It's important that you sleep well, going to bed at the same time every night. Photo / 123RF
Lockdowns had a big impact on attention spans and memory, but adopting good habits can bring life-long benefits.
If you'd wanted to devise a plan to damage the nation's health – including our brain health – then you would have come up with lockdown.
For this reason, a new paper on the state of the UK's attention spans and memory did not surprise me. Researchers from the University of Exeter and King's College London studied 6,000 over-50s about their brain health during the lockdown period. Those who suffered from the highest levels of anxiety and depression fared the poorest in cognitive tests and mentally aged the equivalent of six years.
We have long known the devastating effects of prolonged social isolation on our health, including brain health. Loneliness ages us as badly as 15 cigarettes a day, or drinking a bottle of gin, according to a study at University of California, Berkeley. Research over a 12-year period to 2010 from the Harvard Adult Development Study showed that the thinking skills of those who described themselves as "lonely" declined by 20 per cent more than those who were not. Being socially isolated is pernicious and has been robustly proven to hasten dementia and long-term cognitive decline.
Ageing is remorseless: some biologists believe it starts in utero – that we are "conceived ancient". After birth, our risk of death falls till we turn 11 years old, then it starts to rise again. But many measures of ageing aren't noticeable (or more accurately, measurable) until our 70s.
Brain ageing is the result of the accumulation of a wide variety of molecular and cellular damage over time – which is reflected in our thinking skills (which includes memory). As we age, our immune system can start to degrade, meaning inflammation increases in the body. Anything to reduce inflammation will slow down the ageing process, including in the brain where it is associated with pathologies like Alzheimer's Disease.
Brain ageing is hugely individual. In some of us, the process begins early and proceeds quickly; in others, it begins later and at a snail's pace. In everyone, long term memories are very stable but our short term memory lets us down, especially what we call "working memory" – the ability to temporarily retain information to carry out a cognitive task.
To have a working memory is really important: it's how you'll remember the beginning of this sentence to make sense of the end of it. As one gets older, this "short term" memory suffers because the synapses in our brain are less active, but we'll remember things we did years ago because memories made when we were young have been consolidated in the brain.
This new Exeter and KCL study discusses the "over-50s" but it's my view that "chronological age" is not a great guide – though it does enable us to see trends. I'm 72 and I can easily run three miles in half an hour, so my "biological age" is closer to 50. In terms of the brain, some people's brains age faster than others mostly because of environment or lifestyle.
The stress of social deprivation has an inflammatory effect on the brain and the way we handled the Covid pandemic has inflicted on many people the direst of times. Though highly infectious, Covid 19 is of low lethality (one in 524 people) and deaths are found largely in a narrow section of the population. It's therefore entirely reasonable to ask whether the extent of the measures that have been taken to curb the pandemic are justified in relation to the severity of the disease. We already know that there has been a substantial effect on mental health, but we don't yet know the longer-term consequences on brain health.
Despite all this, there is cause for optimism. The pandemic – and its lockdowns – were temporary, but good habits can bring life-long benefits to brain health.
Only 25 per cent of our ageing, both physical, and mental, is determined by our DNA. The other 75 per cent is lifestyle and our environment – over which we have a lot of choice. Here's how we can put our boot on the throat of ageing, rebuild our brain resilience and mitigate the effects of lockdown...
Gardening, cycling, exercising as vigorously as you can: these are great for brain health and many people did fewer such activities during the lockdowns. We know from scientific studies that aerobic exercise produces proteins in the muscles, such as irisin, which travel to the brain and provoke the release of another protein called BDNF (Brain Derived Neurotropic Factor). And its importance? It generates new neurones, essentially rejuvenating the brain. Even better, a study in Madrid in 2019 found that "neurogenesis" takes place until our 90s. You don't have to slog it out in the gym either; I make sure I walk the dogs for two miles every day and run for a mile on the treadmill on alternate days. But there is little point in exercising if you are just going to sit down for the rest of the day. Exercise is not an antidote for sloth. Prolonged daily sitting down is the enemy of brain health.
Many people's routines went to pot during the pandemic. Constantly varying bedtimes, unguarded excesses and irregular habits are bad for you. As well as exercise, make sure you eat regularly at the same times and sleep well, going to bed at the same time every night.
There is a myth that your sleep needs change with age, but this isn't necessarily true. Older people still need seven or eight hours within a 24-hour period, but you don't need to do this all in one go. Afternoon naps of no more than an hour are to be encouraged.
The Harvard Adult Development Study found that those who had good-quality relationships – friends who cared, dependable family – were happier, healthier and had better brains in the long-term. Keep in touch with your friends by any means: phone, email, writing letters or Zoom, though overdoing screen time, especially at night, is not a good idea as it floods the brain with blue light which arouses the brain and damages our sleep patterns.
Don't limit your social interactions to friends and family. The little things in life also count: saying hello to your neighbours or chatting to the shop assistant. Social connections are necessary as food or water.
Frequent sexual intercourse with a close partner can foster better memory, better verbal fluency and even better numeracy skills. A study on male rats, put together with a receptive female, found that the number of new cells in the male rat's brain increased massively – and it worked better on the older rats where it had a reverse ageing effect. Interestingly, rats who got dumped in with a strange female were stressed out and, while they still eventually had sex, the brain benefits were much more profound in those regular partner rats.
Three-quarters of all food in shops comes from five animals and 12 plants. Look further afield for more interesting products. By increasing diversity, we resume the lifestyle of our hunter-gatherer ancestors and increase the chance that we ingest all the nutrients vital to brain health. By eating high fibre, non-processed food we also nurture our gut bacteria which are essential to brain health. As a population, we tend to be deficient in five nutrients needed for brain health: vitamins B12 and D, magnesium, zinc, and omega-3. If you eat a balanced diet, you won't need supplements.
In modern life, our ratio of omega-6 (polyunsaturated fats found in processed and ready meals) to omega-3 (found in oily fish) is 20:1. It should be equal. Four 4oz portions of fish a week should go a long way to fixing this.
It's important to stay hydrated and drink a glass of water every hour. There is also lots of evidence that drinking alcohol within the government recommendations is beneficial to our brains. For example, a Californian study in 2018 showed definite benefits for a certain part of our brain matter of moderate alcohol consumption (no more than two drinks a day). I enjoy a glass of claret or a beer in the evening but never on consecutive nights, except at the weekend.
Professor James Goodwin is the director of science and research impact at the Brain Health Network in London. He is the author of Supercharge Your Brain.
As told to Miranda Levy
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