The Diary Of A CEO with Steven Bartlett

Cognitive Decline Expert: The Disease That Starts in Your 30s but Kills You in Your 70s

February 5, 2026

Key Takeaways Copied to clipboard!

  • Alzheimer's disease generally begins in one's 30s, is largely preventable through lifestyle, and being female is the second strongest risk factor after age. 
  • Resistance training, especially heavy lifting (around 80% 1RM), is the most potent exercise for building cognitive reserve by releasing beneficial myokines and growing new neurons in the hippocampus. 
  • Poor sleep, particularly in women during perimenopause due to hot flashes, prevents the glymphatic system from clearing amyloid beta, leading to its accumulation, a key hallmark of Alzheimer's pathology. 
  • Supplementing with high doses of creatine (up to 20g/day in studies) shows significant benefits for brain energy, cognitive function, and even offers protective effects against insults like concussions, stroke, and potentially cancer. 
  • The Anterior Mid-Cingulate Cortex (AMCC), or the 'willpower muscle,' grows when individuals embrace challenging activities (like forcing oneself into the cold or intense exercise) and shrinks when one lives a sedentary life or avoids challenges, linking willpower directly to neurobiology. 
  • To optimize sleep, one should backload carbohydrate intake at night (e.g., starchy vegetables), ensure core body temperature drops by at least two degrees, and consider supplements like GABA for racing minds and Glycine for temperature regulation. 

Segments

Creatine Benefits and Alzheimer’s Mission
Copied to clipboard!
(00:00:31)
  • Key Takeaway: Creatine can mitigate effects of sleep deprivation and protect the brain against concussion and stroke, showing benefits even in Alzheimer’s patients.
  • Summary: Creatine is highly recommended, showing research support for mitigating sleep deprivation effects and protecting the brain from stress and concussion. Studies on Alzheimer’s patients indicated preserved cognitive function and increased energy levels when supplementing with creatine. Louisa Nicola is focused on preventing Alzheimer’s because it generally starts in the 30s and 60 million people worldwide are affected.
Sedentary Lifestyle and Cognitive Reserve
Copied to clipboard!
(00:01:46)
  • Key Takeaway: Prolonged sitting is a disease, but 10 air squats every hour can compensate for a sedentary lifestyle.
  • Summary: Becoming more sedentary is recognized as a disease contributing to poor health outcomes. Performing just 10 air squats every hour can compensate for the negative effects of prolonged sitting throughout the day. Cognitive reserve is the brain’s capacity to withstand stress, and it is built through activities that create new neural connections.
Louisa Nicola’s Mission and Alzheimer’s Scope
Copied to clipboard!
(00:03:03)
  • Key Takeaway: Alzheimer’s disease is projected to triple by 2050, affecting 110 million women, and 95% of current cases could have been prevented through lifestyle changes.
  • Summary: Louisa Nicola is focused on Alzheimer’s because the global prevalence is expected to triple by 2050, disproportionately affecting women. Dementia, including Alzheimer’s, is not a natural part of aging but a disease of midlife, typically starting in the 30s. Crucially, 95% of current Alzheimer’s cases are considered preventable, as the disease is driven primarily by lifestyle rather than genetics.
Cognitive Reserve vs. Brain Atrophy
Copied to clipboard!
(00:09:52)
  • Key Takeaway: Cognitive reserve, built by novelty and utilizing neural connections, determines whether an individual shows symptoms despite having high levels of amyloid beta plaques.
  • Summary: Cognitive reserve allows the brain to overcome stresses like infection or sleep deprivation, explaining why some older adults remain sharp while others decline. Connections between neurons (dendrites and dendritic trees) fail when they are not utilized, leading to atrophy visible as thinning cortex and enlarged ventricles on brain scans. Building reserve involves giving the brain novelty and engaging in activities like handwriting and reading.
Exercise Superiority and APOE4 Risk
Copied to clipboard!
(00:13:02)
  • Key Takeaway: Exercise is the most potent stimulus for brain health, with resistance training showing the greatest return on investment for preserving cognitive function and gray matter.
  • Summary: Resistance training, specifically lifting at 80% of one-rep max, releases myokines that signal the brain to promote neuron growth in the hippocampus, which is the first area affected by Alzheimer’s. The APOE4 gene is a major genetic risk factor, increasing risk 10-fold for men and up to 15-fold for women with two copies. The deadlift is cited as the single best exercise to protect the brain due to its full-body muscle recruitment.
Aerobic Zones and Heart Remodeling
Copied to clipboard!
(00:26:13)
  • Key Takeaway: Zone 5 training (90-95% max heart rate for 4 minutes) is superior for women’s brain health and cardiovascular remodeling compared to Zone 2 training alone.
  • Summary: Zone 5 training, which produces lactate as a fuel source for the brain, offers a greater return on investment for busy women than sustained Zone 2 jogging. A landmark study showed that four hours of rigorous exercise per week, including 20 minutes of Zone 5 work, reversed heart aging by 20 years in sedentary men aged 50, provided they started before age 65.
Blood Pressure, Leaky Brain, and Exercise Mix
Copied to clipboard!
(00:35:54)
  • Key Takeaway: Maintaining blood pressure below 135 systolic prevents the death of capillaries, which feed the brain and maintain the integrity of the blood-brain barrier.
  • Summary: Elevated blood pressure (hypertension over 135/85) kills the one-cell-thick capillaries, leading to a breakdown of the blood-brain barrier, known as a ’leaky brain.’ Aggressively managing blood pressure pharmacologically preserves gray matter, but exercise is the non-pharmacological solution. The optimal weekly exercise mix for cardiovascular health includes one session of 4x4 VO2 max training, one session of strength training, and two hours of moderate aerobic activity.
Alzheimer’s Death Mechanism and Ketones
Copied to clipboard!
(00:41:04)
  • Key Takeaway: Patients die from complications like asphyxiation due to loss of swallowing signals, not directly from Alzheimer’s, and a ketogenic diet is recommended post-diagnosis due to brain glucose utilization failure.
  • Summary: Once diagnosed, Alzheimer’s is irreversible, leading to death when the brain loses signals for vital functions like swallowing or balance. During the disease, the brain enters a metabolic crisis, losing its ability to effectively use glucose as fuel. A ketone-rich diet provides an alternative, more effectively utilized energy source for the compromised brain cells.
Menopause, Estrogen, and Brain Energy
Copied to clipboard!
(00:44:53)
  • Key Takeaway: The decline in estrogen during perimenopause causes a 30% reduction in brain glucose metabolism, leading to brain fog and forcing the brain to break down myelin for ketone production.
  • Summary: Women experience a 30% drop in brain glucose metabolism during perimenopause as estrogen levels decline, creating an energetic crisis in the brain. Estrogen is anabolic to muscle and bone, and its presence blocks the enzyme responsible for phosphorylating tau protein, thus preventing neurofibrillary tangles. Hormone Replacement Therapy (HRT) can support brain health by improving sleep (reducing amyloid buildup) and maintaining estrogen levels.
Amyloid, Tau, and Sleep Hygiene
Copied to clipboard!
(00:53:28)
  • Key Takeaway: Amyloid beta is an antimicrobial peptide cleared by the glymphatic system during deep sleep, and tau protein tangles form inside neurons when estrogen is low or stress is high.
  • Summary: Alzheimer’s pathology involves amyloid plaques (which are protective but accumulate due to poor sleep) and tau tangles (which collapse the neuron’s internal structure). Fragmented sleep, often caused by night sweats in menopause, prevents the glymphatic system from washing out amyloid beta. Sleep must be trained like a marathon, as one night of deprivation significantly raises amyloid risk, and this debt cannot be fully repaid later.
Sleep Optimization Supplements
Copied to clipboard!
(01:04:56)
  • Key Takeaway: GABA is recommended for trouble falling asleep due to a racing mind, while backloading starchy carbs at night aids sleep onset.
  • Summary: GABA (gamma aminobutyric acid) is suggested as a supplement to calm a racing mind by stabilizing thoughts. Eating starchy vegetables at night is beneficial for sleep regulation. Preparation for sleep should begin around 8 PM by avoiding work, hard conversations, and intense media to settle the nervous system.
Core Temperature and Sleep
Copied to clipboard!
(01:06:32)
  • Key Takeaway: Core body temperature must drop at least two degrees to fall and stay asleep, which can be aided by Glycine.
  • Summary: Sleep regulation requires a core body temperature drop of at least two degrees, achievable via temperature-controlled mattresses or cooling the room. Glycine is a supplement that aids sleep by helping to lower core body temperature and offers significant longevity benefits. Glycine’s role in temperature regulation is highlighted as a key mechanism for better sleep.
Adaptogens for Stress Management
Copied to clipboard!
(01:07:33)
  • Key Takeaway: Adaptogens like Ashwagandha and Rhodiola stabilize cortisol levels, adapting to the body’s needs by either lowering elevated cortisol or potentially raising low levels.
  • Summary: Ashwagandha and Rhodiola are adaptogens that help the body adapt to stress by stabilizing cortisol. They can be taken up to three times daily without causing fatigue and pair well with caffeine and theanine. This process aligns with circadian biology, mimicking the natural drop in light around 8 PM that triggers melatonin release.
Omega-3 Quality and Brain Health
Copied to clipboard!
(01:10:22)
  • Key Takeaway: Over 95% of popular US Omega-3 supplements tested were oxidized, necessitating strict sourcing, certification (like NSF), and refrigeration to maintain efficacy.
  • Summary: Omega-3 fatty acids are crucial as 70% of brain fat is DHA, supporting cell membrane fluidity necessary for synaptic transmission. Due to high oxidation rates in many brands, consumers must seek NSF-certified manufacturers and store the oil in the refrigerator immediately upon purchase. Omega-3s possess potent anti-inflammatory effects comparable to NSAIDs with no side effects.
Vitamin D and Cognitive Protection
Copied to clipboard!
(01:14:35)
  • Key Takeaway: Vitamin D deficiency increases all-cause dementia risk by 40%, while maintaining high levels (around 60 ng/dL) can lower Alzheimer’s risk by 80%.
  • Summary: Vitamin D receptors are abundant in brain areas like the hippocampus, which governs memory. A study on centenarians showed women who preserved cognitive function were not Vitamin D deficient. Maintaining optimal Vitamin D levels is strongly associated with significant risk reduction for Alzheimer’s disease.
Creatine’s Overlooked Brain Benefits
Copied to clipboard!
(01:15:35)
  • Key Takeaway: Creatine is a cheap, effective supplement that supports cell energy metabolism (ATP) and can reverse negative effects of sleep deprivation.
  • Summary: Standard 5g/day creatine dosing primarily saturates muscles, leaving insufficient amounts for the brain, suggesting higher doses (like 20g/day used in an Alzheimer’s pilot study) are needed for cognitive benefits. Creatine is protective against concussions and stroke, and high doses may reverse cognitive deficits from sleep deprivation. Concerns about kidney damage should be addressed by testing Cystatin C rather than relying solely on creatinine levels.
Creatine for Women and Quality Markers
Copied to clipboard!
(01:25:31)
  • Key Takeaway: Medium-dose creatine (1.5g/day) showed substantial mood and cognitive increases in perimenopausal women, expanding its exploration across the female lifespan.
  • Summary: A small study indicated that perimenopausal women supplementing with 1.5g of creatine daily experienced significant mood and cognitive improvements. When purchasing creatine, look for NSF certification and the ‘Creapure’ gold standard from Germany, which is gritty, unlike smoother, additive-laden alternatives. GI distress from creatine should prompt dose splitting rather than cessation.
Health Biomarkers and Cognitive Testing
Copied to clipboard!
(01:28:01)
  • Key Takeaway: Lipoprotein little A is a key hereditary marker for cardiovascular risk, and blood tests for P-tau217 and amyloid beta can now detect Alzheimer’s hallmarks with 90% PET scan accuracy.
  • Summary: Testing biological age every few months is recommended, alongside checking Lipoprotein little A for heart risk. New blood tests in the US can detect Alzheimer’s markers (tau protein, amyloid beta) with high accuracy, allowing for early intervention in mild cognitive impairment. Processing speed is tested by naming the color of a word, as the brain processes visual information 15 times faster than written words.
Neural Training Drills
Copied to clipboard!
(01:30:53)
  • Key Takeaway: Hand-eye coordination drills involving throwing a tennis ball while standing on one leg and wearing an eye patch significantly train executive functions and build cognitive reserve.
  • Summary: Five minutes daily of tennis ball drills, especially when adding an eye patch (blocking 50% vision) and standing on one leg, engages the visual cortex, cerebellum, and executive functions. This type of challenging activity strengthens neural networks and builds cognitive reserve by forcing the brain to adapt under load and stress. These drills were used with NBA players to decrease reaction time.
The Willpower Muscle and Growth
Copied to clipboard!
(01:36:58)
  • Key Takeaway: Growth in the anterior mid-cingulate cortex (AMCC), the ‘willpower muscle,’ is directly correlated with engaging in challenging activities, which predicts survival after major setbacks.
  • Summary: The AMCC is larger in ‘superagers’ and shrinks in sedentary individuals; its growth is triggered by resistance and challenge, such as forcing oneself to do something disliked like an ice bath. This area acts as a reserve for when life gets hard, and its size predicts long-term survival after health crises. Avoiding challenges creates a negative feedback loop where the brain stops doing hard things.
AI, Brain Rot, and Obsession
Copied to clipboard!
(01:44:14)
  • Key Takeaway: Over-reliance on tools like chatbots for thinking and scrolling for small dopamine hits contributes to ‘brain rot’ and a decline in cognitive ability and AMCC size.
  • Summary: The ease of using AI for tasks like calculation leads to a decline in personal cognitive skills, mirroring the atrophy of the AMCC when challenges are avoided. The constant pursuit of small dopamine hits from mindless scrolling trains the brain away from sustained focus required for reading or deep work. This self-inflicted decline contrasts with the neurobiological growth achieved through deliberate, hard mental effort.
Women’s Health Advocacy
Copied to clipboard!
(01:46:02)
  • Key Takeaway: The speaker’s passion stems from anger and frustration over societal pressures that cause women to downplay symptoms, leading to underrepresentation in literature and preventable diseases like Alzheimer’s (70% of cases) and autoimmune disorders (80% of cases).
  • Summary: Women are often socialized to prioritize family needs over their own health, leading them to hide symptoms or hesitate in seeking necessary medical advice. This systemic issue results in preventable diseases disproportionately affecting women, exemplified by the speaker’s grandmother who died from cancer after hiding her pain. Women deserve accurate health information and agency over their bodies, especially regarding issues like Hormone Replacement Therapy fears.
Defining Success and Faith
Copied to clipboard!
(01:55:45)
  • Key Takeaway: Ultimate success is defined as the ability to control one’s brain states—switching on focus (dopamine, norepinephrine) when needed and knowing how to switch off and recover.
  • Summary: The speaker defines success as achieving peak performance through mastery over brain states, referencing the concept of ‘Flow’ state. The speaker, a Christian, acknowledges that while science explains much, the complexity of neural development and survival after severe medical trauma suggests a higher, unseen power exists beyond current medical explanation. Witnessing severe brain deterioration in loved ones reinforces the urgency of preserving cognitive function.