How do we keep our brains youthful, healthy and functional for the entirety of our lives?
Until recently, the answer might have been a shoulder shrug or a glib ‘no idea’.
But our armoury against brain ageing has grown dramatically in recent years and I am among a small but growing number of physicians who no longer believe that cognitive decline is inevitable or that neurological disease is your fate if you happen to have inherited the wrong kind of genes.
It used to be widely accepted that our hearts would simply weaken with age, that cancer was a death sentence and that conditions like Type 2 diabetes couldn’t be prevented let alone reversed.
Today we know better. We know there is plenty we can do to strengthen our hearts; that cancer can often be spotted early and treated effectively; that lifestyle changes can help keep diabetes in check.
Well, the good news is key interventions can also make a dramatic difference to our long-term brain health. What is more, it’s never too early – or too late – to start.
How do I know? Because as a neurologist at the forefront of research into Alzheimer’s disease, I have worked with people who, by making often small but impactful changes to their lifestyle and nutrition, deploying what my team and I dubbed the ReCODE Protocol (short for reversal of cognitive decline), have managed to slow, stop and, in many cases, reverse their slide toward dementia, results which have been backed up by our published clinical trials.
Dr Dale Bredesen says he and his team have managed to slow, stop and, in many cases, reverse a patient’s slide toward dementia
The enemies of a fully functioning brain are depressingly common features in our everyday lives: from ultra-processed food to obesity, pre-diabetes, overstimulation, infectious diseases, stress, exhaustion, difficult relationships, surgical procedures, viruses and accidents, for example.
But as I will explore in this series taken from my new book The Ageless Brain, the antidotes are also readily available to us.
With just a few tweaks to your daily habits, sleep patterns and diet, you can take better care of your brain. You can have sharper thoughts, crystal-clear memories, increase your ability to learn new information and have the capacity to take better control of your moods and emotions.
What’s more, if you keep working at it, you can retain these powers until you’re 100 years old. Longer, if the birthdays keep coming.
Many people have told me that their greatest fear is living into old age without being able to think rationally, remember reasonably, and recognise loved ones. But it really doesn’t need to be that way.
The problem is many people still wait far too long to start the mitigating work – ten or even 20 years after the brain changes leading to dementia have begun.
We have seen our protocol work wonders even in these cases: alongside the return of many memories, I have seen patients start to recognise loved ones and engage with them again. Their speech and ability to care for themselves may even return.
Those who start the protocol in the earlier stages have returned to normal cognitive function. These are the world’s first Alzheimer’s survivors, the pioneers who have led the way to a better life for everyone down the line.
Think about it: if the ReCODE protocol can provide a much better life for people at the end of their journey and reverse the decline of people in the earlier stages, then if we move upstream to people who have no symptoms, we should be able to prevent cognitive decline altogether.
There is so much you can do to increase your ‘brainspan’, assuring an ageless, active brain for life. Consider that possibility for just a moment: a world in which we think clearly, learn and remember, throughout our lives, without worry. One where, no matter how old you get, a high-performing brain that you’ve future-proofed from degeneration can become your greatest possession.
This is my hope for all of us, and something I believe to be entirely possible. So today and tomorrow, I will show you how…
Know your brain’s enemies
Cognitive decline and neurological diseases, including dementia and Alzheimer’s, are by-products of the litany of assaults our brains encounter throughout the course of our lives. Which is why protecting the brain in the first place plays such an important role in increasing your brainspan. Start by getting to know the enemies:
Ultra-processed food: One study found that people whose ultra-processed food consumption comprised more than 20 per cent of their daily calories had a 28 per cent faster rate of cognitive decline than those who ate fewer UPFs.
Why would this be? A big part of the answer is almost certainly fibre, which ultra-processed foods lack, meaning nutrients move through the body before they can be used.
Meanwhile, carbohydrates get absorbed faster, triggering inflammation and raising insulin levels – two big enemies of brain health because of how they cause brain cells to die and increase risk for Alzheimer’s.
Avoiding UPFs means ditching anything our ancestors wouldn’t recognise as food along with products which contain additives, food colouring, stabilisers, deodorisers, or neutralisers. Find out what you need to eat to support memory and brain health in tomorrow’s The Mail on Sunday.
Obesity: One of the reasons improving your diet plays such a pivotal role is because of the knock-on effect it has on some of the other assaults on our brain health.
Obesity is a big one, having been linked to cognitive impairment, brain atrophy (the loss of brain cells called neurons, as well as the loss of connections that help cells communicate) and impairment of synaptic activity, the neural network through which electrical or chemical impulses travel.
One meta-analysis of 13 studies that all ran for multiple years, each including at least 1,000 subjects, concluded that obesity in midlife almost doubles the risk of Alzheimer’s and dementia.
Poor oral health: At first it was assumed that dental problems – from tooth decay to cavities, gingivitis and halitosis – were a symptom of cognitive decline on the basis that people who were having trouble with their memory were more likely to forget about oral hygiene. But it’s now become clear that dental problems typically precede symptomatic cognitive decline.
While the oral cavity is home to many harmless bacteria, it’s also where you’ll find some harmful ones, most notably Porphyromonas gingivalis. If this is allowed to live in a person’s mouth for too long, it can cause serious infections and lead to inflammation. Furthermore, this same microbe has been found in the brains of patients with Alzheimer’s.
While we know that inflammation anywhere in the body can lead to neuroinflammation, it’s worth remembering that the oral cavity is really close to the brain, and that the two share many of the same bacterial species.
Viruses and inflammation: If you were among the many millions of people who suffered from brain fog during or following a bout of COVID-19, you know how much a pathogen can impact your memory and ability to concentrate.
When researchers in the US reviewed the records of more than 6 million people during the first year of the pandemic, they saw clearly that those who had COVID were at significantly increased risk of a new diagnosis of Alzheimer’s within the next year. Infections can have a powerful impact on our cognitive health and we should do all we can to avoid them. Well-tested vaccines can be a substantial part of this strategy.
Influenza, pneumonia, tuberculosis, and shingles (HVZ) vaccines have all been shown to reduce the risk of neurodegenerative disease, likely because by preventing or diminishing these infections they lessen the lifetime burden of neuroinflammation, benefitting brainspans.
It’s not just illness and disease that can increase inflammation. Poor diet and stress can also trigger an immune response in the brain, which can tip it towards degeneration.
Stress: High-pressure work environments, sleeplessness, difficult relationships, surgical procedures and accidents can all push the nervous system into overdrive, producing excess cortisol (a stress hormone) that can then exacerbate cognitive decline.
Even watching TV, a pastime we associate with relaxation, can bump up our cortisol levels if the content is overstimulating.
Cortisol is a hormone with the almost magical capacity to immediately raise the amount of glucose in our blood, resulting in a surge of energy that permits us to either confront or flee danger.
But for brains that are already running like racing cars, too many energy surges can tax the machinery.
Of course, stress is an element of life we can’t always control, and it’s the chronic, ongoing stress, not the occasional stress, that damages cognition. Meditation, yoga, improved sleep and other stress-reducing approaches, which we will further explore tomorrow, play an important mitigating role.
Toxins: There’s growing evidence that exposure to toxins is tied to the development of dementia. Tiny amounts of toxic exposures occur daily – in your own home, during your commute, and in your place of work. But while there’s little hope of avoiding all of these, there are steps you can take to limit exposure including keeping your house well-ventilated and cleaning away black mould (which can cause damage and inflammation throughout the body, so wear a mask) the minute you spot it in your home.
Thankfully our bodies contain a dynamic filtration system that is designed to excrete and inactivate the many toxins to which we are exposed.
We can help this process by eating healthy foods (especially high-fibre foods and crucifers such as Brussels sprouts and broccoli), exercising often, getting plenty of restorative sleep, and eliminating sources of negative stress in our lives, thus providing our bodies with the resources needed to detoxify.
Don’t become a creature of habit
Neuroplasticity is the brain’s ability to change and adapt due to experience. It’s what allows us to keep learning. But like a muscle, this part of the brain needs regular flexing to keep it in good shape.
This neural network is also the storage site for an astonishing quantity of memories. Your brain can store 2.5 million gigabytes of data, which is as much as a few thousand home computers.
But we need to learn how to continually reboot our supercomputer brains to avoid the systematic breakdowns that lead to cognitive decline.
To do this requires a little re-organisation in our day-to-day lives. Consider, for instance, what you do most mornings of your life.
The neurologist recommends striving to take on a small new cognitive challenge each day, a medium new cognitive challenge each month, and a big new cognitive challenge each year
Do you wake up in the same bed, in the same room, in the same home, in the same town? Do you shower in the same place, using the same soap, drying with the same towels?
If you begin your day with a coffee, do you use the same mug, is it brewed in the same machine, and do you drink it in the same spot as you do most other mornings, or get it from the same coffee shop on your way to work?
There’s nothing wrong with any of this. It’s how most of us live and, in fact, our lives would be chaotic if they weren’t organised in these sorts of ways.
The issue for our brains is that these habits require very little neuroplasticity. We are relying on connections that were created in our brains years – even decades – ago to survive.
This is why, in many cases, we begin to notice our struggles only when our environment changes.
Once, a patient told me that she only began to worry about her cognitive health after her company changed locations. Almost a year after the move, she still found herself driving to her old office on occasion.
We used to think of situations like this as being related to people being ‘absent-minded’ or ‘set in their ways’.
We now know that there is a neurological explanation: they’ve formed such deep and lasting connections in their brains for certain daily functions that the opportunities to form new connections from day to day, month to month, and year to year have become limited.
So, how do you get flexing your brain again? It’s actually quite easy to organise our lives in ways that allow us to consistently create new neural pathways. We obviously can’t change everything about our lives every day, but I don’t think we need to.
Instead, we should be striving to take on a small new cognitive challenge each day, a medium new cognitive challenge each month, and a big new cognitive challenge each year.
Here a few suggestions to get you started:
If you’re a regular crossword puzzler, it’s not just a new crossword you need to try, but a new type of puzzle altogether, such as a sudoku
Daily cognitive challenges
A small flex would be almost anything that requires you to engage your memory, attention, language, perception, problem-solving or decision-making in a way that encourages you to do something differently than you’ve done before.
- If you’re a regular crossword puzzler, it’s not just a new crossword you need to try, but a new type of puzzle altogether. So, a cryptogram, or a solitaire game, or a word search, or a sudoku.
- If you go to the same coffee shop each morning, choose a cafe you’ve never been to before (and perhaps order a different drink from your usual).
- If you work from the same desk at home each day, try temporarily setting up your office at a different location and perhaps start and finish at a different time.
None of these need to become new habits and, in fact, the point is that they aren’t something that continues day after day – they simply interrupt normalcy to provide your brain with an opportunity to create new connections.
Even the act of coming up with 365 different ways to change your daily routine is an exercise in plasticity supportive cognition.
It can be hard at first to get into the habit of this, so keeping a list of ideas for these daily challenges and then journaling what you will do or have done each day is a good way to track your progress and success.
Once you’ve completed a specific daily cognitive challenge, is it off-limits? Certainly not. In fact, it might be very beneficial to go back to a task you haven’t done for a while to re-engage or re-create a synaptic connection that was made the last time.
Monthly cognitive challenges
The key here is to vary not just the activity but the type of activity from month to month – and remember, the aim isn’t to completely master every new thing you try. It’s about expanding your cognitive experiences.
- One month you could read a few books from a very different genre of literature than you’re used to.
- Next you could learn the rules to and then play a new game, such as backgammon.
- The following month you could learn the basics of cooking Japanese food.
- After that you could start listening to jazz.
Annual cognitive challenges
This is a bigger commitment, so it makes sense to align these efforts to grander ambitions.
- If a trip to Florence is on the horizon, an Italian language course may be in order.
- If you’ve become fascinated by chess grandmaster and social media influencer Hikaru Nakamura, perhaps a year dedicated to the study of the game of kings is right for you. True mastery of any subject after just a year of effort is unlikely, but a year of work on anything – even in ten-minute bursts – is guaranteed to result in a better-than-average capacity to understand and engage in that activity for life. None of this should be connected to your profession or an established hobby. If you’re an avid golfer, improving your short game is unlikely to offer neuroplastic gains on a par with taking up oil painting or learning to play the guitar.
Neural plasticity is truly about interrupting the old with the new.
In these daily, monthly and yearly increments, our brains develop the capacity to adapt and flex in the short, medium and long term. This boosts our cognitive capacity to adjust when confronted with other changes in our lives.
- Adapted from The Ageless Brain by Dr Dale Bredesen (Vermilion, £22), to be published March 27. © Dale Bredesen 2025.
The sweetest poison
One of the most common questions I am asked is: ‘What is the single most important thing to do to avoid brain ageing and cognitive decline?’ The thing that would have the greatest impact would be quitting sugar.
Unfortunately, we’re evolutionarily primed to love the stuff because it offers an incredibly rapid burst of energy – the sort of verve our ancestors needed to compete for survival in a world in which short-term performance is evolutionarily prioritised over long-term protection.
Most people, if they were asked to think about the chronic consequences of consuming too much sugar, would likely think about diabetes, which they might associate with a variety of symptoms, like blurry vision, numb limbs, exhaustion, dry skin, slow-healing sores, and rampant infections.
But when I think about sugar, my thoughts immediately turn to the absolute havoc it wreaks on our brains. Sugar gives the brain a quick burst of energy at the expense of long-term protection; the insulin spikes it causes can accelerate both ageing and disease, as well as causing bouts of hypoglycemia, where blood sugar levels drop below normal, which further compromises the brain.
The recent appearance of simple, over-the-counter monitors called CGMs (continuous glucose monitors) has helped many of us to see these increases and decreases in our blood sugar and smooth them out with less sugary diets.
It really is good to talk
Face-to-face social encounters – be that polite small talk with a stranger on the train or a quick chat with a colleague as you share the lift – provide brilliant cerebral workouts.
Here’s what happens in a human brain during a conversation:
- As the interaction begins, sensory information, especially auditory signals, enters our brains and is processed by the respective sensory areas.
- Neurons in the auditory cortex then translate these signals into basic sound units, which are transmitted to other parts of the brain for further processing via neurotransmitters across synapses.
- Now the brain’s language centres light up as a rapid sequence of synaptic transmissions decode syntax, semantics and context.
- Of course, a conversation is not only about listening, it’s also about knowing how to respond, which means the prefrontal cortex is also involved as we decide what to say and when to say it in sequence with the other speaker.
- And since language is more than verbal, the limbic system, a group of structures in your brain that regulate your emotions, behaviour, motivation and memory, helps process emotional clues from the other participant and dictates emotion-signalling responses.
All the while, our synapses, the junctions between nerve cells across which electrical or chemical impulses are passed, are strengthening in some parts and weakening in others as our brains process a flood of new information, while working out whether bits of this chit-chat might come in useful at some point in the future.
