Episode 1

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0:00:06 > 0:00:10We are constantly being told how to live our lives.

0:00:10 > 0:00:13But what's the health advice you can really trust?

0:00:17 > 0:00:22In this series, we use our expertise to guide you

0:00:22 > 0:00:25through the contradictions and the confusion.

0:00:32 > 0:00:35We'll get to the heart of the debate.

0:00:36 > 0:00:39And ensure you get the information you need.

0:00:46 > 0:00:49We're here when you don't know where to turn.

0:00:52 > 0:00:56I'm Michael Mosley. In this series, I'm joined by a team of doctors.

0:00:58 > 0:01:03Together, we'll cut through the hype, the headlines, and the health claims.

0:01:03 > 0:01:06This is Trust Me, I'm A Doctor.

0:01:15 > 0:01:19It's a new year and a new you.

0:01:19 > 0:01:22So welcome to a special edition of Trust Me, I'm A Doctor,

0:01:22 > 0:01:24coming from Manchester,

0:01:24 > 0:01:27a city where apparently people have increased their activity

0:01:27 > 0:01:31levels more in the last year than anywhere else in the UK.

0:01:33 > 0:01:37To welcome the New Year, we start with a cheat's guide to exercise.

0:01:37 > 0:01:42We'll show you how to burn more fat without more effort,

0:01:42 > 0:01:45how to tone up your body without hitting the gym.

0:01:45 > 0:01:48You can make it harder by going slower.

0:01:50 > 0:01:53We'll discover what detoxing really does to you,

0:01:53 > 0:01:58which festive leftovers you shouldn't reheat,

0:01:58 > 0:02:02and a blind woman sees in the New Year thanks to a bionic eye.

0:02:02 > 0:02:03Oh, my God!

0:02:05 > 0:02:07But first...

0:02:07 > 0:02:11As a medical journalist, I'm well aware of the benefits of exercise.

0:02:11 > 0:02:14But I also know that most people do not come remotely close to

0:02:14 > 0:02:16doing the recommended levels.

0:02:16 > 0:02:18So in this edition, we're going to be looking at ways to get

0:02:18 > 0:02:21the maximum benefit with the minimum effort.

0:02:24 > 0:02:27At this time of year, the get-fit message is everywhere.

0:02:29 > 0:02:32Along with lots of things that supposedly help.

0:02:37 > 0:02:41So Dr Chris van Tulleken has been tracking down the truth

0:02:41 > 0:02:44behind one of the most popular fitness products out

0:02:44 > 0:02:45there on the market.

0:02:47 > 0:02:50A lot of people use a protein supplement drink.

0:02:50 > 0:02:53Those drinks are made of this stuff.

0:02:53 > 0:02:56This is protein powder.

0:02:56 > 0:03:00Protein supplements became popular in California in the '70s and '80s.

0:03:01 > 0:03:04Once the preserve of giant bodybuilders,

0:03:04 > 0:03:06today they're sold to everyone

0:03:06 > 0:03:11to keep protein levels up and avoid muscle wastage as we grow older.

0:03:11 > 0:03:13And the marketing is working.

0:03:13 > 0:03:16Today, it's a £7 billion industry worldwide,

0:03:16 > 0:03:20with one in 20 taking them in late-middle age.

0:03:20 > 0:03:23But are we all being conned out of our money?

0:03:23 > 0:03:26Do you actually need more protein in your diet?

0:03:26 > 0:03:29To find out, I've come to Glasgow

0:03:29 > 0:03:32to put protein supplements to the test.

0:03:34 > 0:03:37The tempting theory behind supplements is that the protein

0:03:37 > 0:03:40in them goes straight into your muscles,

0:03:40 > 0:03:42keeping all of us in youthful vigour.

0:03:42 > 0:03:46All this is based on the idea that powders like this provide

0:03:46 > 0:03:50protein in a form that your muscles find easy to use, but is that true?

0:03:53 > 0:03:55Time for me to put in some effort

0:03:55 > 0:03:58under the supervision of Dr Stuart Gray.

0:03:58 > 0:04:03That is the proper burn. That is the full leg on fire.

0:04:03 > 0:04:05Keep it going. Keep pushing.

0:04:06 > 0:04:09I'm done. I'm done.

0:04:09 > 0:04:10Thanks, Stu.

0:04:10 > 0:04:13So now I'm going to drink a supplement drink

0:04:13 > 0:04:16and if what the manufacturers claim is true,

0:04:16 > 0:04:18then the protein from the drink is going to go

0:04:18 > 0:04:21straight into my muscle and this protein drink has a twist

0:04:21 > 0:04:24because the proteins in it are labelled chemically,

0:04:24 > 0:04:28so we can trace them as they go from my mouth to the muscle. Right.

0:04:28 > 0:04:30Just drink this?

0:04:36 > 0:04:38To trace the proteins from the drink,

0:04:38 > 0:04:43we actually need to look inside my leg muscles.

0:04:43 > 0:04:46Look away now if you're squeamish.

0:04:46 > 0:04:48Oh, my Lordy!

0:04:48 > 0:04:50Because unfortunately for me,

0:04:50 > 0:04:54that means a very large needle to take a sample from deep in my leg.

0:04:55 > 0:04:57I've only exercised one leg,

0:04:57 > 0:05:02so Stuart's taking a sample from the other leg, too, as a control.

0:05:03 > 0:05:04Then he can compare the two.

0:05:04 > 0:05:08Do proteins from supplements actually go into our muscles at all?

0:05:08 > 0:05:13And if so, does it happen more when we're exercising?

0:05:13 > 0:05:16- Was it worth it? Did you get a result?- We did, yes.

0:05:16 > 0:05:18What we saw was because we had labelled the protein that

0:05:18 > 0:05:22was in the drink, we could trace its movement through the body.

0:05:22 > 0:05:26So we saw it going into the muscle samples that we took from your legs.

0:05:26 > 0:05:28Really? That's quite surprising to me.

0:05:28 > 0:05:30Relatively quickly, as well.

0:05:30 > 0:05:33Because we only... Two or three hours we took the biopsy samples.

0:05:33 > 0:05:36It can quite quickly get into your muscle, yeah.

0:05:36 > 0:05:40And the key question, I guess, is did more of it end up in this

0:05:40 > 0:05:45leg which I exercised than in the other leg, which I didn't?

0:05:45 > 0:05:50It did, yes. So we had about 13% more of the labelled protein going

0:05:50 > 0:05:53into the exercised leg compared to your leg that you'd rested.

0:05:53 > 0:05:59Why does this muscle, when it has been exercised, need more protein?

0:05:59 > 0:06:01I'm sure, as you felt, when you exercised that muscle,

0:06:01 > 0:06:06it was painful. It was tired. So you caused slight damage to that muscle.

0:06:06 > 0:06:09It's all part of the process of building new muscle,

0:06:09 > 0:06:12so you slightly damage it and it is then repaired and it becomes...

0:06:12 > 0:06:14It is repaired bigger and stronger.

0:06:14 > 0:06:15I think that's really surprising.

0:06:15 > 0:06:17It's almost like Popeye, isn't it?

0:06:17 > 0:06:21You know, I eat the thing and then my muscles get bigger.

0:06:23 > 0:06:27So at first glance, there seems to be an unquestionable logic.

0:06:27 > 0:06:30The proteins go straight from the drink into our muscles, so they

0:06:30 > 0:06:35must be getting a boost, but for me that's not the end of the story.

0:06:35 > 0:06:37At Trust Me, I'm A Doctor, we're

0:06:37 > 0:06:42deeply suspicious of any claims of unquestionable scientific logic.

0:06:42 > 0:06:46So we're going to put protein supplements to the test.

0:06:46 > 0:06:49Do they really give you bigger, stronger muscles?

0:06:52 > 0:06:54Find out later in the programme,

0:06:54 > 0:06:57when we'll be doing a proper trial to find out once and for all.

0:07:09 > 0:07:13Exercise is something we hear a lot of at this time of year.

0:07:13 > 0:07:17We're told we should do at least 150 minutes of exercise a week.

0:07:17 > 0:07:20On top of that, the NHS recommends doing a couple of sessions

0:07:20 > 0:07:26of resistance exercise a week to build and maintain strength.

0:07:26 > 0:07:29Resistance exercises improve muscular fitness.

0:07:29 > 0:07:32But they have limited appeal.

0:07:32 > 0:07:35Do you fancy some weight training? A little bit of weights?

0:07:35 > 0:07:37Do you fancy some weight training?

0:07:37 > 0:07:39Weights? No.

0:07:43 > 0:07:47I think most people find the idea of pumping iron rather intimidating.

0:07:47 > 0:07:52Plus not that many people actually want bulging biceps, so how can

0:07:52 > 0:07:57you get the benefits of resistance exercise without going down the gym?

0:07:57 > 0:08:00The benefits we are after have nothing to do with a washboard

0:08:00 > 0:08:03stomach or a sixpack.

0:08:03 > 0:08:07Sadly, as we enter our 40s, our bodies get worse at building

0:08:07 > 0:08:09and maintaining muscle.

0:08:09 > 0:08:12So as we get older, we get weaker.

0:08:12 > 0:08:14But how bad does it get?

0:08:14 > 0:08:18At the University of Nottingham, Dr Philip Atherton is going to

0:08:18 > 0:08:22take a peek inside my 58-year-old thigh.

0:08:22 > 0:08:24- If I move around a bit? - If you contract there, you can

0:08:24 > 0:08:28actually see that the muscle fibre angles sort of change and tip

0:08:28 > 0:08:31and that is the sort of contraction of the muscle.

0:08:31 > 0:08:34That's cool. I've never seen that before.

0:08:34 > 0:08:36So if I don't do anything much with

0:08:36 > 0:08:40it from my age now, that' just going to get smaller, is it?

0:08:40 > 0:08:45- Essentially, given that you're 50 now, Michael...- 50+.- 50+, OK.

0:08:45 > 0:08:49..you would be expecting in essence to lose around 5% on average

0:08:49 > 0:08:51of muscle mass per decade. It could even exceed that.

0:08:51 > 0:08:53This is the time at which muscle really,

0:08:53 > 0:08:57really starts to decline in mass, so what we would expect to see is

0:08:57 > 0:09:00if we were to measure this decade by decade, we would probably see

0:09:00 > 0:09:04that that muscle would get thinner and thinner over time.

0:09:04 > 0:09:05From the age of 40,

0:09:05 > 0:09:09we can lose up to 1% of our muscle mass every single year.

0:09:09 > 0:09:13And that loss affects more than just our strength.

0:09:13 > 0:09:15If you look in very, very large-scale studies,

0:09:15 > 0:09:21one of the best predictors of poor health in older age

0:09:21 > 0:09:23and even early death is actually muscle mass.

0:09:26 > 0:09:30It's all sounding rather depressing. But there is some good news.

0:09:30 > 0:09:36The right exercises can slow, even reverse, this decline in strength.

0:09:36 > 0:09:38But do you have to hit the gym to do it?

0:09:38 > 0:09:41Or is there an easier way?

0:09:42 > 0:09:46With a group of intrepid volunteers, we're going to find out.

0:09:47 > 0:09:51They're all the wrong side of 40 and at risk of losing their muscles.

0:09:51 > 0:09:53We begin by testing their strength.

0:09:53 > 0:09:57And push, push, push, push! Keep going, keep going, keep going!

0:09:57 > 0:09:59These machines measure how strong their legs are

0:09:59 > 0:10:02and how much power they can release in one go.

0:10:04 > 0:10:08Ultrasound tells us how big their thigh muscles are.

0:10:08 > 0:10:11And we're also testing their grip strength.

0:10:11 > 0:10:13Together, these readings give us

0:10:13 > 0:10:16a good indication of whole body strength.

0:10:16 > 0:10:20And now, we're ready to see if we can turn back time

0:10:20 > 0:10:24and build muscle without any special equipment.

0:10:26 > 0:10:29Our volunteers have been given a set of exercises

0:10:29 > 0:10:33which are designed to fit in seamlessly with their domestic lives.

0:10:33 > 0:10:36Let me demonstrate.

0:10:36 > 0:10:39These are bicep curls with ordinary sort of household items -

0:10:39 > 0:10:41in this case, bags of flour.

0:10:43 > 0:10:46This is a classic exercise, the lunge.

0:10:46 > 0:10:49Except it's done while you're vacuuming.

0:10:54 > 0:10:57This is a toothbrush squat.

0:10:57 > 0:11:01The idea is that you're working some of the biggest muscles in the body,

0:11:01 > 0:11:05those in your bottom, and you can make it harder by going slower

0:11:05 > 0:11:07and obviously by doing more.

0:11:10 > 0:11:15Our volunteers carry out a set of eight exercises every day,

0:11:15 > 0:11:18working muscles all over their bodies.

0:11:19 > 0:11:22But will this DIY approach to resistance training really

0:11:22 > 0:11:25make a difference?

0:11:31 > 0:11:34With a month up, it's time to find out.

0:11:34 > 0:11:38We measure their strength and thigh muscle thickness again.

0:11:38 > 0:11:42And the results have certainly surprised muscle expert

0:11:42 > 0:11:44Dr Philip Atherton.

0:11:44 > 0:11:46OK. So, moment of truth.

0:11:46 > 0:11:48Whether those four weeks have actually been worth doing.

0:11:48 > 0:11:51I'm very intrigued. Where are we, then?

0:11:51 > 0:11:54So what we found with the group is basically there was a 3%

0:11:54 > 0:11:57increase in the cross-sectional area of the leg muscles.

0:11:57 > 0:12:00OK. 3%? Yeah, yeah.

0:12:00 > 0:12:02They haven't started to look like bodybuilders,

0:12:02 > 0:12:04and they're more toned.

0:12:04 > 0:12:07But have they become stronger, the important measure?

0:12:07 > 0:12:10We looked at leg strength and we were able to detect an increase,

0:12:10 > 0:12:13and, again on a group basis, this was about 12%.

0:12:13 > 0:12:16Ooh, yeah. We like that.

0:12:16 > 0:12:18- 12% is a big number. - Yeah, absolutely.

0:12:18 > 0:12:21This is again a marked increase in leg strength

0:12:21 > 0:12:22and following that as well...

0:12:22 > 0:12:24Do you think that was the squats?

0:12:24 > 0:12:27I think it could have been very much part of the reason why

0:12:27 > 0:12:28their strength increased.

0:12:28 > 0:12:31But interestingly, the power increase is similar to the muscle

0:12:31 > 0:12:34strength in that it increased 13% as a group.

0:12:34 > 0:12:36Wa-hey! So you're all dynamos.

0:12:36 > 0:12:41Can you feel that energy just surging through you now, that power?

0:12:41 > 0:12:45So a 3% increase in the area of the muscle led to a 12%

0:12:45 > 0:12:48increase in muscle strength,

0:12:48 > 0:12:51and a 13% increase in power output.

0:12:51 > 0:12:56And their grip strength also increased by 4%.

0:12:56 > 0:12:57I think that's quite incredible.

0:12:57 > 0:13:02Proof that our home training programme has really worked.

0:13:02 > 0:13:04I must admit, I am astonished that in four weeks you can see such

0:13:04 > 0:13:07big changes, particularly in things like power.

0:13:07 > 0:13:10I understand the other ones kind of matter, but that is big.

0:13:10 > 0:13:12Did you find it OK?

0:13:12 > 0:13:14Yes. Yes, you could incorporate it into your daily routine.

0:13:14 > 0:13:16Do you think you will continue?

0:13:16 > 0:13:17Yes. Certainly will do.

0:13:17 > 0:13:19Especially with the results.

0:13:19 > 0:13:22The results of these no-sweat exercises have

0:13:22 > 0:13:24delighted our volunteers.

0:13:24 > 0:13:27I do feel stronger.

0:13:27 > 0:13:30I do feel fitter after the programme,

0:13:30 > 0:13:31and I intend to keep it on.

0:13:34 > 0:13:38They are now stronger, fitter, and more resilient.

0:13:38 > 0:13:43And all our exercises can be done for free in the privacy of your own home.

0:13:43 > 0:13:46They can even be done while you're watching the telly.

0:13:46 > 0:13:48There is a full list of the exercises

0:13:48 > 0:13:51and the proper instructions on our Trust Me website.

0:14:00 > 0:14:04And now surgeon Gabriel Weston is in the New Year spirit.

0:14:05 > 0:14:09And what better way to start off a January health kick than with

0:14:09 > 0:14:12juices and smoothies?

0:14:12 > 0:14:15The biggest claim they make is that they're full of antioxidants.

0:14:15 > 0:14:19But does that really mean they're good for us?

0:14:19 > 0:14:24The message written on the side of this carton feels very clear.

0:14:24 > 0:14:27Oxidation causes damage to your cells and that if you

0:14:27 > 0:14:32drink lots of this antioxidant juice, it will protect them.

0:14:32 > 0:14:34But is that actually true?

0:14:35 > 0:14:40Antioxidants are meant to mop up free radicals,

0:14:40 > 0:14:43byproducts of chemical reactions in our cells.

0:14:43 > 0:14:46Now, for many years, free radicals have been thought to cause

0:14:46 > 0:14:49an accumulation of damage to cells,

0:14:49 > 0:14:52possibly even reducing our lifespan.

0:14:52 > 0:14:57So taking extra antioxidants should help combat this.

0:14:57 > 0:15:00But does it?

0:15:00 > 0:15:02We want to test whether juices

0:15:02 > 0:15:05and smoothies really do live up to the hype.

0:15:05 > 0:15:09So first, just how powerful is their antioxidant kick?

0:15:11 > 0:15:14Newcastle University are analysing some for us,

0:15:14 > 0:15:18and comparing them with some bog-standard orange juices.

0:15:18 > 0:15:20And the results are surprising.

0:15:23 > 0:15:26First up, the orange juices.

0:15:26 > 0:15:30Then, a fresh super-fruit smoothie - twice the price,

0:15:30 > 0:15:33but no more antioxidants.

0:15:33 > 0:15:36Next, two brands of smoothies specifically

0:15:36 > 0:15:38marketed for antioxidants.

0:15:38 > 0:15:41Still no better.

0:15:41 > 0:15:45Finally, a superfood smoothie, a whopping three times

0:15:45 > 0:15:49the antioxidant power of any of the others.

0:15:49 > 0:15:51So what's going on?

0:15:53 > 0:15:57Antioxidants might have an air of mystery about them, but if you look

0:15:57 > 0:16:01at the label on the side of one of these drinks, it's clear that most

0:16:01 > 0:16:07of the antioxidant effect is just coming from plain old vitamin C.

0:16:08 > 0:16:11Vitamin C is actually a powerful antioxidant.

0:16:11 > 0:16:14It's found naturally in most fruit and veg,

0:16:14 > 0:16:18but is also a common additive to stop juice going brown.

0:16:18 > 0:16:22There's nothing special about fruits themselves in these drinks.

0:16:22 > 0:16:27So my next question is, do the antioxidants in these drinks

0:16:27 > 0:16:30actually do anything inside our bodies?

0:16:32 > 0:16:34To find out,

0:16:34 > 0:16:38we recruited ten volunteers to do an experiment never attempted before.

0:16:38 > 0:16:41Under the guidance of Dr Kirsten Grant,

0:16:41 > 0:16:45they all drank 360ml of smoothie.

0:16:45 > 0:16:49We measured the antioxidant status of each person's blood

0:16:49 > 0:16:51beforehand so we had a baseline,

0:16:51 > 0:16:54and then regularly over the next 24 hours.

0:16:56 > 0:16:59Did the smoothie give them an antioxidant boost?

0:16:59 > 0:17:03Well, at first, the antioxidant levels in their blood did go up,

0:17:03 > 0:17:07only to plummet dramatically after 4-5 hours.

0:17:07 > 0:17:10And they even went well below baseline

0:17:10 > 0:17:15and were only just coming back to baseline after 24 hours.

0:17:15 > 0:17:18Kirsten was not surprised by the sudden drop to below baseline,

0:17:18 > 0:17:22as our bodies actually work to keep everything in perfect balance,

0:17:22 > 0:17:26including antioxidant levels.

0:17:26 > 0:17:30This balance where the body will keep the level constant,

0:17:30 > 0:17:34it's called homeostasis, and it's the same for our temperature,

0:17:34 > 0:17:35for our sugar levels,

0:17:35 > 0:17:39for everything else in the body that should have a correct level.

0:17:39 > 0:17:43Our bodies continually produce their own antioxidants.

0:17:43 > 0:17:45When we take in a big extra dose,

0:17:45 > 0:17:49our bodies slow down that production to get back to the optimum level.

0:17:49 > 0:17:53But what Kirsten had not expected was that it would take so long.

0:17:53 > 0:17:58For almost a day after drinking just a big glass of smoothie of juice,

0:17:58 > 0:18:03our volunteers' blood contained less antioxidant power than normal.

0:18:03 > 0:18:06It's the opposite effect from what most of us would expect.

0:18:06 > 0:18:10And lower antioxidant levels presumably mean more free

0:18:10 > 0:18:12radicals in our bodies.

0:18:12 > 0:18:16But Kirsten thinks the messages we get from the adverts are even

0:18:16 > 0:18:17more misleading,

0:18:17 > 0:18:20as free radicals are not such a bad thing.

0:18:21 > 0:18:25So it isn't the case that all of us have got our bodies

0:18:25 > 0:18:29full of bad free radicals and the more we slosh the smoothie in,

0:18:29 > 0:18:33the more they're going to mop up those bad things in our body?

0:18:33 > 0:18:35No. Normal, healthy people have

0:18:35 > 0:18:37exactly the free radicals that they need.

0:18:37 > 0:18:40Free radicals are actually quite important.

0:18:40 > 0:18:43For example, they are one of the signal molecules that tells the

0:18:43 > 0:18:47cells in our body when you need to repair, for example, muscle fibres.

0:18:47 > 0:18:50So if you want to go to the gym and do some training,

0:18:50 > 0:18:54if it wasn't for the free radicals, your muscles wouldn't grow.

0:18:55 > 0:18:59The science and the marketing are poles apart.

0:18:59 > 0:19:02Your body makes exactly the antioxidants it needs

0:19:02 > 0:19:06and taking in a big dose merely throws it out of balance.

0:19:08 > 0:19:11While there's excellent evidence that eating fruit and vegetables

0:19:11 > 0:19:16is good for you, the benefit isn't coming from the antioxidants.

0:19:16 > 0:19:20So ignore the marketing hype, banish the detox myth,

0:19:20 > 0:19:25and stop wasting your money on all those fancy smoothies and juices.

0:19:25 > 0:19:28We contacted two leading smoothie manufacturers, who said their

0:19:28 > 0:19:31products were a convenient way of getting more fruits

0:19:31 > 0:19:33and vegetables at a time when only a third of the UK

0:19:33 > 0:19:35population are getting their five a day.

0:19:35 > 0:19:37They're confident that the vitamins

0:19:37 > 0:19:40and minerals in their antioxidant recipes contribute to

0:19:40 > 0:19:42the protection of cells from oxidative stress,

0:19:42 > 0:19:45a claim that is supported by specific European regulations.

0:19:45 > 0:19:48Their statements are published in full on our website.

0:19:56 > 0:20:00Now, for most people, the point of doing exercise is to burn excess fat.

0:20:00 > 0:20:04But what if you could do that without any extra effort at all?

0:20:04 > 0:20:07Well, we've decided to take some tantalising new research

0:20:07 > 0:20:11out of the lab and put it to a real test for the very first time.

0:20:11 > 0:20:14Over to Dr Saleyha Ahsan.

0:20:20 > 0:20:22For most of us,

0:20:22 > 0:20:25losing the spare tyre can be a bit of an uphill struggle.

0:20:27 > 0:20:30But is there a smarter way of turning our bodies into more

0:20:30 > 0:20:33efficient fat-burning machines,

0:20:33 > 0:20:37not by exercising more, but by changing the time that we do it?

0:20:39 > 0:20:42We've come across some brand-new research at the University

0:20:42 > 0:20:46of Surrey that suggests to burn more fat, you don't need to

0:20:46 > 0:20:51change your diet or how much exercise -

0:20:51 > 0:20:56the secret is knowing when to eat and when to exercise.

0:20:57 > 0:21:02First, brother and sister Josh and Jess are going to be tested

0:21:02 > 0:21:06under lab conditions as they exercise on an empty stomach.

0:21:06 > 0:21:09Neither has eaten since yesterday evening.

0:21:09 > 0:21:11So are you hungry?

0:21:11 > 0:21:14- Starving.- Ravenous.

0:21:15 > 0:21:19But before they eat, they'll do half an hour of exercise and

0:21:19 > 0:21:24Dr Adam Collins is going to measure how much fat their bodies burn.

0:21:24 > 0:21:26And you're off.

0:21:28 > 0:21:30This looks a bit complicated.

0:21:30 > 0:21:33Well, what we're monitoring here is the fuels that are

0:21:33 > 0:21:37burning during exercise, so when you're exercising, you

0:21:37 > 0:21:42are using a combination of glucose, which is a carbohydrate, or fat.

0:21:42 > 0:21:44You can see, he's got a face mask there

0:21:44 > 0:21:47and we're sampling the air that he's breathing in and out.

0:21:47 > 0:21:50In particular, we're looking at the oxygen that he's breathing in

0:21:50 > 0:21:52and the amount of carbon dioxide he's breathing out.

0:21:52 > 0:21:56And with those two things, we can work out how much fat he's

0:21:56 > 0:21:58burning and how much carbohydrate he's burning.

0:22:00 > 0:22:02So our body uses two different types of fuel.

0:22:02 > 0:22:05Carbohydrate and fat.

0:22:05 > 0:22:08And what we're interested in is the fat burn,

0:22:08 > 0:22:12because that's what's key to losing the spare tyre.

0:22:12 > 0:22:16Today, we're measuring how much fat Josh is burning

0:22:16 > 0:22:20when he exercises before he eats.

0:22:20 > 0:22:21Josh, how are you doing?

0:22:21 > 0:22:24- I'm alive.- You're alive.

0:22:24 > 0:22:26He's still talking, which is good.

0:22:30 > 0:22:33After 30 minutes, it's Jess' turn to jump on the bike.

0:22:36 > 0:22:38But Josh isn't finished.

0:22:40 > 0:22:43So what we're interested in is the impact of exercise after

0:22:43 > 0:22:45the exercise is finished.

0:22:45 > 0:22:48Because that's when you do most of your fat burning,

0:22:48 > 0:22:51so most of the effect of that exercise actually

0:22:51 > 0:22:55happens in the period after the exercise rather than during it.

0:22:55 > 0:22:58- Tuck in. Breakfast.- Thank you.

0:22:58 > 0:23:00Now, Josh gets some breakfast.

0:23:00 > 0:23:03It's in the form of a drink

0:23:03 > 0:23:06so that the calories can be precisely controlled.

0:23:06 > 0:23:10Meal over, Adam continues to measure how much fat Josh is

0:23:10 > 0:23:13burning now that he is no longer exercising.

0:23:13 > 0:23:15So that doesn't look very relaxing.

0:23:15 > 0:23:17It's good.

0:23:17 > 0:23:19- It's very calming underneath there. - OK.

0:23:22 > 0:23:25And 30 minutes later, with her exercise complete,

0:23:25 > 0:23:28it's Jess' turn for breakfast.

0:23:28 > 0:23:31Now, she too will have the amount of fat she's burning

0:23:31 > 0:23:36measured for the next three hours, when she's not exercising.

0:23:37 > 0:23:39But this isn't the first time that they've

0:23:39 > 0:23:42undergone a test like this.

0:23:45 > 0:23:49One week ago, Josh and Jess did almost the same thing,

0:23:49 > 0:23:54except then they exercised after they'd had the liquid meal.

0:23:56 > 0:24:00So now we should be able to see whether exercising before or

0:24:00 > 0:24:04after eating is better for making your body burn fat.

0:24:07 > 0:24:09And the results are astonishing.

0:24:09 > 0:24:16Josh burned 10% more fat after he exercised on an empty stomach.

0:24:16 > 0:24:19But for Jess, it was the reverse.

0:24:19 > 0:24:23She burned more fat after she exercised on a full stomach.

0:24:25 > 0:24:29Remarkably, it seems the secret of how to burn more fat might be

0:24:29 > 0:24:31different for men and women.

0:24:31 > 0:24:34It's an exciting new idea that has only

0:24:34 > 0:24:39so far been seen in these carefully controlled laboratory conditions.

0:24:39 > 0:24:41This is just one bout of exercise.

0:24:41 > 0:24:43But people do repeated bouts of exercise.

0:24:43 > 0:24:45They go to the gym on a regular basis

0:24:45 > 0:24:48or they exercise several times a week.

0:24:48 > 0:24:50This could have a cumulative effect

0:24:50 > 0:24:53in terms of maximising your fat burning.

0:24:54 > 0:24:57So we've teamed up with Adam to test his discovery in the real

0:24:57 > 0:24:59world for the first time.

0:24:59 > 0:25:05We want to find out if men and women really do burn fat differently.

0:25:05 > 0:25:07Should men be exercising on an empty stomach

0:25:07 > 0:25:10and women after they've eaten?

0:25:10 > 0:25:12We'll find out later in the programme.

0:25:22 > 0:25:24Still to come -

0:25:24 > 0:25:26could having a big bum be good for you?

0:25:26 > 0:25:28And allowing the blind to see again.

0:25:28 > 0:25:31Honest to God, I felt like Christmas Day there!

0:25:31 > 0:25:33But first...

0:25:41 > 0:25:44..we're all keen to impress the friends and family we have

0:25:44 > 0:25:47round during the festive season,

0:25:47 > 0:25:50but with big meals come leftovers aplenty.

0:25:50 > 0:25:54And not reheating them properly contributes to an impressive

0:25:54 > 0:25:57surge in food poisonings at this time of year.

0:25:58 > 0:26:00So how can we all avoid it?

0:26:03 > 0:26:08Now, food shows don't normally deal with the subject of food poisoning.

0:26:08 > 0:26:11But they've kindly allowed us to gatecrash their demonstration.

0:26:11 > 0:26:14Hi, there. Good evening. Thank you for coming.

0:26:14 > 0:26:17Are you having a good day? Good.

0:26:17 > 0:26:20We all know we have to cook raw meat thoroughly,

0:26:20 > 0:26:22but what are the rules for leftovers?

0:26:22 > 0:26:26- Right. I have here a delicious curry I made a couple of days ago.- OK.

0:26:26 > 0:26:28Would you be happy to reheat it and eat it?

0:26:28 > 0:26:31I'll pass on that one, then. Thank you.

0:26:31 > 0:26:34So is it OK to be reheat it?

0:26:35 > 0:26:38You think not? You'd go straight in the bin?

0:26:38 > 0:26:42Would you happily heat it and eat it?

0:26:42 > 0:26:44- Yes.- You'd be happy?- Yeah.

0:26:45 > 0:26:51The Food Standards Agency suggest we only reheat our leftovers once.

0:26:51 > 0:26:56Although you can actually reheat your leftovers as many times as you like,

0:26:56 > 0:27:01as long as you make sure every morsel is piping hot all the way through.

0:27:01 > 0:27:06Easy enough to do on the stove, but most of us use a microwave,

0:27:06 > 0:27:09which leads to another common problem.

0:27:09 > 0:27:15Microwaves create hotspots and dangerous cool spots in your food,

0:27:15 > 0:27:18seen in red and blue on the thermal imaging camera.

0:27:18 > 0:27:22And in the cool spots, bacteria can thrive.

0:27:22 > 0:27:26So if you use a microwave, be sure to heat and stir and heat

0:27:26 > 0:27:31and stir until you're satisfied it's really hot all the way through.

0:27:31 > 0:27:34But there is one thing you should be cautious of reheating.

0:27:34 > 0:27:37Do you think it's the rice or the chicken that's more dangerous?

0:27:37 > 0:27:39- I would say the chicken.- The rice.

0:27:39 > 0:27:42- And you said rice? - You hear a lot on TV about rice.

0:27:42 > 0:27:45I think if I heated the chicken up, I'd be all right, but the rice...

0:27:45 > 0:27:47My wife tells me this all the time.

0:27:47 > 0:27:49Do not save rice under any circumstances.

0:27:49 > 0:27:54There is a bacteria called Bacillus cereus. And that lives in rice.

0:27:54 > 0:27:58And the thing about Bacillus cereus is that it also produces a toxin

0:27:58 > 0:28:01and unfortunately the toxin is heat stable.

0:28:01 > 0:28:05That means that you can heat it up, it will kill the bacteria,

0:28:05 > 0:28:07but the toxin will get you.

0:28:07 > 0:28:10So you can kill the bacteria,

0:28:10 > 0:28:13but if they've already produced the toxin, that rice is going to

0:28:13 > 0:28:17be poisonous, no matter how thoroughly you reheat it.

0:28:17 > 0:28:21So put uneaten right in the fridge as soon as it's cooled down to

0:28:21 > 0:28:24room temperature and only reheat it once.

0:28:27 > 0:28:32So the rules are you can reheat food as many times as you like

0:28:32 > 0:28:35if you heat it thoroughly all the way through.

0:28:35 > 0:28:37The exception is rice.

0:28:37 > 0:28:40Refrigerate that carefully and only reheat it once.

0:28:40 > 0:28:44Do that and you should be safe. Trust me.

0:28:44 > 0:28:46- Can't tempt you?- No.

0:28:46 > 0:28:48No, you're right. You can't.

0:28:58 > 0:29:01Earlier in the programme, I set out to discover

0:29:01 > 0:29:04whether the proteins from supplements could go straight into

0:29:04 > 0:29:07our muscles, as the manufacturers would like us to believe.

0:29:07 > 0:29:11And I was surprised to discover that they could.

0:29:11 > 0:29:14And that the amount is higher with exercise.

0:29:14 > 0:29:16But does that mean that taking

0:29:16 > 0:29:19protein supplements gives us bigger muscles?

0:29:20 > 0:29:25Well, to find out, we're going to do a big experiment of our own.

0:29:25 > 0:29:27We've recruited 24 volunteers,

0:29:27 > 0:29:31ranging in age from 20 to 67.

0:29:31 > 0:29:34They all had a set of baseline measurements taken -

0:29:34 > 0:29:36muscle strength, body fat composition,

0:29:36 > 0:29:38and an ultrasound of their muscles.

0:29:38 > 0:29:42Now, they're going to start on an eight-week training regime,

0:29:42 > 0:29:45each gym session followed by an identical-looking drink.

0:29:45 > 0:29:47But here's the twist.

0:29:47 > 0:29:50While half of our volunteers are going to get a protein shake,

0:29:50 > 0:29:53the other half are going to get a shake that appears to be

0:29:53 > 0:29:57the same, but has no protein in it whatsoever - a placebo.

0:29:59 > 0:30:02Lifting heavy weights three times a week should get their cells

0:30:02 > 0:30:06releasing free radicals, signalling their bodies to repair

0:30:06 > 0:30:08and boost their muscles.

0:30:08 > 0:30:12But will drinking a protein shake make them grow stronger and bigger?

0:30:12 > 0:30:17Even supervising scientist Dr Stuart Grey doesn't know

0:30:17 > 0:30:19who's getting which shake...

0:30:19 > 0:30:21but everyone's still happy with the regime.

0:30:21 > 0:30:24I feel like I've got stronger, but that's just with the process

0:30:24 > 0:30:27and working hard through the eight weeks.

0:30:28 > 0:30:31But eight weeks later, after they're all retested,

0:30:31 > 0:30:34- what do the results show?- Good news.

0:30:34 > 0:30:39Everyone got stronger, so you're all about on average 30% stronger

0:30:39 > 0:30:44- than you were before you started. - 30%.- 30% stronger.- You look better.

0:30:44 > 0:30:47You looked pretty ropey before, but, you know.

0:30:47 > 0:30:48And you're not only stronger,

0:30:48 > 0:30:51you do have on average 1-2% more muscle mass than you did

0:30:51 > 0:30:55when you started, so you've got bigger muscles and you're stronger.

0:30:55 > 0:30:57What more could you want?

0:30:57 > 0:30:59So the crucial question is,

0:30:59 > 0:31:04did the people who had the real protein shake get stronger

0:31:04 > 0:31:07or put on more muscle than the people who had the placebo?

0:31:07 > 0:31:10- In short, no. Unfortunately not.- Really?- No.

0:31:10 > 0:31:16No difference at all between the two groups. Everything exactly the same.

0:31:16 > 0:31:18I must say I'm a little bit disappointed by that.

0:31:18 > 0:31:21The extra that we were giving them

0:31:21 > 0:31:24wasn't really making much difference at all.

0:31:25 > 0:31:30Our results show that everyone got stronger, more able to lift weights

0:31:30 > 0:31:32and everyone put on more muscle,

0:31:32 > 0:31:34but there was no significant difference

0:31:34 > 0:31:36between those that were given the protein supplements

0:31:36 > 0:31:39and those that got placebo.

0:31:39 > 0:31:41So, over our eight-week trial,

0:31:41 > 0:31:46the protein shakes did not give them a benefit. This seems baffling.

0:31:46 > 0:31:50After all, earlier in the programme, I saw first-hand how protein

0:31:50 > 0:31:55I'd consumed in a shake went directly into my leg after exercise.

0:31:55 > 0:31:58But, as Stuart explains, our diets are full of protein

0:31:58 > 0:32:02and adding extra doesn't seem to help us build muscle.

0:32:02 > 0:32:04There's a limit to what the body can cope with.

0:32:04 > 0:32:08About 20 to 30 grams is as much as your body can take in,

0:32:08 > 0:32:09in a single consumption.

0:32:09 > 0:32:13Anything more, you're really going to burn it as energy,

0:32:13 > 0:32:16oxidise it, you're going to store it as, most likely, fat

0:32:16 > 0:32:18or you're just going to pee it out in the urine,

0:32:18 > 0:32:20so it's not going to get into the muscle.

0:32:20 > 0:32:23So once you've got enough protein on board, basically,

0:32:23 > 0:32:29- anything else is turned into urine, fat or energy.- Yeah, yeah.

0:32:29 > 0:32:31So, it's not going to do what you want it to do.

0:32:31 > 0:32:35Who's going to go and buy a fancy protein drink and take it?

0:32:36 > 0:32:38- You're still going to do it. - Get out!

0:32:39 > 0:32:42- There's always one. - Very nice, very nice.

0:32:42 > 0:32:46So whilst protein from supplements can go directly into your muscles,

0:32:46 > 0:32:50taking them isn't actually going to help you build any more muscle

0:32:50 > 0:32:54because as long as we get enough protein in our normal diet,

0:32:54 > 0:32:55any extra is just a waste.

0:32:57 > 0:33:01The truth is, that none of us need to drink these protein supplements.

0:33:01 > 0:33:03If you're getting extra protein in that way,

0:33:03 > 0:33:06you're probably just making very expensive urine,

0:33:06 > 0:33:08so if I were you I'd cut out the middleman.

0:33:22 > 0:33:26Protein shakes aren't the only drinks designed for gym bunnies

0:33:26 > 0:33:29that made their way onto supermarket shelves.

0:33:29 > 0:33:32Energy drinks are big business.

0:33:32 > 0:33:36We get through about 45 million litres of the stuff every year.

0:33:36 > 0:33:40Now, they claim to keep you energised and rehydrated,

0:33:40 > 0:33:41so what's actually in them?

0:33:43 > 0:33:45And are they worth the money?

0:33:45 > 0:33:49I'm going to show you how easy it is to make your own, virtually for free.

0:33:49 > 0:33:52The first and most obvious thing you need is water.

0:33:52 > 0:33:56Here is about half a litre of ordinary tap water.

0:33:56 > 0:34:00That's about the same amount as you'd find in one of these bottles.

0:34:00 > 0:34:04The next magic ingredient is sugar and each of these contains

0:34:04 > 0:34:08the equivalent of six to eight teaspoons of sugar.

0:34:11 > 0:34:13And because that tastes pretty unpleasant,

0:34:13 > 0:34:16I think I'll add a little splash of orange squash.

0:34:19 > 0:34:23If you are really working hard and sweating like crazy,

0:34:23 > 0:34:26then you are going to be losing electrolytes

0:34:26 > 0:34:28and how do you replace them?

0:34:28 > 0:34:32Well, you can do so with about an eighth of a teaspoon of this stuff,

0:34:32 > 0:34:36which is sodium chloride, also known as salt.

0:34:39 > 0:34:40And there you have it.

0:34:40 > 0:34:45Michael Mosley's sports drink, made out of sugar, water,

0:34:45 > 0:34:50salt and just a hint of flavouring. Costs virtually nothing.

0:34:50 > 0:34:52The only remaining question is

0:34:52 > 0:34:55should I drink it before or after exercising?

0:35:05 > 0:35:08Earlier in the programme, we discovered that the secret

0:35:08 > 0:35:12of how to burn more fat might be different for men and women.

0:35:12 > 0:35:16Our laboratory test on a brother and sister pair suggested that

0:35:16 > 0:35:21men burn more fat after they've exercised on an empty stomach,

0:35:21 > 0:35:22women on a full stomach.

0:35:24 > 0:35:26It's a new discovery

0:35:26 > 0:35:30and it's never been tested in the real world until now.

0:35:34 > 0:35:37We've recruited a group of 31 volunteers.

0:35:37 > 0:35:40They're about to embark on a four-week experiment.

0:35:41 > 0:35:45Before they start, Adam Collins is taking a baseline measurement

0:35:45 > 0:35:49of how much fat their bodies are burning when they're at rest.

0:35:50 > 0:35:53Now it's time to split them into two groups.

0:35:53 > 0:35:56Both will be given an identical breakfast -

0:35:56 > 0:36:00a special drink with a precisely controlled number of calories.

0:36:02 > 0:36:05Group 1 will have theirs before they exercise.

0:36:05 > 0:36:08Group 2 will have theirs after they exercise.

0:36:08 > 0:36:12Both groups will do exactly the same exercise programme -

0:36:12 > 0:36:15a combination of high-intensity training,

0:36:15 > 0:36:20Zumba, and spin classes, carried out first thing in the morning.

0:36:21 > 0:36:25We want to test the idea that men can burn more fat

0:36:25 > 0:36:30if they exercise on an empty stomach, women on a full stomach.

0:36:30 > 0:36:34After four weeks of exercise, we'll take the same measurements again

0:36:34 > 0:36:38to see if there's been any change in how much fat they're burning.

0:36:38 > 0:36:44We want to see if shifting exercise to before or after eating

0:36:44 > 0:36:46will have any effect in the longer term.

0:36:48 > 0:36:50Find out later in the programme.

0:37:00 > 0:37:02There are some medical inventions which, to me,

0:37:02 > 0:37:07still feel like science fiction - the bionic eye, for example.

0:37:07 > 0:37:10Well, surgeon Gabriel Weston has been following the story

0:37:10 > 0:37:12of a woman who is about to have one

0:37:12 > 0:37:15of the world's most advanced artificial eyes.

0:37:19 > 0:37:22When she was just five years old,

0:37:22 > 0:37:26Rhian Lewis was diagnosed with retinitis pigmentosa...

0:37:27 > 0:37:31..a disease that damages the light-sensitive cells in the retina.

0:37:33 > 0:37:36Her right eye is now completely blind...

0:37:37 > 0:37:41..and her left eye is virtually without sight.

0:37:41 > 0:37:44It's a bit like if somebody's putting a dimmer switch off

0:37:44 > 0:37:47ever so gradually and the dimmer switch is going lower and lower

0:37:47 > 0:37:50and lower and the light is going less and less.

0:37:50 > 0:37:54It's been maybe eight years since I've had any idea

0:37:54 > 0:37:58what my children look like and I certainly don't know how I've aged.

0:38:03 > 0:38:05There is no cure for this disease,

0:38:05 > 0:38:07but a treatment being trialled in Oxford

0:38:07 > 0:38:10could give Rhian back some of her sight.

0:38:11 > 0:38:14Surgeons are going to replace the damaged retinal cells

0:38:14 > 0:38:16with an electronic chip.

0:38:17 > 0:38:19If I had a little bit more sight,

0:38:19 > 0:38:22I'd have a little bit more confidence and I might venture out.

0:38:22 > 0:38:23That's my big thing.

0:38:24 > 0:38:28Rhian is about to become the very first patient

0:38:28 > 0:38:30in an NHS-funded trial

0:38:30 > 0:38:34which is looking at the most advanced kind of retinal implant -

0:38:34 > 0:38:36something that most people are beginning to know

0:38:36 > 0:38:41as the bionic eye - and if it works, it could restore elements

0:38:41 > 0:38:46of her vision that she thought that she had completely lost for ever.

0:38:49 > 0:38:54The implant has been developed in Germany and the delicate task

0:38:54 > 0:38:59of positioning it will fall to Professor Robert MacLaren.

0:38:59 > 0:39:01We've got to get the implant in exactly the right position

0:39:01 > 0:39:05at the back of the eye, but we also need to avoid damaging the nerve.

0:39:05 > 0:39:07We need the nerve to send the signals from the implant

0:39:07 > 0:39:09back into the brain

0:39:09 > 0:39:12and that nerve is less than a millimetre from the optimal position

0:39:12 > 0:39:14of the chip and if we move the chip a millimetre the other way,

0:39:14 > 0:39:16we may not get very useful vision.

0:39:16 > 0:39:19So it is absolutely critical and that's what takes a long time -

0:39:19 > 0:39:20it's getting that position exactly right.

0:39:22 > 0:39:26This entire process will take about ten hours.

0:39:27 > 0:39:30Already the ENT surgeon has implanted a power supply

0:39:30 > 0:39:32for the device behind Rhian's ear.

0:39:33 > 0:39:36Now, Robert and his assistant, Tom Edwards,

0:39:36 > 0:39:40can begin the intricate job of inserting the chip.

0:39:43 > 0:39:48The chip is only three millimetres wide and the delicacy required

0:39:48 > 0:39:52to manoeuvre it into place is extraordinary.

0:39:55 > 0:39:57This is a very tense moment in the surgery.

0:39:57 > 0:40:00The guide wire has been removed,

0:40:00 > 0:40:05leaving the implant exactly where it needs to be, and Tom's holding it

0:40:05 > 0:40:09there, absolutely still, so Robert can fix it in place.

0:40:12 > 0:40:15Brain surgeons are always given all the credit

0:40:15 > 0:40:18for doing the most delicate, difficult work

0:40:18 > 0:40:20and, to my mind, these guys are absolutely up there.

0:40:30 > 0:40:34The operation has gone well, but it's only a few weeks later -

0:40:34 > 0:40:36when Rhian's eye has healed -

0:40:36 > 0:40:39that she'll know whether the implant works.

0:40:40 > 0:40:45It's a big moment, not just for her, but for the whole team.

0:40:47 > 0:40:50- Yes, there is a pulse rather than a flash.- Uh-huh?

0:40:50 > 0:40:53- So shall I go down a bit further? - You can.

0:40:53 > 0:40:57At first, Rhian will only be able to see flashes of light.

0:40:57 > 0:41:01That's because her brain has to learn how to see again.

0:41:02 > 0:41:05What Rhian and others are trying to do is to reactivate

0:41:05 > 0:41:08part of the brain that hasn't been doing anything

0:41:08 > 0:41:09for the last ten years or so,

0:41:09 > 0:41:12and it's almost like a rehabilitation where, you know,

0:41:12 > 0:41:15they're learning to use something again that they hadn't had before.

0:41:15 > 0:41:19To test for meaningful vision, the team want to know

0:41:19 > 0:41:24if Rhian can pick out the contrasting hands on this clock.

0:41:24 > 0:41:25I'm thinking 12...

0:41:29 > 0:41:30..three...

0:41:32 > 0:41:35- Mm-hm.- I think three is longer.

0:41:35 > 0:41:39- Have a feel.- Oh, it is.

0:41:39 > 0:41:41Oh, my God!

0:41:43 > 0:41:45- Spot on.- I got it right.

0:41:45 > 0:41:47You did. Well done.

0:41:48 > 0:41:51For the first time in 16 years,

0:41:51 > 0:41:54she's got some vision in her right eye.

0:41:55 > 0:41:59- Honest to God, I felt like Christmas Day there.- That's perfect.

0:41:59 > 0:42:03It's a great start and, over the next few months,

0:42:03 > 0:42:06Rhian's brain will get better and better

0:42:06 > 0:42:09at interpreting the signals to form an image.

0:42:09 > 0:42:11I always think it's very nice

0:42:11 > 0:42:13to compare that to very early TV pictures -

0:42:13 > 0:42:16very, very grainy, black-and-white, just an outline of things,

0:42:16 > 0:42:19moving and coming and going, compared to what we see,

0:42:19 > 0:42:21that is a considered to be a low level of vision.

0:42:21 > 0:42:24For someone who's completely blind, the ability to see people moving

0:42:24 > 0:42:28around in front of them, and shapes, is an actual life-changing event.

0:42:28 > 0:42:30- Three small, 12 big.- OK.

0:42:32 > 0:42:35I really didn't know what to expect, but when something actually happens,

0:42:35 > 0:42:39you think, "Oh, my word," you know, just amazing.

0:42:42 > 0:42:46It's now been six months since the operation

0:42:46 > 0:42:49and although it's still early days, Rhian's brain is starting

0:42:49 > 0:42:54to be able to understand the signals from her eye in three dimensions.

0:42:55 > 0:42:58- So here?- Yeah. Can you find an edge to it?

0:43:00 > 0:43:01Oh, my God!

0:43:02 > 0:43:06The surgery is making her dream of mobility come true.

0:43:06 > 0:43:10Well, it's a mixture of relief and disbelief, really,

0:43:10 > 0:43:14that we've been able to give her some vision back.

0:43:14 > 0:43:18If our results continue to be as promising as they've been so far,

0:43:18 > 0:43:21then it's likely that in the future

0:43:21 > 0:43:24this device may be available on the NHS. That's the hope.

0:43:26 > 0:43:29- No way.- Exactly on it. - No way.- Exactly on it.

0:43:31 > 0:43:34Could you just describe for me what it's felt like for you?

0:43:36 > 0:43:39Well, I was hoping my smile would tell it all

0:43:39 > 0:43:43because just the sensation of...

0:43:43 > 0:43:47You're not completely helpless, that you can usually find

0:43:47 > 0:43:52an edge of a wall and it's... Oh, I really can't put it into words.

0:43:52 > 0:43:54I just felt elated.

0:43:54 > 0:43:55Oh, my God.

0:43:56 > 0:44:01Seeing Rhian using this device has been fantastic.

0:44:01 > 0:44:05The difference it has made in just six months is astounding.

0:44:06 > 0:44:09Now, it sounds like not very much to those of us

0:44:09 > 0:44:11who can see everything,

0:44:11 > 0:44:15but, in fact, for the thousands of people who suffer from these sorts

0:44:15 > 0:44:18of debilitating eye diseases,

0:44:18 > 0:44:22this technology is offering incredible hope.

0:44:22 > 0:44:25There's more information on this and all the other items on the programme

0:44:25 > 0:44:27on our website at...

0:44:41 > 0:44:44At this time of year, we're thinking about getting healthier,

0:44:44 > 0:44:47but how do we know what to do?

0:44:47 > 0:44:51We're told something is good for us, then too much is bad,

0:44:51 > 0:44:55so what are the limits? When can you have too much of a good thing?

0:44:57 > 0:45:00I want to find out the evidence behind some of the things

0:45:00 > 0:45:03that we hear so much about in the press...

0:45:04 > 0:45:09..exercise, body fat, alcohol, meat.

0:45:09 > 0:45:12This time I'm looking at fat.

0:45:12 > 0:45:14How much is too much?

0:45:14 > 0:45:16What are the best ways of measuring it

0:45:16 > 0:45:21and could there be some forms of fat that are actually good for you?,

0:45:21 > 0:45:25Government guidelines centre around a height-to-weight ratio

0:45:25 > 0:45:26called body mass index, or BMI.

0:45:28 > 0:45:30A BMI above 25 is considered unhealthy,

0:45:30 > 0:45:35but BMI had been criticised as a poor measure of obesity.

0:45:36 > 0:45:39And is all excess body fat a bad thing?

0:45:39 > 0:45:43I've come to hear the opinions of two leading obesity experts

0:45:43 > 0:45:45with very different points of view.

0:45:46 > 0:45:50Professor Nicholas Finer thinks that too much body fat

0:45:50 > 0:45:52is almost always a bad thing.

0:45:52 > 0:45:55I would have no doubt in saying that there will be benefits

0:45:55 > 0:45:57from losing weight.

0:45:57 > 0:46:01However, Professor Fredrik Karpe believes that in the right place,

0:46:01 > 0:46:03the more fat, the better.

0:46:03 > 0:46:07The wider the hips, the more healthy you are,

0:46:07 > 0:46:11the less diabetes you have, the less cardiovascular disease you have.

0:46:12 > 0:46:16So how have they come to such different conclusions?

0:46:16 > 0:46:17I want to hear their evidence.

0:46:17 > 0:46:20Fredrik Karpe is Professor of Metabolic Medicine

0:46:20 > 0:46:25at the Oxford Centre for Diabetes, Endocrinology and Metabolism.

0:46:25 > 0:46:29His research focuses on the effects of different types of fat tissue.

0:46:31 > 0:46:34The assumption is that losing weight is always a good thing.

0:46:34 > 0:46:38- Yes, that is an assumption. - And it's one you're challenging?

0:46:38 > 0:46:40I would challenge that, yes.

0:46:40 > 0:46:42There is actually quite good evidence that

0:46:42 > 0:46:47if you are overweight and you have no problems,

0:46:47 > 0:46:51metabolic problems, your have no benefit from losing weight.

0:46:51 > 0:46:54Well, that is quite a radical thought.

0:46:54 > 0:46:57Oh, I wasn't expecting that, right.

0:46:57 > 0:47:01Well, I don't know why there's this vilification of fat tissue,

0:47:01 > 0:47:04because it's actually an absolutely necessary and vital organ

0:47:04 > 0:47:09for the human body, and fat on the leg, around the gluteal area,

0:47:09 > 0:47:14is extremely good at storing fat in a very safe way, so it's tucked away

0:47:14 > 0:47:17and isn't filling fat into other parts of the body.

0:47:17 > 0:47:19OK, so if you've got fat around the legs

0:47:19 > 0:47:23and the thighs and the bottom, is that fat good or neutral?

0:47:23 > 0:47:28I think it's good and there is a good body of evidence

0:47:28 > 0:47:31to suggest that it is actually beneficial to have that fat.

0:47:31 > 0:47:34It's very paradoxical. The more of it you have, the better it is.

0:47:34 > 0:47:36OK, that is paradoxical

0:47:36 > 0:47:39because the assumption is that all fat is bad beyond a certain point

0:47:39 > 0:47:43and you're saying that if you put on fat down here, it is positively good,

0:47:43 > 0:47:47- and is that true for men and women? - Yes, it is.

0:47:47 > 0:47:49Do you actually have evidence that that is good for you?

0:47:49 > 0:47:53The evidence comes from large epidemiological studies,

0:47:53 > 0:47:56so it's fairly consistently been demonstrated

0:47:56 > 0:48:00that the wider the hips, the more healthy you are,

0:48:00 > 0:48:05the less diabetes you have, the less cardiovascular disease you have.

0:48:05 > 0:48:09- I'm aware that if you have a large waist...- Yes?

0:48:09 > 0:48:12..then that puts you at significant risk of developing type 2 diabetes,

0:48:12 > 0:48:16but if you have a large waist but you have even larger hips,

0:48:16 > 0:48:19- would you that suggest your diabetes risk goes down?- Yes.

0:48:19 > 0:48:22There is at least one study strongly suggesting that,

0:48:22 > 0:48:27and we have our own unpublished data showing the same thing,

0:48:27 > 0:48:30so I think one can make a good case for that claim.

0:48:30 > 0:48:38So, if you're a woman and you have a BMI of, say, 28, 29,

0:48:38 > 0:48:40you have quite bit hips compared to your waist,

0:48:40 > 0:48:43is there any evidence that if you lose weight

0:48:43 > 0:48:45that might actually be bad for you?

0:48:45 > 0:48:47No, that study has not been performed,

0:48:47 > 0:48:49so that evidence is not there,

0:48:49 > 0:48:53but you can also turn around the question and say,

0:48:53 > 0:48:58well, that woman with a BMI of 30 and the wide hip,

0:48:58 > 0:49:01possibly doesn't have any complications

0:49:01 > 0:49:07of being moderately overweight, so where is the evidence to lose weight

0:49:07 > 0:49:09when you have no complications of your obesity?

0:49:09 > 0:49:14So, Professor Karpe isn't convinced of the benefits

0:49:14 > 0:49:18of always losing weight, even if your BMI is a bit high,

0:49:18 > 0:49:21and he believes that fat on the bum and thighs is actually good

0:49:21 > 0:49:26for us and can cancel out some of the bad effects of fat on the belly.

0:49:26 > 0:49:30It's a pretty radical view and not one that's shared by everyone.

0:49:32 > 0:49:35Professor Nicholas Finer is a consultant in Endocrinology

0:49:35 > 0:49:40and Bariatric Medicine at University College Hospital, London.

0:49:40 > 0:49:44So if you have a BMI over 25, you're technically overweight -

0:49:44 > 0:49:47is losing weight always a good thing?

0:49:47 > 0:49:52Well, I would say that, yes, it is, except perhaps in the elderly,

0:49:52 > 0:49:57and it may not be a good thing in people who are already ill.

0:49:57 > 0:49:59So what are the benefits of losing weight

0:49:59 > 0:50:01if you have a BMI of, say, over 30?

0:50:01 > 0:50:05There are enormous benefits and we have very good evidence of this.

0:50:05 > 0:50:09We know that the risks of diabetes are reduced by as little

0:50:09 > 0:50:11as a 5% weight loss.

0:50:11 > 0:50:13We know that the risks of heart disease,

0:50:13 > 0:50:17of breathing problems at night, are improved.

0:50:17 > 0:50:20We know that, actually, quality of life improves,

0:50:20 > 0:50:22so the evidence for the benefits of weight loss,

0:50:22 > 0:50:24I think, is overwhelming.

0:50:24 > 0:50:26Where it is problematic

0:50:26 > 0:50:30- is in that normal range and slightly overweight range.- So 25 to 30?- Yeah.

0:50:30 > 0:50:33And what we do know is that fat in different places

0:50:33 > 0:50:36- has different risks.- And where is the worst place to have it?

0:50:36 > 0:50:39Almost certainly the worst place to have it is in your belly.

0:50:39 > 0:50:43That is the wrong type of fat, which causes consequences

0:50:43 > 0:50:46such as diabetes, hypertension, fatty liver disease.

0:50:46 > 0:50:52- Do you think that some fat can be healthy?- Oh, absolutely.

0:50:52 > 0:50:55I mean, first of all, we need energy stores in our body,

0:50:55 > 0:51:00so we need some fat, so storing fat is necessary,

0:51:00 > 0:51:03but we don't need as much as most of us have.

0:51:03 > 0:51:07In terms of, say, fat on the buttocks and the lower part,

0:51:07 > 0:51:09do you believe that they're protective?

0:51:09 > 0:51:13We're not in a position, if you like, to do a prospective study

0:51:13 > 0:51:16where we get people to either store fat down there

0:51:16 > 0:51:19or store fat in the belly and that would really be,

0:51:19 > 0:51:22it would seem to me, the way to answer that question.

0:51:22 > 0:51:25And in terms of the hip-to-waist ratio,

0:51:25 > 0:51:27do you ever measure it in your patients?

0:51:27 > 0:51:30At an individual clinical level, I don't like waist-to-hip ratio

0:51:30 > 0:51:33and the reason for that is that a waist-to-hip ratio doesn't change

0:51:33 > 0:51:36when you lose weight, because if you lose weight from your waist

0:51:36 > 0:51:38and from your hips, it comes down.

0:51:38 > 0:51:42And in terms of your age, I've seen studies which suggest that

0:51:42 > 0:51:48after the age of, say, 65, then a BMI of 25 to 30 is possibly protective.

0:51:48 > 0:51:49Yes.

0:51:49 > 0:51:51Things change as you get older.

0:51:51 > 0:51:57OK, as you get older, the ratio of fat to lean tissue may change,

0:51:57 > 0:52:00so people may have not only excess fat,

0:52:00 > 0:52:03but particularly low levels of lean tissue.

0:52:03 > 0:52:06- Yes, muscle.- Yes, muscle and bone.

0:52:06 > 0:52:10And if these people lose weight, they may lose some fat,

0:52:10 > 0:52:16but they may end up with unhealthily low levels of lean body mass.

0:52:16 > 0:52:19So you don't think there's a real paradox there at all?

0:52:19 > 0:52:20The problem is

0:52:20 > 0:52:23when you start applying this to the population as a whole.

0:52:23 > 0:52:27We know that as BMI goes up, the risk of diabetes,

0:52:27 > 0:52:30heart disease, etc, all increase,

0:52:30 > 0:52:35and there are large numbers of prospective studies that show that.

0:52:35 > 0:52:39We know that weight loss improves all of those parameters.

0:52:40 > 0:52:45Professor Finer believes total fat loss is always a good thing

0:52:45 > 0:52:47if you are obese by a measure of BMI,

0:52:47 > 0:52:50but BMI is the best measure we currently have,

0:52:50 > 0:52:55and you can't argue with the links between BMI and disease risk.

0:52:56 > 0:52:59So, after hearing the evidence on both sides, time for me

0:52:59 > 0:53:01to decide what I believe.

0:53:03 > 0:53:05Well, that was absolutely fascinating.

0:53:05 > 0:53:08Professor Karpe obviously believes that if you're pear-shaped,

0:53:08 > 0:53:09there are lots of advantages.

0:53:09 > 0:53:11Professor Finer thinks it is absolutely pointless

0:53:11 > 0:53:14measuring your waist and your hips.

0:53:14 > 0:53:16I think I go with Professor Karpe on this one.

0:53:16 > 0:53:20As to how much fat is too much, well, both of them agreed -

0:53:20 > 0:53:23it depends on whether it is making you sick,

0:53:23 > 0:53:27then that is too much and you should do something about it.

0:53:36 > 0:53:39Over the past month, we've been running an experiment

0:53:39 > 0:53:43to test a brand-new theory, that men burn more fat through the day

0:53:43 > 0:53:46if they've exercised on an empty stomach

0:53:46 > 0:53:49and women if they've exercised after eating.

0:53:50 > 0:53:53Three mornings a week, two groups of volunteers

0:53:53 > 0:53:56have been on an identical programme of exercise.

0:53:56 > 0:53:59They've also had an identical liquid breakfast -

0:53:59 > 0:54:04one group before they exercised and the other group after.

0:54:04 > 0:54:07- How did you find the whole process? - I enjoyed it, yeah.

0:54:07 > 0:54:09Zumba on a Friday morning is definitely an eye-opener.

0:54:09 > 0:54:13Felt better, slept better, performed better.

0:54:13 > 0:54:16- What time were you waking up in the morning?- About 6.15 in the morning.

0:54:16 > 0:54:19- Do you think you'll stick to that? - No.

0:54:20 > 0:54:23Prior to this, I probably had the fitness levels of a pork scratching,

0:54:23 > 0:54:25- but now I feel like I'm much fitter. - Yeah?

0:54:25 > 0:54:28Much more lively, a healthier pork scratching.

0:54:30 > 0:54:34So our volunteers are certainly feeling fitter,

0:54:34 > 0:54:36but is there any difference in how they're burning fat?

0:54:38 > 0:54:42Before our volunteers started the experiment, Adam Collins took

0:54:42 > 0:54:46a baseline measurement of how much fat they were burning at rest.

0:54:46 > 0:54:48Now he's repeating that measurement.

0:54:48 > 0:54:52Each volunteer will find out if they're burning more or less fat

0:54:52 > 0:54:54than when they started.

0:54:56 > 0:54:58It's time for the results.

0:54:58 > 0:55:02First up, the group who exercised after eating.

0:55:02 > 0:55:08Men on my left and women on my right. Now open your envelopes.

0:55:08 > 0:55:12Those of you that have got the same, so you burnt the same amount of fat,

0:55:12 > 0:55:13just stay where you are.

0:55:13 > 0:55:17Those of you that were worse, take a step back.

0:55:17 > 0:55:21Those of you that were better, take a step forward.

0:55:22 > 0:55:25Most of the men are now burning less fat

0:55:25 > 0:55:27compared to when they started,

0:55:27 > 0:55:31whereas most of the women are burning more.

0:55:31 > 0:55:33Group 2, you're on.

0:55:34 > 0:55:37This group exercised on an empty stomach.

0:55:37 > 0:55:40Compared to the last group, the men are burning more fat

0:55:40 > 0:55:43and the women are burning less.

0:55:43 > 0:55:47On average, the women were nearly 22% better off

0:55:47 > 0:55:49exercising after eating

0:55:49 > 0:55:55and the men were 8% better off exercising on an empty stomach.

0:55:56 > 0:56:00So what can explain the difference between the sexes?

0:56:00 > 0:56:03Since this is a brand-new finding, we're not yet sure,

0:56:03 > 0:56:07but it may have something to do with the way our bodies handle

0:56:07 > 0:56:12the different types of food we use as fuel - carbohydrates and fat.

0:56:12 > 0:56:16Both men and women will store carbohydrate in muscle

0:56:16 > 0:56:19and men have more muscle than women,

0:56:19 > 0:56:24so they have got a greater capacity to store and utilise carbohydrates.

0:56:24 > 0:56:28So they're really designed to burn carbohydrate preferentially,

0:56:28 > 0:56:29compared to women.

0:56:30 > 0:56:36So men are built to burn carbs and if they eat before they exercise,

0:56:36 > 0:56:39they'll have such a ready supply of carbohydrates

0:56:39 > 0:56:42that that's mainly what their bodies will use

0:56:42 > 0:56:44and the effects last throughout the day,

0:56:44 > 0:56:48so to avoid this and burn more fat instead,

0:56:48 > 0:56:51they need to do their exercise on an empty stomach.

0:56:51 > 0:56:53And the women?

0:56:53 > 0:56:56Women have more body fat and less muscle mass,

0:56:56 > 0:56:59so women, if you feed them carbohydrate,

0:56:59 > 0:57:02they still will be able to burn fat

0:57:02 > 0:57:05because they're better designed to burn fat during exercise.

0:57:08 > 0:57:12And our results suggest that women actually burn more fat

0:57:12 > 0:57:14if they've done exercise after eating.

0:57:14 > 0:57:20# The female of the species is more deadly than the male... #

0:57:20 > 0:57:24What I've seen here has been really startling.

0:57:24 > 0:57:28When it comes to burning fat, it seems what's good for the goose

0:57:28 > 0:57:31isn't necessarily good for the gander.

0:57:31 > 0:57:34Women should definitely eat before they exercise

0:57:34 > 0:57:37and men should eat after.

0:57:37 > 0:57:41Getting this right can help us to lose that spare tyre

0:57:41 > 0:57:44and become healthier into the bargain.

0:57:54 > 0:57:58So when it comes to exercise, we've discovered some very useful cheats.

0:57:58 > 0:58:03It's important to keep your muscles strong, as well as getting a workout,

0:58:03 > 0:58:07but you can do that with just a few well-spent minutes at home.

0:58:07 > 0:58:11Protein supplements and fancy sports drinks are a waste of money.

0:58:11 > 0:58:15And when you do your workout - if you're a woman, do it after eating,

0:58:15 > 0:58:19whilst if you're a man, do it on an empty stomach.

0:58:19 > 0:58:22That way you'll be burning more fat for many hours afterwards.

0:58:24 > 0:58:26That's it from Manchester.

0:58:26 > 0:58:29Next time, we're in Surrey where we're finding out

0:58:29 > 0:58:33if simply changing the time of day you eat can make you healthier...

0:58:34 > 0:58:38..asking could diet products be making you fat,

0:58:38 > 0:58:40and how much is too much alcohol?

0:58:48 > 0:58:53# I just made an appointment for a special rendezvous

0:58:53 > 0:58:57# To see a man of miracles and all that he can do

0:59:03 > 0:59:05# Doctor, I want you

0:59:05 > 0:59:07# Mmm, my doctor wanna do

0:59:07 > 0:59:10# I can't get over you

0:59:10 > 0:59:13# Doctor, do anything that you wanna do. #