Newsletter #177: How to Maintain a Sharp Mind đ§
Guten Morgen, humanOS friends! đ This week, we looked at some basic lifestyle factors that are linked to better brain function later in life. Your brain is kind of what makes you who you are, so there isnât anything more important than that, right?
The Roman poet Virgil wrote, âTime robs us of all, even of memory.â We have long recognized the insidious toll that aging takes on the body â including the brain. But it is only fairly recently that we have been able to seriously conceive of ways to reverse the process. Fortunately, there are actually some super simple things that you can do right now to keep your mind in the best shape possible, and itâs never too early (or too late) to start.

Most of what we are talking about here revolves around a concept known as cognitive reserve, meaning the mindâs resilience to damage to the brain. Cognitive reserve is partially determined by genetics, but appears to also be cultivated through lifestyle factors like education, mentally demanding work, physical activity, and intellectual pursuits. Basically, if you consistently use your brain, youâre more likely to remain sharp and productive as you get older, which is pretty awesome if you ask me. To learn more, scroll on down đđŒ
This Weekâs Research Highlights
âĄïž Mentally stimulating jobs are linked to lower risk of dementia in old age.
An international team of researchers examined the relationship between cognitive stimulation at work and risk of dementia in 107896 people. They found (as youâd generally expect) that risk of dementia was significantly lower for subjects with high cognitive stimulation at work, compared to those with lower stimulation, and this association remained after adjusting for relevant factors like age, sex, education, and lifestyle. To get some insight into what was going on in the brains of these individuals, the researchers looked at a random sample of 2261 subjects and took blood samples. They identified three proteins in the blood that were linked to increased risk of dementia, and that were significantly lower in the participants with high cognitive stimulation. How come? Previously experimental work from tissue cultures and animal research suggests that these proteins are involved with nerve degeneration, and may make it harder for brain cells to form new connections, which is key for learning, memory, and other mental processes. So, mental stimulation may quite literally change your brain.
đ§Â  Postponing retirement until the age of 67 appears to slow cognitive decline.
Researchers analyzed data from 20469 participants in the US Health and Retirement Study, all of whom participated in the labor market sometime between 1996 and 2014. They found that postponing retirement to age 67 was associated with a 30-34% reduction in cognitive decline, and this protective effect appeared to hold regardless of gender, educational attainment, or occupational attainment. This appears to lend further support to the notion of cognitive stimulation and cognitive reserve having an insulative effect on the brain during aging. Additionally, this is a particularly encouraging finding as governments around the world have been looking at increasing the retirement age to lower costs. Co-author Angelo Lorenti says: âOur study suggests that there may be a fortuitous unintended consequence of postponed retirement.â
đ»Â  Internet use after retirement is associated with better cognitive function.
Could scrolling through Reddit make you smarter? Well...maybe. In this study, researchers examined cognition in a sample of 2105 older adults in Europe who had been retired since 2004. Participants were tested on their cognitive function in 2013 and 2015. In one such test, individuals were asked to recall a list of ten words immediately, and then again five minutes later. The researchers found that internet use was associated with better performance on this word recall test. On average, people who used the internet after they retired were able to recall 1.22 extra words in the recall test compared to non-internet users. This protective effect was particularly pronounced amongst female subjects: Women who regularly surfed the internet were able to recall 2.37 more words compared to women who didn't go online. Co-author Colin Green says: "Within our study we estimated statistical models which controlled for individuals' ages, education levels, occupational skills and years since retirement, so we are confident that our results are robust and relate only to the use of the internet, post retirement.â Probably worth noting that this study didnât look at specific internet activities, but I would have to imagine that some uses are more beneficial than others.

Random Trivia Question of the Week
đ€Â How old is the world's oldest (verified) living person?
đĄÂ Answer
Podcasts We Loved This Week
- Lucy Mailing: Rewilding the gut - restoring ancestral diversity to the microbiome. Via Nourish Balance Thrive.
- Douglas Boyes: Nighttime streetlights are stressing out urban insects. Via Science Friday.
Products We Are Enjoying
Duolingo
While we are on the subject of cognitive stimulation, research also suggests that language learning can help keep your brain youthful, and bilingualism is associated with better cognitive function later in life. You definitely wonât achieve fluency using Duolingo in isolation, but it is a fun and accessible platform that offers bite-sized, image-driven lessons, and lots of positive reinforcement for daily use (I am currently maintaining a 553 day streak đ ). Best of all, itâs free, though it does also provide a premium service if you are keen to avoid ads.
humanOS Catalog Feature of the Week
Thank you so much, as always, for reading, and see y'all next week!