• Next Time You See Your Parents Make Sure They Eat Their Greens

    How often were you urged to eat up your greens as a child? In my childhood this was a mantra uttered on a weekly basis. At least. I don’t know where my mum and dad got the idea that leafy green vegetables might be good for the health but, according to a recently published study, it turns out they may have been bang on the money. It never ceases to amaze me how often conventional wisdom ends up being proven true.

    A study conducted by Martha Morris and colleagues at Tufts University in Boston and Rush University in Chicago, published in January of this year in the journal Neurology detailed a prospective study of nearly a thousand participants who were followed across a period of ~5 years during which they periodically filled questionnaires about the food they ate and took a cognitive assessment. These individuals were aged 58 and upwards, all the way up to 99 years old. Analysis of the data suggested that: the more often leafy green vegetables were consumed, the slower the rate of cognitive decline.

    Those who ate at least one serving of greens per day achieved scores on the cognitive assessments equivalent to those 11 years younger. So it seems that greens don’t just help youngsters grow up into strong and healthy adults, but they can even help us hold onto our marbles during the post-retirement years.

    This study also tried to establish which of the many ingredients in the leafy greens might be responsible for these impressive cognitive benefits. Greens rich in folate, phylloquinone (aka vitamin K), lutein and kaempferol all seemed to make a big difference, as did alpha-tocopherol, albeit to a lesser degree. Let’s dig a little deeper into which vegetables contain these various goodies so you can start incorporating them into your diet pronto.

    Folate is found not just in dark leafy greens like spinach, collard greens and romaine lettuce, but also asparagus, avocado, broccoli, beans, peas, lentils, cauliflower, brussel sprouts, beetroot, berries (strawberries > rasberries) and citrus fruits.

    Similarly, Vitamin K is found in plentiful quantities in leafy greens like spinach and kale, but also in basil (get your pesto on), spring onions, cabbage, pak choi, chili (hooray!), leeks, pickled cucumber, olive oil and okra (aka ladies’ fingers).

    There’s plenty of lutein in egg yolk, sweetcorn, kiwi fruit, grapes, orange juice and courgette, as well as greens like spinach, kale and lettuce.

    As for kampferol, there’s a huge quantity in capers per 100g relative to that found in kale, and a good dose in dill, cress, chives and broccoli. That said most people will find it an easier and more appetising experience to eat 100g of kale or broccoli, than the same mass of capers, dill, cress or chives.

    The take away message here is that there’s nothing magical about the leafy greens in terms of the chemical ingredients that, once absorbed into the body and brain, lead to cognitive benefits. They do, however, serve to simplify matters. Rather than struggling to recall which of these nutritional goodies are found in which fruits, vegetables and pulses, by making sure you get a good dose of greens on a daily basis, you can be pretty sure that you’re getting most of the vitamins and minerals that will keep your brain ticking over nicely.

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  • Man the Manipulator by Dr Jack Lewis

    We humans have far more control over our environment than any other species on planet Earth. We have developed an innate propensity for making and using tools to such a degree that we can now fundamentally change – through architectural, engineering and scientific innovation – the very environments in which we exist and with which we interact every day.

    In modifying places in which we spend thousands of hours: our homes, schools, places of work and leisure – we exert more power than any other species in shaping our own brains.

    Iterative cycles of human brains adapting to environments and environments being adapted by human brains have enabled our species to thrive in a wider variety of ecological niches than any other mammal across the length and breadth of the entire globe. Of vital importance to our adaptability is the emergence of cognitive faculties enabling us to circumvent the painstakingly slow processes involved in evolutionary change that drive behavioural adaptations in most other multicellular species.

    Darwin’s finches on the Galapagos Islands, for example, had to wait for many generations to evolve a useful adaptation that conferred a survival advantage over their competitors. This is because the vast majority of genetic mutations do not yield any useful, adaptive characteristics. For genetic mutation(s) to result in, say, a beak of appropriate dimensions to access an otherwise inaccessible food source, a great many decades of annual mating must pass before this random process eventually hits the jackpot.

    Humans confronted with a similar scenario would likely invent a tool to access the food in question. Offspring, or anyone else for that matter, could then mimic the movements necessary to successfully make and manipulate the tool. This is all thanks to “mirror” neurons, which provide us with our natural ability to convert observed movements into movements that we perform ourselves (In his TED talk VS Ramachandran describes the importance of mirror neurons quite beautifully). Behavioural adaptation through tool use is thus not, unlike genetic adaptation, limited to being spread down through subsequent generations.

    Humans are not the only creature to use tools. New Caledonian crows are top of the pecking order when it comes to birds intelligent enough to use tools. They use a variety of different tools and in the appropriate sequential order, to obtain a food reward that would otherwise be beyond their reach. Each bird is clever enough to figure this out for themselves, or at least to learn from others, but their capacity to propagate this information beyond their immediate habitat is prohibited by a lack of sufficiently sophisticated communication tools.

    Chimpanzees strip the leaves off of long straight sticks to use the resulting tool as a means to “fish” for termites in a termite mound. However, as E. O. Wilson famously pointed out: non-human primates do not have the necessary intelligence to prepare a neat stack of fishing sticks the night before. Non-human species only make and use tools as and when they are needed. In more recent times exceptions to this rule have been observed.

    It was long thought that we humans were the only species with sufficient foresight to predict the need for certain tools in the future and to prepare them in advance. However a chimpanzee residing in a Scandinavian zoo turned this assumption on its head by building a stack of stones in the morning to hurl at visitors later on once the zoo had opened to the public!

    That said, we still enjoy the unique status of being the only species able to share knowledge of making and using tools through verbal or written communication. This has propagated knowledge of all sorts of tools way beyond our own communities, to other members of our species across the entire globe – eliminating the need to reinvent the wheel and build upon the creativity of others.

    Arguably the kings of tool use (homo sapiens exluded) are surely the bonobos. The below footage shows our closest primate cousin making tools out of stone, just as our caveman ancestors did, and using them to perform a variety of scraping, cutting and boring purposes.

    In addition to these monthly brainblogs you can catch my daily #braintweet several times a day by following me on Twitter.

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