0:00 I recently had a podcast with Dr. Michael Crawford, a renowned scientist who has spent decades researching the evolution of the human brain and nutrition. During the interview, I was amazed by his amazing cognition and memory despite being 95 years old. Seeing that made me think a lot more deeply about the relationship between your brain health and your overall longevity. Many people focus a lot on their body health, their physical health. But I've seen a lot of research suggesting that it might be actually the opposite way. Having good brain health and cognitive health might influence your overall longevity top down, not bottom up. Maybe preserving your cognition and your memory is the driving force behind making your body live longer as well. So, in this video, I want to explore what makes the brains of these super aers so sharp and why good
0:46 cognition may not be just a result of healthy aging, but actually the driving force behind it. Let's start with one of the core ideas we need to know about brain reserve and cognitive reserve. Basically, it's the ability to maintain brain structure and cognition over time the same way you would maintain muscle or your finances. Individuals with higher cognitive reserve are seen to be less susceptible to age related brain atrophy, cognitive decline and dementia. They get fewer symptoms of cognitive decline and neurodeeneration, the higher their cognitive and brain reserve is whereas people with low reserve dip into dementia much sooner. You build cognitive reserve by consistently challenging your brain throughout life. Pursuing education and lifelong learning, learning new languages, and acquiring new skills, engaging in problem solving, reading, writing, and
1:32 exposing yourself to new ideas, maintaining intellectual curiosity and cognitive engagement. Basically, having to flex your mental muscles and encountering brain resistance training, similar to weightlifting. Brain reserve, on the other hand, refers to the actual structure of your brain, the physical tissue. Neurodeeneration is the loss of brain tissue, but with higher brain reserve, you can postpone that. It's found that head circumference is associated with Alzheimer's risk. Women with the smallest head circumference had a three times higher odds of Alzheimer's compared to those with larger heads. Men showed a similar 2x trend, but it wasn't statistically significant. Head circumference reflects a brain reserve. Larger brains and larger heads may tolerate more pathology before symptoms appear. These two concepts are
2:18 fundamental to understand the brains of super aers. Brain reserve reflecting the actual brain tissue and cognitive reserve reflecting your mental capacity. So how do you go about maintaining them? The growth of brain cells is called neurogenesis and creating new connections in the brain is called neuroplasticity. Neurogenesis refers to the birth of new neurons especially in the hypocampus while neuroplasticity refers more broadly to the brain's ability to rewire and strengthen connections. Both are thought to support learning, memory, and resilience. It's been a bit controversial if it's possible to grow new brain cells in your adulthood. A recent study on these super aers and their brains found that they had better preserved neurogenesis profile compared to people with Alzheimer's disease. The paper doesn't prove that they had extra neurogenesis,
3:05 nor that this alone explains better memory, but it shows that the superagers who live longer have more preserved brain function. This figure shows that the superagers immature neurons look different from typical aging and Alzheimer's especially at the level of DNA regulation. The main takeaway is that superagers seem to preserve a healthier, more resilient neurogenesis state. So adult neurogenesis in the hippocampus probably exists and persists. And the difference between healthy aging super aagers and Alzheimer's disease, it's not just that new neurons exist. It's how well that entire neurogenic program is regulated. Healthy aging and superagers have a more preserved resilient neurogenesis profile whereas preclinical Alzheimer's disease and Alzheimer's disease shows an earlier
3:50 and then stronger disruption of that profile. There are more studies on these super aers and it shows they don't just age normally. They have unusually preserved memory and brain structure. They have less age related cortical thinning, a thicker anterior singlet region, fewer Alzheimer's type changes, fewer activated microbia, better preserved coin energy systems, and more neurons. I want to take a quick break to tell you about the Bone Charge infrared sauna blankets. My go-to way of getting 20-minut sauna sessions on the go without needing to spend an hour to warm up a regular sauna. Taking the sauna is, in my opinion, one of the best things for your overall health and heart function. Studies show that taking a sauna regularly is associated with 63% lower risk of sudden cardiac death, 63% reduced heart disease mortality, 46% lower risk of hypertension, and 40%
4:36 reduced all cause mortality. This is mediated by an increase in body temperature and increased heart rate that mimic a cardiovascular workout while at the same time improving arterial stiffness, endothelial function, blood flow, immune system function, blood pressure, and metabolic health. It doesn't matter if it's a traditional wooden sauna, an infrared sauna, and infrared sauna blanket, or anything else that elevates your body temperature above what's normal. One charge infrared sauna blankets have the advantage of shining far infrared light that can penetrate deeper into your tissues than regular saunas can. It warms up in 2 minutes to the optimal temperature of 70° C, and it's low in EMF. You can get a 15% discount by heading over to boncharge.com/seamlund and use the code seam for 15% discount. All right, back to the video. This is where the idea gets very interesting. A sharp brain isn't just a nice bonus on
5:23 top of a healthy body. A sharp brain may actively keep the body healthier top down. Good cognition improves your decision-m self-care balance mobility, social engagement, and the ability to keep adapting. In that sense, cognition is one of the deepest forms of health span. So the next question is how do we actually build this kind of a resilient brain? We don't know how to reliably make yourself a superager. What we can say is that the best supported path is to build the conditions that are most consistently linked to a healthier hippocampus and lower Alzheimer's risk. The short version is exercise, sleep, low chronic stress, metabolic health, cognitive engagement, and a Mediterranean style diet. These are the main levers people take seriously. They're not proven to recreate the exact super Asia signature from the paper, but they're the strongest practical bets.
6:09 When it comes to Dr. Michael Crawford, then he's the researcher that found about the importance of DHA in brain and cognitive development. He himself said that he eats seafood three to four times a week, basically every other day. And DHA is a critical nutrient for brain health. DHA is not the only thing that matters. It's important, but is not the most important thing. The biggest contributor to Dr. Crawford's excellent cognition at the age of 95 is his insane cognitive reserve. He's been in academia for 70 years. That's longer than half a century of cognitive problem solving, researching, and learning. His earliest paper was published in 1957. That's 69 years ago. And his newest paper was published in 2025. The man is still doing research and writing scientific papers while being 95 years old. That's
6:55 the absolute critical part here. Use your brain or lose it. A recent study about cognitive training emphasized this exact point. They looked at if even episodic cognitive training could postpone Alzheimer's and other related dementias. The short answer is yes. They looked at older adults from the famous active randomized control trial, a large cognitive training study in older people and followed them for 20 years. The trial tested three kinds of brain training, memory training, reasoning training, and speed of processing training plus a control group. The training period lasted only for 10 sessions over 5 to 6 weeks. Each session was about 60 to 75 minutes only. Memory training is simple. Try to remember stuff. Reasoning training involves solving patterns and problems. Whereas speed of processing training involves
7:41 training your brain to notice and react to visual information more quickly and efficiently. The key detail here is the booster sessions. Some participants got extra follow-up training sessions after the main training, and that turned out to matter a lot more than the initial training. They got four booster sessions at 11 months and four booster sessions at 35 months. So, some people got 10 original sessions and others got eight extra booster sessions, 18 sessions in total. Over the full 20-year follow-up, the overall cumulative dementia burden was high. In the control group alone, about 48.7% were eventually diagnosed with Alzheimer's disease or related dementias. When you're looking at the specific types of training, then memory training didn't significantly reduce dementia risk. Reasoning training didn't
8:27 significantly reduce dementia risk either. And even speed training by itself wasn't enough to clearly lower risk overall. But there was one standout finding. People in the speed of processing training group who completed one or more booster sessions had a 25% lower risk of diagnosed dementia over 20 years. The study's main message is that one specific type of brain training, the speed of processing training with additional booster sessions may actually delay dementia. Other training methods didn't do that and speed of processing training without the booster sessions didn't do it either. It's speed of processing training with the additional booster sessions. So basically every once in a while, every few years, you top it up with a few booster sessions. In the active study, speed of processing training was designed to make older
9:14 adults get faster at noticing visual information, dividing attention, and spotting something important in the center while also noticing things in the periphery. A simple way to picture it is participants would see very brief visual displays on a screen and had to identify or locate targets faster and faster as the task got harder. The training was adaptive, meaning if you did well, the program shortened display time or make the task more difficult. That's the key part here. If you're already very fast, you're going to get harder training in order to see additional benefits. It's closely tied to something called the useful field of view test. basically how much visual information you can take in accurately at a glance while under time pressure. The time pressure increases cognitive load and the bigger the visual field, the higher the cognitive load as
10:00 well. It's the same way with lifting weights. You need to lift heavier and harder to keep building muscle. Can you incorporate this kind of speed of training tests into your own everyday life? Yes, you can. You can do some real world visual attention drilling. If you're walking in a busy environment, don't just stroll around. Walk while scanning signs, people, obstacles, and the traffic. It's like a real world visual attention drill. Racket sports or fast ball sports are perfect for this. Tennis, pickle ball, table tennis, badminton. These sports constantly force you to track motion, react quickly, and divide and tension. Interestingly, tennis is one of the group sports associated with the greatest life expectancy. Of course, rich people play tennis, but it also has a very good speed of attention testing. Fast-paced video games or purpose-built visual
10:46 attention tasks may also overlap with speed training compared to things like crossword puzzles which require mostly memorization. Dancing or choreograph movement, especially when you have to watch, remember, and respond to moving cues. In an academic research context, the closest equivalents are tasks that train rapid visual attention monitoring and switching without losing accuracy. Instead of doing regular speed reading, it's more like find the question, find the methods, find the main figure, find the limitations, and do that quickly across many papers. The longest living researchers are extremely good at that. The final idea is that your brain aging isn't fixed. Some people stay cognitively sharp into their 80s and 90s because their brain is more resilient. They have better preserved brain
11:32 structure, better regulated neurogenesis, and stronger cognitive reserve, which all seem to be part of the picture. Why would better cognition help you live longer? Because cognition is upstream of your behavior. A sharper brain helps you manage medications, avoid falls, drive more safely, plan better meals, stay socially connected, notice your health problems earlier, and maintain independence. So, cognition is something that doesn't just protect your longevity, it helps to create it. I highly recommend you check out my interview with Dr. Michael Crawford to see yourself what peak cognition at age 95 really looks
