last year, i travelled to california to see the latest innovation aiming to help us live healthier lives for longer. this time, i'm back to look at our brain health. social interaction is basically exercising your brain. i meet the scientists and experts investigating what we can do to reduce our cognitive ageing. what you see here is six different major circuits of the brain. could we bend the arrow of alzheimer's disease . risk down on itself? hey, you must be lara! hello! i visit the residents of one of the world's blue zones... i don't smoke, i don't drink alcohol, and i'm a vegetarian. ..and catch up with the tech entrepreneur trying to turn back time on his body and mind. it's going to feel like the womb. i can't remember what that felt like! they laugh.

i'm visiting one of the world's so—called blue zones to find out why its residents live longer, healthier lives than average. many of those in loma linda, california, are seventh—day adventists — a religious group that really values health and community. hey, you must be lara! hello! yes. awesome! lovely to meet you. so good to meet you, lara. would you like for me to prepare you a breakfast? oh, yes, please. 0h! that would be lovely. that would be awesome. what i can see already here looks very healthy and very tasty. yes, we enjoy fruits and nuts and grains and all of this stuff. you've actually become really involved in the community here, even though you weren't born here? no, i'm originally from the netherlands. actually, when i came, it was a culture shock. of course, being a catholic

and coming into seventh—day adventists, they were very, very much reserved. and at that time, i consumed alcohol, which i do not any more. i don't smoke, i don't drink alcohol, and i'm a vegetarian — you might say 99% vegan. we want to eat healthy. we want to exercise, because my body is the temple of god. so if i stay strong, and clear—minded... ..i�*ll be of service. living this life is centred around what the adventists refer to as the "health message". healthy lifestyle is to refrain from... refrain from... ..unhealthy activities. more family—oriented lifestyle, fruits and organic vegetables

and everything organic — no chemical sprays — and then exercise. you know, fresh air, community and spiritual. is loma linda a happy place? is loma linda a happy place? it's a happy place it's a happy place to be, absolutely. to be, absolutely. yeah, it's a happy place. yeah, it's a happy place. and happiness is good and happiness is good for your longevity. for your longevity. exactly. mm—hm. exactly. mm—hm. exactly. exactly. they may credit the religion, they may credit the religion, they may credit the lifestyle, they may credit the lifestyle, but there's no great secret — but there's no great secret — they're simply living they're simply living a really healthy life. a really healthy life. at these assisted living here in loma linda, at these assisted living apartments, esther has already apartments, esther has already been to her daily exercise been to her daily exercise class. class. what is your age, if you what is your age, if you don't mind me asking? don't mind me asking? you don't know yet? you don't know yet? i don't know yet. i don't know yet. i'm glad you're sitting — i'm glad you're sitting — i'll be 100 in august. i'll be 100 in august. you're going to be 100? you're going to be 100? that is amazing! that is amazing! how old do you feel? she chuckles. she chuckles. i feel older i feel older than when i was 80. than when i was 80.

lara laughs. lara laughs. do you think being do you think being here in loma linda, within this kind of community, is what is responsible for you being so good for your age?

exists here, community spirit is strong. what i didn't realise was how important socialisation is to your brain, and without it, it seems to shrink and go away. and so the ability to just have heart—opening, brain—opening conversations is very, very, very important. and that mental stimulation matters. as we get older, our brains shrink. we lose brain cells and brain connections. this can impact our memory and our attention spans. it doesn't happen to everyone equally, though. our bodies age, our brain ages at different speeds, based on different things. there are 87—year—olds that are sharp as a whip, and part of it's genetics and part of it's lifestyle. the life you lead informs your genetics and your genetics then expresses itself based

on the interactions you have with your environment, which is why social interaction is so important. social interaction is basically exercising your brain. as we start to understand more about how it works and ages, experts are taking advantage experts are taking advantage of the power of ai of the power of ai and big data. and big data. it helps them see patterns it helps them see patterns of how cognitive decline can play out and indeed, of how cognitive decline can the disease process when it comes to when it comes to something like dementia. something like dementia. but also other sources... but also other sources... andrei irimia researches brain ageing. based on data from 15,000 to pick up on them. based on data from 15,000 brains, he's aiming brains, he's aiming to provide a better way to provide a better way of predicting decline. of predicting decline. it's looking at a lot it's looking at a lot of different patterns related not only to shrinking of different patterns related of the brain, but also change in the properties change in the properties of the signal and intensity of the signal and intensity on these mri scans. on these mri scans. so it's a very sophisticated so it's a very sophisticated way to look at patterns way to look at patterns that we don't necessarily know that we don't necessarily know

about as humans, but about as humans, but the ai algorithm is able the ai algorithm is able to pick up on them. would you be able to identify early signs? what sort of uses are there in this technology for helping with dementia? so this shows differences in ageing between cognitively normal adults and patients with alzheimer's disease. everywhere you see either red or blue, those are areas where ageing is occurring in a different way in the reason this is red is because this is in an area of the brain called the medial temporal lobe, heavily involved in memory, which is important in memory formation. and what we see in alzheimer's is that you have degradation of the ability to recall memories and also to encode new memories. so the work you're doing here, what sort of impact can that have on both diagnosing and potentially even treating alzheimer's? so if we can identify individuals whose brains are ageing a lot faster and estimate their risk for disease a lot better,

so that either clinicians can provide custom tailored treatment, or individuals themselves can implement lifestyle changes.

mri scanners, just like all technology, are getting faster and better and cheaper, so it's becoming much more accessible for people to get an mri scan, and the images coming off of them are getting even better and better. the technology's just getting to a point where we are able to see things much earlier than we could in the past, and that means we can understand exactly what's happening in an individual patient's brain. and now, with al, we can support that. and that could change the game. wow! what is this? it could also give you a nice new ornament. oh, my goodness! a gold version of my brain with my name under it. is that life size? i am a professional rejuvenation athlete. i love it. tech entrepreneur bryanjohnson is spending millions trying to turn back time on his body.

if it can be measured, we'd do it. i visited him last year to unearth his extreme and sometimes controversial regime of fitness, fasting, a load of tablets, tracking and treatments, and i'm back to see how it's going. it's three steps, no rail. 0k. and i have to do this now. he laughs. oh, yeah. nice work. it really hits the... a little bit imbalanced, but generally... yay, i did it! yeah, goodjob. well done. how old am i?! a lot younger than a lot of people who pass through the house. we're back in the clinic. yeah, we're back. so if you step over here... ..on top of this. 0k. and then hold it here. right. and then i'll turn it on. but first, let me give you eye protection. lovely. thank you very much.

what is this actually going to do to me? it's going to make you feel — it's going to give you energy. you love energy. is this going to feel like lying in the sun? it's going to feel like the womb. i can't remember what that felt like! they laugh. are you ready? wow, it's bright — even with these on my eyes. i do it for accelerated healing, blood flow, even for mood improvement. it does feel a bit like that warmth from the sunshine, which does make you feel quite happy. and this is going to give me energy? it will. can you talk me through what you're looking at in your heart health we have made great strides in, my bone mineral density, my strength. can you talk me through what you're looking at in your brain, and then any kind of interventions you're doing to try and reverse that biological age? we look at the brain several ways. one, we look at the anatomical structure with mri. so the brain shrinks and changes over time. so you're looking

at the actual brain. and then functionally, you're looking at how it actually works. but then what can you do next? so we've done several things. like, last year, when we spoke, i mentioned that i had internal jugular vein stenosis. so i had problems where my posture was poor like this, and it actually... certainly not now. yeah, i fixed it. yeah. and it lessened my blood flow, and so with bad posture, i had white matter hyperintensities. this is like a scarring for the brain. when i fixed my posture and i did the physical therapy exercises, i reduced my white matter hyperintensities by nine years. so i dramatically reduced my brain age by fixing my posture. all of this is, of course, just one person's experiments and he's testing all sorts. well, i would ask if we're going cycling, but it's attached to something, so i don't think we are. what is this? the theory is that this therapy can improve concentration, peacefulness, improve sleep and may also improve the white

matter hyperintensities. so it may improve damage that's caused in the brain. there's no evidence on this, so we're experimenting — as we do with a lot of things. so i do this every day for ten minutes — if you want to try it out? i'd love to try it out. i doubt i'm actually going to feel anything in the time that i put it on, am i? but maybe i'm going to be incredibly sharp and clever later. 0k. what's it actually doing? how does it work? so just like you're familiar with red light therapy for the body... yeah. ..for improved healing, it's the same thing for the brain. just a wavelength that's optimised to go through the skull and the skin and get to the brain. what we have to remember is that if you do an experiment on an individual, that is very different than an experiment on a population that can be peer reviewed and replicated. we know the importance of social interactions when it comes to feeling young. and that sense of community and talking to people really helps us feel our best, often. but you don't like talking to people, especially

after 8:30, when you go to bed. so don't you think you need to do a bit more socialising if you're doing everything to try and reduce your biological age? yeah. um, uh, yeah... i would say i am more an introvert than an extrovert. i do socialise quite a bit. so i'll gather people together at my house, we'll have a dinner and we'll talk about the future of being human. maybe, though, we can learn something from the animal world, and one company has been researching ground squirrels, like this one behind me, to see what they're gaining from hibernation. they may have come out to play today, but this lot spend half the year going in and out of a state of intense hibernation. their body temperature drops and their metabolic rate is turned down to just 1% of normal.

as they're leaving hibernation, they have this amazing adaptation where they're able to regrow these neurones and they're able to have these neuronal connections again. biotech company fauna has been tracking the animals, aiming to develop drugs to replicate these benefits in humans. as they re—emerge, a swab is taken for further investigation. back here in the lab, there's a biobank of squirrel tissue cells here in the corner. but after that, it becomes all about experimenting on human cells and seeing what can be replicated in them. one side of the coin is looking at alzheimer's disease patients and saying, "what's different about their proteins?" "which genes are active or not active?" and then we compare that to the opposing biology of the squirrel, that we know can modify the protein in a good way and regrow the neurones. but does that translate into humans? yes. essentially, we only

look at genes that are highly similar to humans. so we're talking about 90% of the protein or more looks exactly like the human protein. spending six months a year underground isn't generally an option for us, but getting good sleep is crucial. sleep is the single most effective thing that you can do each and every day to reset your brain and body health. there is no operation of your mind that isn't wonderfully enhanced when you get sleep, or demonstrably impaired when you don't get enough. professor matthew walker spends most of his waking hours talking sleep and analysing that of patients in his sleep clinic. this is where the staff will be monitoring the patient. these are nets that we place

on your head, and it allows us to precisely measure exactly where we need to place the electrodes consistently on every head. and we've got your data. these sorts of experiments teach matthew and other sleep experts a lot. your brain has a cleansing system. we knew that your body had one — it's called the lymphatic system. you've heard of that. we didn't think the brain had one, but it does, and it's called the glymphatic system, named after the glial cells that make it up. it was specifically during sleep and during deep sleep that this sort of, you know, power cleanse for the brain began to unfold. why is this relevant for alzheimer's? because two of the pieces of metabolic build—up, of this detritus that was washed away by the glymphatic system during sleep were things called beta—amyloid and tau protein, which are two of the culprits underlying alzheimer's. there is a silver lining

in all of this story of dementia and sleep, because maybe we can do something about it. you don't start to see the decline in your deep sleep that is associated with alzheimer's risk in your 60s or70s, it's already under way. it begins in your late 30s, we can start to detect that decline. so what if i could shift from a model of late—stage treatment to a model of midlife prevention, and could we start to help the brain at that midlife stage? and in doing so, could we bend the arrow of alzheimer's disease risk down on itself? it's notjust sleep that's coming under the spotlight. there's increasing research into the long—term impact of depression. what we've developed is a way to directly measure how your brain functions. and in doing that, we can understand the root causes

of mental health disorders such as depression. someone might say i feel like i cannot experience happiness i don't want to engage in life, it is very general, what is underlying there, what is the root cause? and the breakthrough here is the fact that you can actually see this on a scan. you can see depression. exactly. what we've been able to do is take that complexity and measure what we call the kind of superhighways, the primary connections involved in how we think, how we feel, and what gets disrupted. the presence of having depression does increase the risk for later—life conditions — some dementias, other chronic diseases, as well. data from 6,600 people's brains has been analysed to understand what looks healthy and how signs of depression can show up. what you see here is six different major circuits

of the brain, and they're engaged in functions like, how we think, the one in red, how we feel positive emotion, the one in purple. depression, sadly, it affects people when they're very young. all six parts are important. these schools out of one to ten, ideally, somewhere around five, five .5 is the middle range and that is the healthy average. depression, sadly, it affects people when they're very young. very often the onset is late teens, early 20s. and so if you don't find a way to understand that and treat — ultimately prevent — you're going to have the chronic effect of that dysfunction, disruption in the brain across your life. piano music: amazing grace. # amazing grace,

# how sweet the sound... music is a big part of life here at loma linda, and there could be some brain gains. recent studies suggest that learning a musical instrument, or even singing throughout your life, could benefit your brain health in later years. playing the piano was seen to be particularly beneficial to memory and problem solving. # than when we've first begun.# very nice! it's not only about staying sharp, though. healthy, happy ageing is about the whole package. mildred was a doctor. she even set up a hospital in uganda and was working in health care in loma linda. you're 103, aren't you? yes. that's an incredible age. how old do you feel? i'm getting like a worn—out model t that's falling apart. lara chuckles.

how would you describe your quality of life at this point? pretty useless. i would never recommend and say, "ok, you pick "being old as the way you're going to end your life." forget it. you've lived quite some life and you've had to go through a lot to reach this age. do you recommend living into your hundreds or not? i don't think i'd recommend anything about life and its length... ..to anybody. take it as it comes. i have tried to... ..be happy. and i've managed pretty well. going from talking to bryan

johnson to someone who's103 made this all seem very real. we need to look after not just our bodies, but our minds. it's just a matter of how important being able to quantify that is. it's certainly going to make a difference when it comes to research in the future, and the power of ai and big data is making a lot of that possible. it'sjust, right now, there is no silver bullet. the power of this computational biology and ai will be to help you understand yourself over time and what the things you do benefit you. technology is helping us understand and predict like never before. we know better than ever what we should be doing to look after ourselves. but perhaps mildred should have the last word. you absolutely need to be very careful with your diet. it's true. but i'm not down for any, "you've got to do this and this

"and this and absolutely not touch this." do you think it's more important to live? i think it's more important to live. hello there. the weather's looking very mixed this weekend. yes, there will be some rain at times, temperatures a bit disappointing, but things are set to warm up as we push into next week, especially for england and wales. so, we will have some rain around at times this weekend, mainly across northern and western areas, though for saturday, it's the south which will bear the brunt of some of the wettest of the weather. will be quite mild to begin saturday in the south, a bit cooler further north

where we have more clear skies. but outbreaks of heavy and persistent rain affecting much of the channel islands into central and southern england, southeast wales, up into the midlands and across into eastern and southeast england. we have a met office yellow warning for the far southeast of england because we could see in excess of a couple of inches of rain here. that could lead to some localised flooding, some standing water on the roads. has been very dry across the southeast, though, for all of august. so this is very much needed rainfall — a good drink for the gardens, but it will be very wet through the morning. eventually, it clears out into the afternoon and we should see sunshine and some heavy, maybe thundery, showers moving in, too, but it does brighten up elsewhere across the country. it's a bright day from the word go with sunshine and showers, but disappointing temperatures —16—18 celsius. that is below par for the time of year. saturday night's dry, quite cool, chilly for many, single digits across the board, but it will be turning a bit milder, wetter and windier out west as the next weather system starts to make inroads for sunday, and you'll see more isobars on the chart so it will be a breezy,

blustery day on sunday, with most of the rain in the north and the west. so, quite a wet day, i think, for northern ireland, increasingly so for scotland, northern and western england and wales, maybe a few showers getting into the midlands. but i think the southeast quadrant tending to stay drier, closer to high pressure to the south, so could be up to 20 degrees given some brightness, but rather cloudy skies and again disappointing further north — mid—teens. that system moves away during sunday night into monday. it's a bank holiday monday for many. a ridge of high pressure will start to build in a bit more strong, stronger across the south, so i think england and wales largely dry. we should see some sunshine around, but another area of low pressure will bring more of a breeze, cloud, outbreaks of rain to the far west of the uk, but temperatures responding up to 23 degrees in the south. and that's the sign of things to come. for this upcoming week, it looks like summer will make a return, especially for england and wales, where it could be very warm indeed, with one or two spots in the southeast perhaps touching the 30 celsius mark.

live from washington. this is bbc news. german police are hunting for an attacker who killed three people and wounded others with a knife at a festival in the city of solingen. the independent candidate for the us presidency, robert f kenneder,

has suspended his campaign and given his backing to donald trump. and authorities in russia say they've killed four inmates after a rebellion that left four prison guards dead. hello, i'm helena humphrey. we begin with news from germany. police there have confirmed at least three people have been killed and at least four others injured in a suspected knife attack in the western city of solingen. local media is reporting a man randomly stabbed passers—by during a festival in the city centre on friday evening. these are live pictures from solingen. the attacker is still at large, and police have launched a manhunt. police helicopters were seen above the city. celebrations were under way to mark the 650th anniversary of the city's foundation. the city authorities asked people to leave

the area and police are imposing security cordons.