Do you want to keep your brain sharp? This is all it takes

In general, challenging yourself is key in any job.

"Try to approach your tasks in a different way than you usually do. Ask your colleagues for advice, seek new input, do something else. It doesn't matter if it's slightly uncomfortable; the brain will only react even stronger

Try something new

Troels W. Kjær himself has incorporated various brain challenges in his everyday life:

"I travel a lot with my work and have decided that I need to learn just a few words wherever I am; it may be two words in Polish. And at least every other time I take the metro, I must try to strike up a conversation with a fellow passenger, even though it's difficult with everyone looking at their mobile phones."

Reaching out in this way may cross your boundaries and therefore be a challenge that is good for the brain. In addition, according to surveys, being social and cultivating your relations are inherently important to your mental health.

Work helps shape our brains

Your work and how much it challenges your brain capacity have, without a shadow of a doubt, a huge impact on how your brain develops and is maintained.

This also appears from a new study recently published in the journal Neurology.

More than 7,000 Norwegians with 305 different jobs are included in the study. It shows that those with the least mentally demanding jobs had a 66 per cent greater risk of mild cognitive impairment and 31 per cent greater risk of dementia after the age of 70 compared to those with the most mentally demanding jobs.

The study took into account a number of factors that could affect the result, meaning that the result that remained would solely reflect the job's mental effect on the brain.

"Of course our work affects the development of our brain. We spend a lot of time at work, and if we spend it doing too much of the same thing, the neural synapses won't develop in the same way," says Troels W. Kjær.

"We have long known that the risk of dementia is higher in social class 5 than in social class 1. There is a clear link between work and brain health."

Thicker cerebral cortex

The outermost layer of the cerebrum is called the cerebral cortex. If unfolded, it would require a head with a diameter of 60 cm. Luckily, the cerebral cortex is instead folded, giving the characteristic and familiar curled appearance.

When we push ourselves by giving the brain new exercises, it forms new paths and connections, i.e. synapses, and actually grows – the cerebral cortex becomes slightly thicker. But there is no reason to worry as there is plenty of space, promises Troels W. Kjær.

Four factors

Work is naturally not the only factor that is relevant to brain health. There are four general factors, the neuroscientist lists:

"If we consider the things that keep our brain working well, they are:

Using it – and not on too much of the same thing

Staying physically active – make it part of your daily routine to take the stairs and go for a walk around the office building.

Eating healthy – avoid saturated fats, eat berries, nuts, fatty fish and dark chocolate.

Taking breaks – both during the day and in the form of a good long night's sleep so you get into that deep sleep where the brain works like a washing machine and refreshes the brain."

Unlike the body's other organs, the brain is not able to cleanse itself of waste products while we are awake.  It takes sleep to start the brain's cleansing system, the glymphatic system.

Slower with age

Regardless of what you do to keep your brain fit, you can't prevent it from slowing down your learning capacity little by little.

"Young children spend around 30-40 per cent of their energy on powering their brain. Their brain has a high degree of plasticity and empty connections that are ready to learn, including words. This is the reason why young children are able to learn how to speak a language fluently."

As adults, we spend less and less energy on our brain, around 20 per cent. At the same time, the cerebral cortex shrinks by two per cent per decade.

"The decline starts in your mid-20s, and then it's all down hill from there. I've always been good at IT systems, but it's not as easy as it once was to learn something new. On the other hand, by the end of your working career, you have gathered a lot of experience for your brain to draw on," says Troels W. Kjær.

If you want to combat the loss of capacity, you may, as mentioned, make a difference by using your brain as well as your body:

"In terms of physical activity, studies show that four hours of light physical activity a day makes a difference. It's a lot for most people, so it needs to be incorporated into your day," says the neuroscientist, who is also author of the book 'Did Einstein work out? (Gik Einstein til fitness?)"

Of course, he did not, but the man who came up with the theory of relativity was diligent about taking brisk daily walks right up until his death. Today, we know that his actions thereby affected the well-being of his brain.

Testing on mice even indicates that physical activity of the male mouse in the time leading up to mating may be decisive for the intelligence of the next generation. 

Forget your activity tracker

As a head doctor and professor, Troels W. Kjær has also been engaged in the influence of sleep on the brain, including the connection with epileptic seizures.

In addition, he has been involved in examining how good the very popular activity trackers are at detecting sleep quality.

"Sleep is of concern to many, and it's widely understood that it's not just an unimportant break. But activity trackers are not accurate when it comes to sleep. When we measure the brain during sleep and compare it to the results of activity trackers, 70 per cent are fairly accurate, while the rest are completely off. That's quite a margin of error."

His advice is to try not to worry about sleep, but attempt to achieve inner balance and create a good sleep environment, for example, by removing all electronic screens from the bedroom.