• Three Brain Hacks

    Earlier this month I gave a talk in an achingly cool studio space in Wapping; a short distance east along the Thames from Tower Bridge. This future-proofing healthcare event seemed to be a great success and I even got meet a hero of mine. I’m happy to report that not only is Henry Marsh a well-regarded neurosurgeon and fantastic author (whose book Do No Harm I reviewed here back in 2015), but he is also a brilliant speaker!

    My brief was to open the event with a quick overview of what the brain is, how its building blocks are arranged to accomplish all the marvelous things our brains can do and then offer a handful of tips and tricks that everyone can use to get their brains firing on all cylinders. When I give these talks there is always hard science behind whatever I share with the audience. It occurred to me that flashing up the relevant references on screen is probably not sufficient if people wanted to go back to the original science papers at a later date. In this month’s blog I thought I’d provide a few links to research articles summarising some of the research that motivates me to recommend three brain hacks to help people keep their grey and white matter in tip-top condition.

    SLEEP

    Many people consider it a nuisance to spend 1/3 of life unconscious. In our increasingly busy lives, spare time tends to get squeezed mercilessly and the time we spend sound asleep in bed usually suffers as a result. This is a travesty because it is when we are asleep that the brain does all its running repairs and maintenance work. It is when temporary memories reverberating around the brains neural highways are re-visited, the superfluous ones deleted and more important ones consolidated into long term memory by the laying down of proteins. According to a brilliant study published in the journal Science the metabolic waste materials that build up in the brain over the course of the day are also removed at a much faster rate when we are asleep compared to when we are awake.

    If these metabolic waste materials are allowed to accumulate in brain tissue it can have a negative impact on brain function and can potentially build up to levels that are neurotoxic, hence prolonged sleep deprivation being deadly for all animals. So a huge part of the reason it’s vitally important that we all try to get at least 7 and ideally 8 hours of sleep each night is to give the brain an opportunity to banish as much of these potentially toxic materials from the brain as possible. While the 2013 study was in mice, a paper published this month in the Proceedings of the National Academy of Science also demonstrated that sleep deprivation has a similar impact on the clearance of toxic substances from the human brain too.

    I’ll not go into further detail here as next month’s blog will be a review of Matt Walker’s book Why We Sleep, but I’ll conclude with one more sleep-related tip. It is perfectly normal to feel drowsy in the mid-afternoon. Acting on the urge to have a 15-20 min nap is not just restorative, enabling you to continue your daily activities with greater efficiency but, perhaps even more importantly, it also vastly improves memory retention and creative problem solving. Personally, I take a nap most days. In fact, I’m feeling the urge right now, so I’ll complete this blog once I’ve taken 40 winks (1 nap-wink = 30s ;-)…

    … that’s better! (I genuinely did). Not only do I practice what I preach but I regularly urge businesses to encourage their staff to take an afternoon nap every single time I speak at a business conference. On many levels it is flagrant false economy to allow the myth  that napping is tantamount to laziness to be perpetuated. It simply couldn’t be further from the truth.

    HYDRATION

    Every single morning we wake up dehydrated. That’s because we have to keep breathing 24/7 to stay alive. This is the only way we can keep our oxygen levels topped up (to maximise the release of energy from glucose to keep our vital biological processes ticking over) and to eliminate the carbon dioxide that is a key waste material of this process, which would otherwise increase the acidity of the blood with potentially catastrophic consequences. To keep these gases moving in and out of the bloodstream, the inner surface of the lungs must be kept moist, which means that every time you exhale you are blowing away a little bit of water vapour.

    Assuming we stay asleep for 7-8 hours, we will always wake up a little bit dehydrated, which knocks all sorts of biological mechanisms out of kilter. From the brain’s perspective the most important impact of this dehydration is that it has a negative impact on neural transmission – the capacity for each of your 86 billion neurons to efficiently send electrical messages along their wire-like axons and thereby influence other brain cells. People usually wake up a little bit grumpy because the first thing to go awry when people are dehydrated is mood. The cognitive impairment associated with dehydration also explains why you’re likely to find yourself prone to getting mixed up in the process of executing straightforward tasks. Accidentally putting coffee in the saucepan with the porridge instead of the cafetiere where it belongs is a personal favourite, as is the struggle to find everything needed for the day ahead in the daily rush to get out the door on time.

    Do yourself a favour: make drinking a glass of water (laying in wait on your bedside table) the first thing you do after switching off the alarm to help you minimise the amount of time you spend lacking a sense of humour and unable to perform the simplest of tasks effectively each morning due to a dehydrated brain. Having started the day well, monitor your mood and when you feel irritable, before you try and blame others for being so annoying, think to yourself – when was the last time I drank water? (NB not coffee, fizzy drinks or juice, but just plain, old-fashioned, H2O).

    COFFEE

    There is pretty good evidence to suggest that people who drink a moderate amount of coffee each day have a lower risk of Alzheimer’s disease and also (in men at least) Parkinson’s disease. We still don’t know what exactly it is about the magic bean that confers these neuroprotective effects – the most popular hypothesis is that the benefits arise as a result of all the antioxidants contained in the coffee bean helping to soak up all the free radicals that would otherwise interfere with our DNA.

    Despite these benefits, there are drawbacks to a voracious appetite for coffee. One broadly overlooked peril of the coffee habit is that caffeine has a very long half-life. It takes 6 whole hours to reduce the concentration of caffeine in the bloodstream by half (NB this takes much longer if you’re pregnant or on the contraceptive pill, but less time if you’re a smoker). This means that if you have the equivalent of 4 cups of coffee’s worth of caffeine in your bloodstream at midday, then it will take until 6pm before this has been reduced to 2 cups-worth and 6 hours after that – at midnight – this will finally have been halved again: down to 1 cup of coffee’s-worth of caffeine. Clearly anyone who is in the habit of drinking coffee throughout the afternoon is going to have so much stimulant swimming around their system come night time that it will inevitably interfere with their sleep. We’ve already covered the reason’s why this is bad news for brain health.

    The upshot is this: to avail yourself of the neuroprotective benefits of coffee, without suffering negative impacts on sleep in terms of onset, duration and/or quality, then get all your coffee drinking out of the way in the morning and if you absolutely must take caffeine onboard in the afternoon, then at the very least try to switch to green tea instead (15% of the caffeine in a cup of coffee). The next time a waiter or waitress offers you an after-dinner coffee, feel free to inform them that they are effectively tempting all their customers to play roulette with the health of their brain.

    NEXT UP

    I’m giving another talk at the end of this month – at 1pm on Sat 28th April – at the Leeds International Festival on the topic of how technology impacts our brains. If this is of interest, then tickets are available here – it’s free!

    In addition to these monthly brain blogs, I regularly tweet about brain-related research that hits the lay press (@drjacklewis), I do a fortnightly podcast about the more unusual scientific breakthroughs (Geek Chic’s Weird Science) and in July 2018 my new book Science of Sin will hit the shelves in the UK (11th Sept in the USA).

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  • Green Tea – a “smart” drug? by Dr Jack

    SYBO 1 year oldRoom For One More?

    In the Smart Drugs chapter of the book I wrote with Adrian Webster “Sort Your Brain Out” we argued that of the various nootropics available in this day and age it makes sense to give preference to substances that have been around for eons rather than the new kids on the block. This really is the only way you can enjoy the benefits without having to worry about the potential unknown long term problems and side effects.

    The brain benefits of regular coffee drinking were described, but due to space limitations we were only able to discuss a few other substances. This month’s blog highlights some of the many published studies that have indicated a wide variety of health benefits associated with regularly imbibing green tea – something that people have indeed been doing for hundreds of years.

    Green & Black

    Tea_grade_of_fermentationCamellia sinensis is the name of the plant that gives us white, yellow, green, black and oolong teas. Black tea has more than twice the amount of caffeine as green tea, whilst green tea has more polyphenols (the very antioxidant substances that mop up all those dangerous free radicals). The difference in concentrations of these substances can be accounted for by the fact that black tea requires fermentation before preparation – which increases the caffeine content and decreases the polyphenol content – whilst green tea is prepared from unfermented leaves.

    All The Tea In China

    GreenTeaPotGreen Tea has been used in traditional Chinese and Indian medicine for thousands of years where it has been exploited for it’s stimulant, diuretic and astringent properties; not to mention improving heart health, flatulence and body temperature regulation. The stimulant effects are thanks to the alkaloids contained within the tea leaf including caffeine, theobromine and theophylline. As green tea contains about half the caffeine of black tea and MUCH less than a cup of coffee, dosing yourself with green tea throughout the day is much less likely to disrupt your sleep come bedtime than the other options.

    Typing “green tea” into an internet search engine yields a huge number of websites dedicated to promoting the ubiquitous benefits of regular green tea ingestion to improve the effectiveness of exercise, improving weight loss and even helping to manage diabetes. Of course its always difficult to know which sources you can and can’t trust. Hard data is required to establish whether green tea really does help to ameliorate symptoms of the various complaints for which it has been traditionally recommended.

    Is Green Tea Really Good For You?

    Yes! When individual research studies are published in a peer-reviewed scientific journal they can provide evidence to support or reject any particular scientific hypothesis, but a single study cannot “prove” or “disprove” any given theory. Meta-analyses are much more powerful in this regard because they look at many different studies all investigating similar hypotheses. If, despite being conducted on a completely different group of subjects, often in a completely different location and undertaken by a different group of researchers, they all point towards the same conclusion this provides for a much more powerful argument to support, or refute, any given claim when the consensus points to a benefit. Just looking at the meta-analysis data it has been confirmed that green tea is effective at lowering blood pressure, reducing risk of several different cancers and improving cardiovascular/metabolic health, to name but a few.

    Any Brain Benefits of Green Tea?

    keep-calm-and-drink-green-teaDrinking green tea has long been associated with relaxation and, indeed, scientific investigation has now backed this up. Epigallocatechine-3-gallate, the most active of the tea polyphenols (known collectively as “catechins”) is found in much higher quantities in green tea than other teas and is known to inhibit an enzyme that converts cortisone to cortisol. Cortisol is a so-called stress hormone and cortisone the inactive form. By preventing the enzyme in question – 11 beta-hydroxysteroid Dehydrogenase Type 1 – from doing its job, the active ingredient of green tea is able to reduce levels of the stress hormone. (In case you were wondering, the other 5 catechins are: catechin, gallaogatechin, epicatechin, epigallocatechin and epicatechin gallate).

    Can Green Tea Can Improve Cognition?

    Yes! Anecdotal accounts of the brain benefits of regular tea drinking in the elderly inspired research to establish whether green tea really could improve cognition. Over the last ten years huge amounts of data have been generated on this topic. The more green tea a person consumes, the lower prevalence of cognitive impairment (Full article available for free). Early research trying to ascertain the mechanism by which such benefits are realised demonstrated that spatial cognition was improved in rats that drank water infused with polyphenols from green tea (full article available for free).

    In the last few years experiments dosing healthy, younger humans with green tea versus placebo have demonstrated an increase in functional connectivity between frontal and parietal brain areas during a working memory task (Full article available for free). Bearing in mind that improvements in working memory can translate into better fluid intelligence and therefore a higher score in the IQ test – swapping green tea into your daily hot drink regime might make sense for your brain’s sake as well as your body’s.

    As well as these monthly blogs you can follow me on twitter by clicking here. It’s always great to hear your suggestions on topics for my brain blogs, so please do get in touch by clicking here.

    I also do a weekly science podcast called Geek Chic’s Weird Science which you can download for free from iTunes or alternatively, if you’re not an iPhone or iPad user, you can download/stream it from a variety of online sources such as Podbay, Libsyn, and PodcastChart, amongst others!

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