Beaucoup Ways to Sustain Your Brain
Evidence-based ways to help preserve memory, cognition, and superpowers.
A previous article I wrote cast shade upon memory supplements like Prevagen, and was one of the most read and liked posts I’ve done. I promised I would write about evidence-based ways to protect our memory and cognitive abilities. I offer no guarantee that these will work for everyone, or that anything can prevent normal aging. But unlike a bottle of jellyfish protein sold for $60 that has made hundreds of millions of dollars, the post you are about to read has no FDA disclaimer that it might not work. Ok, maybe just one FDA disclaimer for fun… maybe you can find it.
Brain health and memory are some of the most common concerns I hear in the office as people age. But investing in our capacity to learn, remember, and use knowledge is a lifelong imperative. Good cognitive abilities are the most vital part of our human experience. The ideas here should help.
How can we best sustain our brains, and thereby ourselves?
There are many sources giving advice about how to preserve the brain and all its glorious abilities, so assigning a relative weight to each intervention can be very difficult. Is it more important to eat a pint of blueberries every week, or go for a daily walk? It’s hard to precisely rank what is most important, but I’m going to start with a report published in The Lancet, one of the world’s top medical journals. The article, entitled “Dementia prevention, intervention, and care: 2020 report of the Lancet Commission,” lists 12 modifiable factors that together account for 40% of dementia cases.
That means that about 40% of dementia cases could be prevented or delayed by modifying these 12 risk factors, in descending order:
Hearing loss (8.2%, most impact in midlife). I was surprised by how important this modifiable risk factor really is. We’ve all had the experience of shouting to a loved one whose hearing is in decline. It is self-evident how isolating and disconnecting this can be. Hearing keeps us engaged socially and environmentally, and without it the brain declines more rapidly. Overcoming the stubbornness some people have when it comes to getting hearing aids is really important. But many of my senior patients just can’t afford the the $3,000-5,000 cost. Medicare should absolutely cover hearing aids for those who can’t afford them. It would save billions of dollars in the long run. Studies have shown that severe hearing loss increases dementia risk 5 fold. Within just 3 years of starting to wear hearing aids, dementia incidence drops. (Hearing aids would have been covered under legislation passed by a Democratic House in November, 2021, but that bill was killed in the Senate.) As I was writing this the FDA announced a new rule that will allow people to purchase hearing aids without a prescription. This is great news, as only 20% of Americans who need hearing aids have them, and the cost could potentially drop by thousands of dollars. It is also really important to protect our hearing throughout life. Turn down the volume, take caution with earbuds and headphones, mow the lawn with earplugs or noise cancelling headphones, and bravely be the uncool person who wears earplugs at loud concerts. I wish I had done that more often. But I have no regrets about that Radiohead concert at the TLA in Philly, circa 1993.
Poor education (7.1%, most impact in early life). I was also surprised this carried so much importance, but I shouldn’t have been. Investing in early childhood education, good schools, teachers and students is crucial for our economy, society, and health. Pushing through high school to college and beyond has also been shown to give the brain a mighty reserve as time washes away connections. And for those who did not go to college and beyond, lifelong curiosity, reading, and informally educating oneself are also quite protective.
Smoking (5.2%, most impact in later life). Nicotine is not easy to quit. It is a very addictive substance. We all know that by now. Setting a quit date is a great way to gear up mentally, and your doc can help with prescription meds or advice about OTC products like Nicoderm. Second hand smoke is not good either, so helping others quit helps you, too.
Depression (3.9%, most impact in later life). Depression in later years has actually been called pseudodementia. A depressed person can exhibit signs and symptoms of dementia, independent of a true diagnosis. And persistent depression can also cause or accelerate dementia. By preventing, diagnosing, and treating mood disorders, we can improve cognitive status and help ward off decline. Self-help, counseling, medication, exercise, good sleep, good food, and social connections can all help with depression. But simply acknowledging the possibility of this mood problem is a big step.
Social isolation (3.5%, most impact in later life). This dilemma predates the pandemic of course, but the social isolation many people experienced over the past 2+ years was a high cost we collectively paid. It saved millions of lives, and kept everything from collapsing. But it also provided a grim window into how the severing of social ties, community, and even family bonds can accelerate the decline of the brain, most acutely in later life. Reestablishing friendships and social connections is quite important, especially for those who live alone. Hopefully this can be done in a safe way (mindful of ventilation, and the still-churning pandemic that kills 3,500 Americans a week right now). Balancing social life with social caution is still a tremendous challenge, worse for the older generation, as getting Covid is certainly not good for the body or brain, either. More on this later.
Traumatic brain injury (3.4%, most impact in midlife). This is a difficult one to prevent, as no one really sets out to be involved in a car accident or sustain major head trauma. But looking at upstream risk factors that might lead to brain injuries might help us reduce alcohol consumption, drive defensively, wear a helmet skiing and biking, stay off motorcycles, safety proof the home, etc. And when head injuries do occur, we should give our brains the time and rest they need to recover from serious concussions and the like.
Air pollution (2.3%, most impact in later life). There is not a whole lot we can do as individuals to improve the whole world’s air quality, but as a group we need to support leaders and businesses that are part of the solution. Clean air matters so much. Among the little hacks and ways to improve our air quality, usually opening a window is best - unless it’s a really polluted day. Airnow.gov provides forecasts and real time measures of how good or bad the air quality is across the U.S., and can be used to avoid prolonged time outdoors on the worst, Beijing/Delhi-like days. Second hand smoke is harmful, and the list of indoor pollutants in our homes might surprise.
Hypertension (1.9%, most impact in midlife). Newer guidelines emphasize aiming for a systolic blood pressure less than 130. Keeping weight down, reducing stress, cutting back added salt, eating clean and healthy… the list goes on. An astute commenter on my last post pointed out that blood pressure goals can be relaxed a bit over age 70, as studies do find a different risk/benefit calculus there. Thanks Bill :)
Physical inactivity (1.6%, most impact in later life). We all know that staying active really helps the body, brain, and psyche. We also know this becomes harder as we age because of physical limitations, pain, and so much good television to stream. I think this 1.6% feels too low. I think it is much more important to avoid being sedentary, and not just for brain function. In terms of the optimal number of minutes to exercise per week… I kind of dislike memorizing that because it keeps changing, and converting “150 minutes of exercise per week” into hours, and then into hours per day, and then back into minutes per day, just makes me want to be mentally lazy. Just stay active - putter, garden, fix stuff, walk, bike, stand up, and do more vigorous exercise if you can.
Diabetes (1.1%, most impact in later life). Elevated blood sugars affect almost every system in the body. Trying to reverse and mitigate the effects of insulin resistance is a major problem, with 55 million Americans predicted to have type 2 diabetes by midcentury. Cutting back on junk (sugar, refined starches, sugary drinks, pizza, ultra-processed food), staying active, and patience with slow and steady weight loss can all help. Nutritionists, medications, and doctors can help, too.
Excessive alcohol (0.8%, most impact in midlife). In a previous post I wrote about the poison and pleasure of alcohol. I tried to present a bit of nuance with respect to alcohol. But on the whole, the risks certainly outweigh the benefits, and the less we drink (unfortunately) the better. A recent study out of the University of Pennsylvania showed that even 1/2 drink per day decreases our brain size over time, equivalent to adding a couple years of wear and tear, and that this atrophy only increases as daily drinks go up.
Obesity (0.7%, most impact in midlife). Weight loss is a struggle. Our bodies try hard not to lose weight. That was our superpower as a species, and helped us survive and feed energy-intensive brainpower. But as the modern world is awash in calories, this superpower has become a liability for many. I’m sounding like a self-referential broken record, but once again, I wrote a post about the idea of boosting our metabolism, and the realistic ways we should plan to lose weight.
I’ll briefly mention another great study, published in JAMA Neurology. This study used a different set of patients and data, and came up with similar factors but with different weighted importance. It might seem confusing that different studies came up with different percentages, but they are at least quite similar in naming the usual suspects. In this study, here is the proportion of dementia cases that potentially would be prevented if a risk factor was eliminated:
Hypertension had the highest weighted population attributable fraction for dementia (12.4%), followed by obesity (9.2%), depression (9.1%), hearing loss (7.0%), traumatic brain injury (6.1%), diabetes (5.1%), smoking (3.2%), physical inactivity (3.1%), less education (3.1%), social isolation (1.9%), vision loss (1.8%), and excessive alcohol consumption (0.3%).
Once again these sorts of studies are not perfect, and the huge difference in estimated importance for hypertension between the two studies (1.9% vs. 12.4%) undercuts the notion that any of these numbers are exact. But we get the general idea!
More Techniques and Practices That Help Our Brains
I’m going to run through some highlights in addition to the 12 modifiable factors listed above. There is some overlap, as many of these factors and tips help reduce multiple risks.
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Try to get better sleep. This helps restore the mind, repair connections, and remove toxic metabolites that have built up from a long day’s mental work. Cerebrospinal fluid actually swells in our brains’ ventricles while we sleep, acting like a liquid garbage truck, cleaning up the junk and emptying the trash cans from the neural streets.
Practice paying better attention. Some perceived loss of memory might actually be from distraction. It takes some mental work to lay down new memories, and if we are multitasking or otherwise fragmenting our thoughts among competing stimuli, encoding memories gets harder for anyone.
Don’t cede too much control to technology. Smartphones like iPhones are miraculous little supercomputers, and when used judiciously expand the power of our brains like tools. But they have also become attention-grabbing, thought-fragmenting, mental crutches that can have a very negative overall effect on cognition. They interrupt conversation, thought, and concentration. As humans we make tools, but those tools then remake us. We invented the hammer, but then using the hammer rewires our brains as we develop aim and 3-D spatial manipulation, and our forearm muscles grow stronger and coordinated through a nervous system running from fingertips to cerebellum. Smartphones reshape our brains in extremely powerful ways, engineered as they are to release dopamine as we sneak a quick fix, and act like a constant tide pulling the mind back to the infinite playground of emails, articles, games, and social media updates. Try to practice putting the phone down for extended periods. Retain an ability to focus during conversation, or during a walk in the woods. Observe and visualize the world with your own eyes and visual cortex instead of snapping a photo and rushing on to the next stimulus. Go old school for a while each day.
Exercise your brain. Read nonfiction. Read fiction. Always try to keep acquiring new skills and learning new things. Play an instrument, or learn how. Play games. Play games with other people. Garden. Sew. Play a team sport. Cook challenging recipes. Practice memorizing poems or short speeches. Take courses. Travel (safely now). The list goes on. Watching television and movies is super fun, but I don’t think it counts. Watching hours of TV or binge watching is actually bad for your brain long term.
Exercise your body. This was previously mentioned in the Lancet study above, as physical inactivity is correlated with dementia. There are tons of studies out there, so I’ll just mention a recent one presented at this year’s Alzheimer’s Association Conference: “Sedentary older adults with amnestic mild cognitive impairment who engaged in regular exercise for a year maintained their cognition without decline, topline data from the EXERT trial showed.” And if you can exercise socially, like walking with a partner, or playing a sport/game together, studies show this is even better.
Eat healthy food. I’m going to quote a good article in from the NYT Well Section: “Two diets in particular, the Mediterranean diet and the MIND diet — both of which encourage fresh produce, legumes and nuts, fish, whole grains and olive oil — have been shown in scientific studies to offer strong protection against cognitive decline.” Think leafy greens. Colorful fruits and vegetables. Fish and seafood. Nuts. Whole grains. Beans/legumes. Olive oil.
Don’t eat much unhealthy food. Another study from just a couple weeks ago reinforced the notion that highly processed junk foods corrode the brain. The findings of this study showed that people who consumed 20% or more of their daily calories from ultra-processed foods experienced a much faster decline in cognitive performance over the span of 6 to 10 years versus people with healthy diets. In the average American diet, 56% of total calories come from ultra-processed foods. A second recent study showed that for every 10% increase in daily intake of ultra-processed foods, people in the U.K. had a 25% higher risk of developing dementia. Don’t think hot dogs. Ice cream (I know, it hurts to write this). Sugary drinks. Most instant and frozen meals. Regular bread. Crackers. Cakes and pies with infinite shelf lives. Donuts. French fries. Chips. Sweetened cereal. Cookies. Fried snacks. Cream cheese. Candy. And yes, over-sweetened chocolate bars.
Improve your vision. The Lancet study at the beginning of this post showed just how important good hearing/hearing aids can be. But another modifiable risk they did not include, but the JAMA study did, is how important improving vision can be. One study found that cataract surgery reduced the onset of dementia by 30%. Vision loss can lead to changes in brain structure and function, and can increase isolation and loneliness. This is similar to what hearing loss does.
Read a newsletter. Reading this letter has done more for your brain’s health than a year’s worth of Prevagen, and you saved almost $700 dollars. That’s enough to cover a subscription to 12 more great Substack newsletters. Your stamina for getting this far is impressive, and appreciated! We’re almost done.
Write a newsletter. Composing these posts has helped me shake off some mental rust. Writing engages so many neglected parts of the brain, and synthesizes connections. I think I have redeployed my electronic-medical-record-hobbled brain here in ways that have reclaimed something. Stringing words together, learning how to do the tech behind publishing, learning how to do a podcast, and engaging with commenters in meaningful dialogue back on the website lights up a bunch of dark roads deep in my otherwise tired, burned out brain. Writing will help you, too, even if it’s just a real letter to a friend.* *This statement has not been evaluated by the Food and Drug Administration.
Try not to keep getting Covid. The end game should never have become just staying out of the hospital, or not dying. The risks of brain fog (which is a diminishment of cognitive function) go up every time we get Covid. A study out of China predicts a major uptick in dementia rates and cognitive impairment, especially among those who develop severe Covid syndromes (much less likely in vaccinated, boosted, up to date patients). On the other hand, a lot has been written about the social isolation and loneliness of this pandemic, and how that has also had a detrimental effect on world cognition. Finding a safe-ish balance is key. The outdoors make for a lovely social setting, and masking indoors in crowded places and on planes absolutely helps. Etc. Etc.
I hope this post has given you a pretty comprehensive review of the major modifiable risk factors implicated in up to 40% of dementia cases. Cognitive decline is a universal phenomenon, but it can be delayed or prevented in many cases. It is important to think about this at all ages, from the child who should be encouraged and supported in their education, to the elderly person with bad vision and hearing who could really benefit from an intervention. Eating healthy, exercising, putting down our phones, sleeping better, and all the common sense behaviors we need to reinforce also overlap with preventing and treating conditions like hypertension, diabetes, and obesity. It all makes sense, really.
I’ll plan on breaking out the new mic soon to record the 2nd ever Examined podcast - reviewing, expanding, and riffing on this post. As I stated earlier, consider leaving a comment as a supporting subscriber, and I’ll work it into the dialogue. Talk soon!
Double bravo! BRAVISSIMO! Although all of the installments of this newsletter have been very helpful, this latest one about preventing dementia is probably the most comprehensive and most important article to date. So many risk factors are avoidable, and the consequences of the disease are so tragic that the information and ideas in this article can be considered life saving.
This post is fantastic. I have a lot of comments, but I'll just share this kind of "meta" one - reading longform articles like this can feel pretty exhausting, and is evidence that our brains have become accustomed to short cuts like tweets and fluff. Taking the hard and long road at times when reading/learning is really important. Thanks for this good mental exercise in and of itself, not to mention the good content presented.