking has a positive effect on heart health stands up.

But others disagree.

Professor Tim Stockwell is Director of the Centre for Addiction Research

at the University of Victoria in Canada.

He has advised the UK Government on alcohol guidelines

and is sceptical about the supposed benefits of drinking.

If you're going for a zero-risk approach, nobody should drink.

There's 60 different ways at least

that alcohol can make you unwell or kill you.

And drinking at about the UK drinking guidelines

of three or four units a day for a man,

there's a 23% increased risk of prostate cancer at that level.

And there'd be 10% fewer deaths from breast cancer

if there was no drinking in the world.

Do you think alcohol is beneficial at all?

I think it's important that we take a sceptical look at the evidence

because there's a lot of bad science out there.

So, you think the studies which suggest that moderate drinking

is protective of the heart are deeply flawed?

They are too simple.

It seems to be too good to be true.

If you follow up people over many years

and find they're light drinkers, hey presto,

you find they have a lower risk of many disease than does an abstainer.

However, there are studies coming out of the UK

looking at young adults who have never drunk,

and what's different about them,

it appears that the abstainers tend to have poorer health

and be poorer - they have less income.

So, already, before you start off on this journey,

where you may get selected

to be part of one of these medical studies later in life,

the abstainer group is full of people in poor health already.

So when they get to be compared with these moderate drinkers

who are cutting the fat off their bacon and exercising every day,

they've got an even less good chance.

But we've now got more decent studies

where they didn't have that bias.

And in those studies, there was no evidence of protection.

It's such a wonderful thing to believe,

if only it was true, that alcohol was really prolonging our lives.

-And do you drink?

-I do, yeah.

-In spite of this.

-But more cautiously than I used to.

-OK, how cautious is cautious?

-Probably seven or eight drinks a week.

-OK.

You've been in the field for a long time. One piece of advice -

-what would it be?

-Abstinent days. Possibly abstinent months.

And if you actually don't miss the stuff, abstinent years.

THEY LAUGH

But assuming you do occasionally want a drink, how much?

I think it's probably fine to have three or four drinks

on an occasion and not to do that more than once or twice a week.

-And just otherwise have one or two drinks now and again.

-Thank you.

Abstinent years. Abstinent decades!

-That's going to be a challenge.

-Yes.

So, for Professor Stockwell,

the evidence for health benefits just doesn't stack up.

And abstinence is a good thing.

But what do I now believe?

Having listened to both of them,

I do understand this is a really confusing picture.

I do believe that the equivalent of, say,

a glass of red wine every so often

is not going to do you any harm

and might, just might, do you some good.

So I shall sip my wine and feel good about it.

And now another question you've sent in for us.

Does microwaving my food make it any less healthy?

I'm not at all surprised that people want an answer to this question.

The internet is full of reports, articles and blogs

claiming that microwaves pose a serious threat to our health.

If all these stories are to be believed,

the humble microwave is actually responsible for damaging proteins,

poisoning us with toxins and sucking all the nutrients out of our food.

It all sounds pretty sinister.

But what does this mean, and is any of it actually true?

Well, like most conspiracy theories,

this one comes with a tiny grain of truth

mixed in with a lot of misunderstanding

and some pretty dubious interpretations

of what microwaves actually do.

# I'm spinning around... #

The aptly named microwave oven uses microwave radiation to heat food.

All that these microwaves do

is cause water molecules in the food to vibrate,

generating heat that spreads through the surrounding molecules.

Now, it has been claimed that this damages proteins

and destroys nutrients in our food.

But is any of this true?

Well, the short answer is yes.

But that's not as terrible or as unusual as it sounds.

Actually, what happens in a microwave is no different

from what happens on a stove.

Heating by any method changes proteins and nutrients.

In fact, when you boil vegetables in water,

you can lose even more goodness

because the nutrients that were in the veg

tend to end up in the water, which you then throw away.

So, if you want to cook in a way that best preserves nutrients,

what you actually need are shorter cooking times

that limit the exposure to heat

and a cooking method that uses as little water as possible.

And when you look at it like that, a microwave is a good bet.

In fact, studies looking at vitamin C have shown

that levels in food can be higher after microwave cooking

than after boiling.

So if you like using the microwave, carry on.

In some cases, your food might actually be more nutritious.

Ten weeks ago, we put 16 volunteers on a diet with a difference.

After measuring their body fat, their cholesterol levels

and their blood sugar levels, we split them into two groups.

The blue group changed absolutely nothing.

They ate whatever they wanted whenever they wanted.

But the reds brought their meal times closer together

and banned snacking in the evening,

giving them three extra hours in the day when their bodies are fasting.

We're testing a new scientific theory

that this can make you healthier and maybe even lose fat.

It works in animals, but how did our human guinea pigs get on?

I found it really hard not being able to have a glass of wine

in the evening or have nibbles in the evening,

mindlessly watching telly.

That's the hardest part.

It's quite hard to get all your wine drinking done by 6pm.

It is, it is.

But Dr Jon Johnston from the University of Surrey

has now taken their body measurements and blood samples again

and has the all-important results.

Have their efforts been worthwhile?

Well, it's good news for the restricted-time feeding group,

who ended up looking healthier in some of our measures.

So, what do we mean by that? They look healthy to me.

-Well, of course...

-But so do these guys.

So, firstly, they had lower percent body fat.

Secondly, they had lower fasting blood sugar.

-And thirdly, they had lower fasting blood cholesterol.

-Wow!

Amazing!

So, by simply bringing their mealtimes closer together,

our red group's blood sugar, cholesterol

and body fat all fell significantly

in just a few weeks.

It's an outstanding result.

These are very important things to change.

I mean, these are big risk factors

for dying of things like strokes and heart attacks.

That's right, these are certainly some of the major risk factors

for cardiovascular disease and even diabetes.

So, if these effects can be maintained over time,

potentially they have very important benefits.

Why does simply changing those mealtimes work? Do we know?

There are probably two possible explanations for this at the moment.

My personal favourite because of my research interest

is that you are eating at a time of day

when your body metabolism rhythms are expecting you to be eating food.

So your body can deal with those calories more efficiently

than if you eat, for example, during the night.

However, these guys have also had a longer fasting duration every day

and it may be that the fasting in itself

is having some important effect. At the moment, we just don't know.

But I think it's great we're actually seeing a positive result.

Is this a thing you're going to keep doing?

I will definitely carry on.

I think it's fantastic to have such positive changes. It's fantastic.

THEY CHEER AND LAUGH

I love things like this because it's such a simple rule of thumb.

And you don't have to do it the whole time.

But for mornings where you don't have much on, or evenings

when you're not out socialising or eating with friends,

it's just planted that little seed in my mind that

maybe at 11 o'clock at night I won't reach for another cheeseburger.

That's it from Guildford. Next time we're in Glasgow,

looking at the secrets of the Mediterranean diet

and carrying out a huge experiment to see if you can get

the benefits of that diet while making very little effort.

We'll be finding out whether we should all become vegetarian

and whether beards are really unhygienic.

# I just made an appointment for a special rendezvous

# To see a man of miracles and all that he can do

# Doctor, I want you

# Mm, my doctor, wanna do

# I can't get over you

# Doctor, do anything that you wanna do... #