How To Reduce Your Risk of Alzheimer’s and Keep Your Brain Young with Dr Tommy Wood #316
Dr. Tommy Wood, Assistant Professor of Pediatrics and Neuroscience, explains that cognitive decline is not inevitable. He shares simple, enjoyable ways to improve brain health, emphasizing challenging the brain, rest, nutrition (B vitamins, omega-3s), muscle training, social connection, and avoiding toxins.
Deep Dive Analysis
17 Topic Outline
Challenging the Inevitability of Brain Function Decline
Early vs. Late-Onset Alzheimer's and Age-Related Dementia
When Cognitive Decline Begins and Why
Brain and Muscle: A Parallel in Function and Adaptation
The Causative Role of Lack of Brain Stimulus
Practical Ways to Stimulate the Brain After Retirement
The Impact of Technology on Brain Function
Understanding Executive Function and Its Importance
The Value of Learning New, Difficult Skills for Brain Health
Creating Cognitive Decline: Lessons from Animal Models
The Role of Nutrition: B Vitamins and Omega-3s
Navigating Dietary Advice and Individual Variability
Rethinking Gut Health and the Role of Fiber
The Critical Importance of Muscle Mass for Brain Health
Key Blood Tests for Metabolic and Brain Health
The Connection Between Blood Sugar and Cognitive Function
Final Advice for Optimizing Long-Term Brain Health
7 Key Concepts
Neuroplasticity
The brain's ability to adapt and change its structure and connections in response to new challenges, even in older age. This means we can make new nerve cells and connections, and alter the supporting structures around them.
Age-Related Dementia
This refers to sporadic or late-onset Alzheimer's disease, which is highly variable and influenced by environment, genetics, lifestyle, and general health. It differs from early-onset Alzheimer's, which is primarily genetic.
Cognitive Frailty
A state where the brain lacks extra capacity, meaning its maximum function is equivalent to what is required for daily tasks. This leaves no reserve for unexpected challenges, similar to physical frailty where one lacks the capacity to prevent a fall.
Neurovascular Coupling
The process where active neurons in the brain demand more blood flow and oxygen, and the blood vessels respond by increasing supply. Impairment in this coupling due to stiffening blood vessels can hinder the brain's ability to get necessary nutrients.
Executive Function
The capacity to make informed decisions about one's behaviors in the moment, overriding impulses. It involves the ability to control actions and thoughts, preventing impulsive or inappropriate responses.
Metabolic Syndrome
A cluster of conditions including increased waist circumference, low HDL cholesterol, high triglycerides, high blood sugar, and high blood pressure. It indicates systemic insulin resistance and increases the risk of cardiovascular disease, certain cancers, and dementia.
Mean Amplitude of Glycemic Excursions (MAGE)
A measure of how large an individual's blood sugar spikes are after meals. Larger spikes are correlated with pre-diabetes, type 2 diabetes, and worse cognitive function, but this effect is reversible with improved blood sugar control.
8 Questions Answered
While brain function, on average, steadily decreases from your 20s or 30s, it is not an inevitable or unchangeable decline. The brain can make new connections, change its structure, and adapt at any age, allowing individuals to dramatically alter their cognitive trajectory.
Original Alzheimer's disease (early-onset/familial) is rare, caused by a single gene mutation, and leads to rapid decline in the 30s-50s. What most people refer to as Alzheimer's is sporadic or late-onset age-related dementia, which is very variable and influenced by lifestyle, environment, and general health.
Cognitive decline likely begins shortly after the brain finishes developing, around the mid-20s to early 30s. This is often when individuals stop challenging their brains with new learning and experiences, leading to a gradual decrease in function.
A lack of stimulus is a causative factor in age-related cognitive decline, similar to how muscles atrophy without exercise. When the brain is not challenged to learn new things or adapt, its structure and function can diminish over time.
Crosswords and Sudoku may offer some minor benefit, particularly cryptic crosswords, but they are likely not as effective as more comprehensive activities like learning a language or dancing. Once an individual becomes proficient, the challenge diminishes, reducing the cognitive benefit.
Seafood is a primary dietary source of long-chain omega-3 fatty acids, particularly DHA, which is critical for brain development and function. DHA is preferentially incorporated into brain cell membranes and mitochondria, enhancing energy production and synaptic communication.
Yes, individuals on plant-based diets can maintain good brain health. While long-chain omega-3s are primarily from seafood, algal sources are available. It is recommended to test omega-3 levels to determine if supplementation is needed, as some individuals have a genetic ability to convert shorter-chain omega-3s from plants.
Poor metabolic health, characterized by high or fluctuating blood sugar, is strongly linked to cognitive decline and increased risk of age-related dementia (sometimes called 'type 3 diabetes'). The brain can become insulin resistant, impairing its ability to utilize glucose, a vital energy source. Improving blood sugar control can reverse these negative effects on cognitive function.
21 Actionable Insights
1. Regular Brain Challenges
We can improve brain function by challenging ourselves more, as this helps make new nerve cells and connections, and changes brain structure at any age. Stop believing the story that your brain doesn’t work anymore as you get older, because the brain can adapt at any time in life if challenged.
2. Embrace New, Difficult Skills
Focus on learning new skills that you are not very good at, as the challenge of being an amateur provides greater cognitive benefit than being a professional. Choose new skills that you enjoy and can continuously learn and improve at, as enjoyment ensures adherence and long-term benefit.
3. Learn in Short Bursts
When learning new skills, aim for focused 20-30 minute chunks to push the limits of your current ability, as this is the optimal period for cognitive challenge before fatigue.
4. Support Brain’s Adaptation
Support your brain’s ability to adapt to challenges by providing nutrients, sleep, recovery, and avoiding toxins.
5. Prioritize Resistance Training
Engage in physical movement, specifically resistance training, to improve the structure and function of certain brain areas, as well as being your most important glucose sink. Aim for two to three sets per muscle group per week as a minimum effective dose, or 8-12 sets per week for optimal balance.
6. Train to Muscular Failure
When performing resistance training sets, push yourself until you reach voluntary muscular failure (where you can’t do any more reps), regardless of the number of reps, as this is what stimulates strength gains.
7. Incorporate Coordinated Movement
Choose movements with a coordination component, like Tai Chi, yoga, or dancing, for greater cognitive benefit than simple exercise, as they combine music, social, and movement components.
8. Boost Social Connection
Prioritize social connection as it supports both physical and mental health, and its absence is a known stressor in animal models of cognitive decline.
9. Learn a New Language
Learn a language, even late in life, to improve cognitive function and protect certain brain areas.
10. Choose Sustainable, Enjoyable Diet
Prioritize a diet that is accessible, enjoyable, and sustainable for you, as this is the starting point for supporting your health. If your current diet makes you feel great and objectively supports your health, there is no need to change it.
11. Ensure Adequate B Vitamins
Ensure your diet includes a reasonable number of whole foods (plants, vegetables, eggs, meat, fish) to get sufficient B vitamins (B12, folate, B2, B6) for brain health. If vegetarian or plant-based, take a B12 supplement.
12. Optimize Omega-3 Status
Include some seafood in your diet for long-chain omega-3 fatty acids (EPA and DHA), which are critical for brain development and function, and support B vitamin efficacy. If you don’t eat seafood or animal products, consider testing your omega-3 levels and supplementing with algal sources if low.
13. Improve Blood Sugar Control
Actively work to improve your blood sugar control (e.g., by reducing spikes after meals), as this has been shown to improve cognitive function and reverse decline.
14. Monitor Metabolic Health
Aim to avoid increased waist circumference, low HDL cholesterol, high triglycerides, high blood sugar, and high blood pressure, as these are components of metabolic syndrome and indicate poor metabolic health.
15. Target Optimal HbA1c
Aim for an HbA1c level between 5% and 5.5% for the lowest risk of mortality at the population level. If borderline, check fasting blood sugar.
16. Maintain Healthy Waist-to-Height
Aim for a waist-to-height ratio close to or below 0.5, as this is a good cutoff associated with a lower risk of mortality.
17. Use Household Items as Weights
Utilize household items like bags of sugar or cans of beans as weights for resistance training if gym access or specialized equipment is limited.
18. Any Movement is Beneficial
Understand that literally any amount of physical activity, even a brisk walk or short resistance session, is beneficial for your health, so don’t let perceived effort or time constraints deter you.
19. Holistic Health Assessment
Avoid hyper-focusing on optimizing every individual blood test number; instead, consider all results in context with your overall health and how you feel.
20. Maintain Muscle Mass
Aim to be in the top 50% of the population for muscle mass to ensure sufficient strength for health benefits.
21. Maintain Gains with Less Effort
After building desired strength or muscle, you need significantly less training volume to maintain it (e.g., 2-3 sets per week) than to actively build it.
5 Key Quotes
The structure and function of a tissue is directly proportional to the demand you put on it.
Dr. Tommy Wood
If you don't ask a tissue to have a certain function, it will no longer have that function.
Dr. Tommy Wood
You're not allowed to socially isolate the animal and you're not allowed to remove any stimulus from the environment... but you can do it to a human. No problem.
Dr. Tommy Wood
If your model doesn't allow for the individual that is doing amazingly well eating nothing but beef, then your model is wrong.
Dr. Tommy Wood
Physical activity and exercise is the only thing that reverses all of those components, right? It's the only thing that can actively anti-age you in everything that happens as you age.
Dr. Tommy Wood
3 Protocols
General Brain & Muscle Training Protocol
Dr. Tommy Wood- Engage in activities that are difficult and challenging for your brain and body.
- Ensure periods of rest and recovery after challenging activities.
- Choose activities that you enjoy to ensure long-term adherence.
- Consider social activities for added benefits from social interaction.
Minimum Effective Dose Resistance Training
Dr. Tommy Wood- Perform 2 to 4 sets per muscle group per week.
- For each set, choose a resistance (bodyweight, bands, weights) that allows you to reach 'voluntary muscular failure' (where you can't do any more reps with good form).
Optimized Resistance Training for Brain Benefits (Smart Trial)
Dr. Tommy Wood- Train 3 times per week.
- Perform 3 sets of 8 to 12 repetitions for each muscle group.
- Use 6 different gym machines (e.g., row, press, leg press) or equivalent bodyweight exercises.
- Aim for each session to be around 30 minutes.