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

i feel older than when i was 80. lara laughs 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? of course, our religion, i think, has a lot to do with it. it's very interesting to me that i have lasted this long and at night—time, i pray to... for god to help me get up again tomorrow because i have no assurance. what we promote is a healthy way of— what we promote is a healthy way of life _ what we promote is a healthy way of life and _ what we promote is a healthy way of life and if— what we promote is a healthy way of life and if you - what we promote is a healthy way of life and if you want - what we promote is a healthy way of life and if you want a l way of life and if you want a prescription. _ way of life and if you want a prescription, that— way of life and if you want a prescription, that is- way of life and if you want a prescription, that is fine. i way of life and if you want a i prescription, that is fine. and people — prescription, that is fine. and pepple come _ prescription, that is fine. and people come here _ prescription, that is fine. and people come here because i prescription, that is fine. and. people come here because you have _ people come here because you have these _ people come here because you have these hospitals _ people come here because you have these hospitals and - have these hospitals and surgeries— have these hospitals and surgeries and _ have these hospitals and surgeries and benefits i have these hospitals andi surgeries and benefits of modern _ surgeries and benefits of modern medicine, - surgeries and benefits of modern medicine, but i surgeries and benefits of. modern medicine, but you surgeries and benefits of - modern medicine, but you also have _ modern medicine, but you also have the — modern medicine, but you also have the old—skool_ modern medicine, but you also have the old—skool of- modern medicine, but you also have the old—skool of lifestylel have the old—skool of lifestyle and a — have the old—skool of lifestyle and a life _ have the old—skool of lifestyle and a life based _ have the old—skool of lifestyle and a life based on— have the old—skool of lifestyle and a life based on nature - have the old—skool of lifestyle i and a life based on nature and based — and a life based on nature and based on _ and a life based on nature and based on natural— and a life based on nature and

based on natural remedies - and a life based on nature and based on natural remedies asi based on natural remedies as welt — aside from that duty to protect physical health that 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 of the power of ai and big data. it helps them see patterns of how cognitive decline can play out and indeed, the disease process when it comes to something like dementia. but also, other sources... andrei irimia researches brain ageing. based on data from 15,000 brains, he's aiming to provide a better way of predicting decline. it's looking at a lot of different patterns related not only to shrinking of the brain, but also change in the properties of the signal and intensity on these mri scans. so it's a very sophisticated way to look at patterns that we don't necessarily know

about as humans, but 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 patients with alzheimer's. 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. brainkey is one company commercialising this type of research. the platform quantifies how each section of your brain is ageing. to see what it made of how i'm doing, i needed an mri. what this shows is an image of your whole brain, but also, 25 different areas in the brain and the volumes associated. the summary of the brainkey analysis is the brainage, which is an assessment of your general brain health. so your brainage is a3. so that's good news. it's good news. so we would ideally want brainage to be either at or lower than your chronological age. it's always preferable

to have it slightly below. 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 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, good job. 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 what have you achieved? hearing is something we cannot do much about. heart help, 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 i% 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. so one might say, ifeel like i cannot express happiness any more, i don't want to engage in life. it is very general, what is underlying that and 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 and they give away to understand they give away to understand the different types of depressions. the scores at out of one to ten. ideally, five, five .5 is the middle range and thatis 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. the first half of this week brought us heat and humidity quite widely, but over the past few days, we've seen things turning cooler and fresher as well. now, through the course of the weekend, fairly settled. a lot of dry weather on the cards, some spells of sunshine on offer, and another warm day in the south—east on saturday before cooler conditions work across the uk again for sunday. so what we've got is this frontal system starting to work its way in from the west,

so that's going to bring a bit more cloud to parts of wales, northern england, perhaps the south—west of england, southern counties of northern ireland initially too. a few spots of rain if you're underneath this weak weather front here through the central swathe of the uk, either side of that, a little bit more sunshine. northern scotland seeing a bit more cloud, bringing a few showers. not as many as recent days. it won't be as windy here, but still fairly breezy. now in the hazy sunshine down towards the south—east, temperatures again up to about 25 degrees or so, but a fresher feel away from the south—east of england, typically about 12—19 celsius. overnight saturday moving into sunday, and we've still got this weak weather front. it's really quite slow—moving over the next 2a hours or so. eventuallyjust pushing across parts of south—eastern england and east anglia as we start sunday morning. could be the odd spot of light rain, and here around about 13—15 celsius. but, again, a fairly fresh feel to the weather to start sunday where we've got those clearer skies further north. so, sunday, then, initially quite cloudy, perhaps the odd spot of showery rain in the south—east, that should clear away.

and then this cloud in the north just sinks a bit further south. it will be a broken cloud, so there'll be some glimpses of sunshine. also the chance of a few showers, particularly through the spine of england, for instance. temperatures between only about 12—21 celsius, so a few degrees below average really for this time of year. what about the week ahead? well, it looks like we've got a westerly influence to our weather. so although high pressure sits in the atlantic, weather fronts are toppling around the northern side of that high pressure and bringing fronts our way at times. so monday, some rain initially for northern ireland, western scotland, just pushing eastwards through the day. some uncertainty about how far south we will see any rainfall, that front tending to gradually fizzle out further south, i think. so southern england, south—east england, east anglia in particular, could stay dry, 21 degrees or so for the warmest spots, but we're typically looking at the mid to high teens for most of us on monday. and that theme continues, really, for much of the week ahead. after a warm day in the south—east on saturday, slightly cooler conditions with a mixture of some sunny spells and a bit of rain at times, too.

live from washington, this is bbc news. president biden strikes a defiant tone at his first campaign rally since thursday's faltering debate performance. the choice and this election is simple. donald trump will destroy democracy, i will defend it. donald trump claims victory while addressing supporters at a virginia rally. we had a big victory against a man that does really looking to destroy our country. and how a us supreme court decision limiting the power of federal agencies is expected to affect the lives

of millions of americans. hello, i'm helena humphrey. us presidentjoe biden has vowed to stay in the presidential race and defeat republican rival, donald trump, giving no sign he is considering dropping out after a shaky debate performance in georgia. president biden delivered an energetic address to a cheering crowd in north carolina, his first campaign rally since thursday's debate showing. but there have been calls for biden to step aside, including this from the new york times editorial board, writing plainly: "mr biden is not the man he was four years ago.: "mr biden is not the man he was four years ago." biden acknowledged the debate, calling mr trump a genuine threat to democracy. he also responded to concerns over his age, saying he's still capable of doing the job. i know i'm not a young man. let's state the obvious. i don't walk as easily as i used to, i don't speak as smoothly as i used to, i don't debate as well as i used to,

but i know what i do know, i know how to tell the truth.