Dementia Risk Reduction: The Evidence-Based 14-Factor Guide

Dementia is a growing concern worldwide, affecting millions of people each year. The statistics are stark: 2 in every 100 people between the ages of 65 and 69 have dementia, and the risk doubles every five years. By the time someone is over 90, that risk reaches 1 in 3 Alzheimer's Society.

But there is substantial reason for optimism. Research published in The Lancet has identified 14 modifiable risk factors that, together, could account for up to 45% of dementia cases worldwide — meaning that addressing them could substantially reduce the global burden of the disease The Lancet. These strategies are grounded in the latest scientific findings and offer practical steps that can be taken at any age. Crucially, many of these risk factors overlap and interact — improving one area often benefits others — making a comprehensive, lifestyle-level approach more powerful than targeting any single factor in isolation.

Below is a detailed breakdown of all 14 factors, the evidence behind each, and practical approaches that make a real difference at any stage of life.

The Power of Education and Cognitive Stimulation

Education is often seen as a tool for personal and professional development, but its benefits extend far beyond that. Lifelong learning and cognitive stimulation play a crucial role in building what scientists call "cognitive reserve" — the brain's capacity to resist damage from diseases like dementia by utilising alternative neural pathways and networks.

A landmark study involving over 107,000 people found that those with high cognitive stimulation at work had a lower risk of dementia compared to those with low cognitive stimulation. Interestingly, even those with limited formal education but high cognitive engagement at work reduced their dementia risk by 20%. For those with both high cognitive stimulation and high education, the risk was reduced by an impressive 37% The Lancet.

Cognitive reserve is thought to act as a buffer, allowing the brain to compensate for damage by utilising alternative neural pathways and networks. This reserve can be built and maintained through activities that challenge the mind — puzzles, learning new languages, playing musical instruments, and engaging in complex problem-solving tasks.

For adults, continuing education and pursuing hobbies that require mental effort can be particularly beneficial. Enrolling in online courses, participating in book clubs, or learning new skills like coding or photography all contribute to cognitive resilience. Staying mentally active through social interactions and volunteering can also provide cognitive benefits. Engaging in conversations, teaching others, or mentoring stimulates the brain and helps maintain cognitive function. The key is to keep the brain engaged and challenged, regardless of age.

Protecting Your Brain: The Importance of Hearing

Hearing is a critical sense that connects people to the world and plays a vital role in cognitive health. As we age, the risk of hearing loss increases — approximately 20% of people experience some degree of hearing impairment globally. Unfortunately, untreated hearing loss does not just impact communication; it also contributes significantly to cognitive decline.

A pivotal study found that untreated hearing loss is associated with up to a 2.4 times higher risk of developing dementia The Lancet. For every 10 decibels of hearing loss, the risk of dementia increases by 24% The Lancet.

The connection between hearing loss and dementia likely stems from several mechanisms. When hearing diminishes, the brain receives less auditory input, leading to changes in brain structure and function. Hearing loss also tends to lead to social isolation — itself an independent risk factor for cognitive decline.

The good news is that using hearing aids can significantly reduce the risk of cognitive decline. A systematic review found that people with hearing loss who used hearing aids had a lower risk of dementia compared to those who did not The Lancet.

Regular hearing check-ups are crucial, especially for older adults. Early detection and intervention can help mitigate the cognitive effects of hearing loss. Additionally, protecting hearing by avoiding prolonged exposure to loud noises, using ear protection in noisy environments, and maintaining good ear hygiene can prevent hearing loss from developing in the first place.

Vision Health and Dementia Risk

Just as hearing is vital for cognitive health, so too is vision. A major meta-analysis examining 14 studies involving over 6 million older adults found that those with vision loss had a 47% higher risk of developing dementia The Lancet.

Vision and cognitive health are closely intertwined. Visual impairment can lead to social isolation, depression, and a decrease in cognitive engagement — all of which contribute to dementia risk. Moreover, the brain regions responsible for processing visual information are also involved in other cognitive processes, making vision care an integral component of overall brain health.

Regular eye examinations are essential. Early detection of common conditions such as cataracts, glaucoma, and age-related macular degeneration (AMD) can prevent or delay vision loss. Treatment options including corrective lenses, medications, and surgery can restore or preserve vision, thereby reducing dementia risk.

In addition to regular check-ups, a diet rich in eye-friendly nutrients supports long-term eye health. Foods high in antioxidants — leafy green vegetables, carrots, and those providing omega-3 fatty acids — are particularly beneficial. Protecting eyes from harmful UV rays by wearing sunglasses and reducing screen time to prevent digital eye strain are also important preventive measures.

Furthermore, engaging in activities that stimulate both visual and cognitive functions — reading, puzzles, arts and crafts — can help maintain brain health by keeping the brain's visual processing centres active and engaged.

Mental Health Matters: Depression and Dementia

Depression is a significant risk factor for dementia that is frequently underestimated in discussions about cognitive health. Research shows that individuals with depression have more than double the risk of developing dementia compared to those without depression The Lancet. This risk is particularly pronounced in midlife, but it can affect individuals at any age.

The relationship between depression and dementia is complex. Chronic depression elevates levels of stress hormones like cortisol, which can damage the brain over time. Depression also tends to reduce social interaction and physical activity — both of which are critical for maintaining cognitive health.

Treating depression is crucial for reducing the risk of dementia. A variety of treatments are available, including antidepressant medications, psychotherapy, and lifestyle changes. Antidepressants can help regulate mood and cognitive function, while cognitive-behavioural therapy (CBT) provides tools to manage negative thought patterns and behaviours.

Lifestyle changes such as regular exercise, a healthy diet, and mindfulness practices like meditation can also alleviate symptoms of depression and improve overall mental health. Exercise in particular has well-established antidepressant effects by boosting endorphins and promoting neuroplasticity.

Social support is also a vital component of mental health. Building and maintaining strong relationships with family, friends, and community members can provide emotional support and reduce feelings of isolation and loneliness. Engaging in social activities, volunteering, or joining support groups can foster a sense of belonging and purpose.

Early intervention is key. If someone is experiencing symptoms of depression, seeking help from a healthcare provider promptly can not only improve quality of life but also reduce the long-term risk of dementia. Depression is highly treatable, and the earlier treatment begins, the better the outcomes — for both mental health and cognitive resilience over the decades ahead.

Exercise: Building and Protecting Brain Volume

Exercise is among the most powerful tools available for brain health. Regular physical activity has been shown to increase brain volume, enhance cognitive function, and reduce the risk of dementia The Lancet.

The benefits of exercise for the brain are multifaceted. Physical activity improves blood flow to the brain, delivering oxygen and nutrients that support neuronal health and function. Exercise also stimulates the release of neurotrophic factors — proteins that promote the growth and survival of neurons — enhancing brain plasticity and resilience.

Different types of exercise offer unique benefits for brain health. Aerobic exercises — walking, running, swimming, and cycling — are particularly effective at improving cardiovascular health, which is closely linked to brain health. Resistance training, such as weightlifting, helps build and maintain muscle mass, which supports overall health and mobility in older adults.

Yoga and tai chi are also beneficial for brain health, as they combine physical movement with mindfulness and relaxation. These practices help reduce stress and anxiety, improve balance and coordination, and promote mental clarity.

For most adults, the evidence supports aiming for at least 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous-intensity exercise per week, along with muscle-strengthening activities on two or more days. In addition to structured exercise, incorporating more movement throughout daily routines can make a significant impact. Simple actions like taking the stairs instead of the elevator, walking or cycling to work, and engaging in active hobbies like gardening or dancing all contribute to better brain health. Whether someone is 30 or 90, it is never too late to start reaping the cognitive benefits of physical activity.

Preventing Head Injuries: Safety First

Head injuries are a well-documented risk factor for dementia, particularly traumatic brain injuries (TBIs). A meta-analysis involving over 7 million people found that those who experienced a TBI had a 66% higher risk of developing dementia later in life The Lancet.

Even mild traumatic brain injuries — concussions — can have long-term effects on brain health. Repeated head injuries, often seen in contact sports like rugby, football, and boxing, are particularly concerning. These injuries can lead to Chronic Traumatic Encephalopathy (CTE), a neurodegenerative condition linked to cognitive decline and dementia.

Preventing head injuries is essential for protecting brain health. For athletes and individuals involved in high-risk activities, wearing appropriate protective gear such as helmets is crucial. Adhering to safety guidelines and rules in sports can also reduce the risk of injury.

For older adults, preventing falls deserves particular attention — falls are the leading cause of TBIs in this age group, often resulting in serious consequences. Implementing fall-prevention strategies such as removing tripping hazards from the home, installing grab bars in bathrooms, and ensuring adequate lighting can make a meaningful difference.

Engaging in balance and strength training exercises also helps prevent falls. Activities like yoga, tai chi, and targeted strength exercises improve balance, coordination, and muscle strength, reducing the likelihood of falls. Staying vigilant in everyday activities — biking, skiing, walking on icy sidewalks — and taking precautions to protect the head can help preserve cognitive health and reduce dementia risk over the long term.

The Impact of Smoking on Brain Health

Smoking is widely recognised as a major risk factor for cardiovascular disease, respiratory problems, and cancer, but its impact on brain health — and specifically its role in increasing dementia risk — is frequently underestimated.

A comprehensive 32-year study from the Whitehall II cohort revealed that current smokers had a significantly higher risk of dementia compared to those who never smoked. Importantly, ex-smokers did not carry an elevated risk — highlighting the brain benefit of quitting at any stage of life The Lancet.

The harmful effects of smoking on the brain are primarily driven by the chemicals in tobacco smoke, which cause oxidative stress and inflammation. These processes damage brain cells and contribute to the buildup of amyloid plaques and tau tangles — both hallmarks of Alzheimer's disease. Smoking also narrows blood vessels, reducing cerebral blood flow and increasing the risk of strokes and vascular dementia.

The good news is that quitting smoking can significantly reverse these risks. Within a few years of cessation, the body begins to repair the damage caused by smoking, including improvements in lung function, cardiovascular health, and blood circulation to the brain. Former smokers see a gradual decline in dementia risk over time, eventually approaching levels comparable to those who never smoked.

Quitting smoking is challenging, but numerous evidence-based resources and strategies can help. Nicotine replacement therapies (NRTs) — patches, gum, and lozenges — can ease withdrawal symptoms and cravings. Prescription medications such as varenicline (Chantix) and bupropion (Zyban) can also support cessation by reducing cravings and withdrawal symptoms. Behavioural support, including counselling and support groups, provides the motivation and practical tools needed to sustain cessation. Many healthcare providers offer smoking cessation programmes that combine medication with behavioural therapy, significantly improving quit rates.

LDL Cholesterol and Dementia: What You Need to Know

Recent research has clarified that elevated LDL (low-density lipoprotein) cholesterol raises dementia risk in a dose-dependent manner. A meta-analysis involving over a million people found that for every 1 mmol/L increase in LDL cholesterol, there was an 8% increase in the risk of developing dementia The Lancet.

Cholesterol plays a vital role in brain function — it is a key structural component of cell membranes and involved in the production of neurotransmitters. However, excess LDL builds up as plaques in the arteries supplying the brain, reducing blood flow and increasing the risk of stroke and vascular dementia. High LDL cholesterol is also associated with increased amyloid plaque formation in the brain, a characteristic feature of Alzheimer's disease; these plaques disrupt neuronal communication and trigger inflammatory responses that drive cognitive decline.

Managing cholesterol levels is therefore essential for reducing dementia risk. Statins — a class of cholesterol-lowering medications — have shown promise in reducing the risk of all-cause dementia and Alzheimer's disease when used consistently over time. However, statin use should be carefully monitored by a healthcare provider, as they can have side effects in some individuals. Statins are most effective when combined with lifestyle modifications rather than used in isolation.

Diet and lifestyle modifications play a significant and independent role. A heart-healthy diet emphasising fruits, vegetables, whole grains, and lean proteins can meaningfully reduce LDL cholesterol. The Mediterranean diet — rich in olive oil, legumes, fish, vegetables, and whole grains — has been associated with both lower cardiovascular risk and better cognitive outcomes in large observational studies. Incorporating healthy fats from olive oil, avocados, and nuts can further improve cholesterol profiles by raising HDL alongside lowering LDL. Limiting saturated fats found in processed meats and full-fat dairy reduces LDL more directly.

Regular aerobic exercise raises HDL ("good") cholesterol while lowering LDL. Maintaining a healthy weight and avoiding smoking are additional strategies for keeping cholesterol levels in check. Routine cholesterol screening — ideally starting in midlife — and a personalised management plan developed with a healthcare provider support early detection and sustained long-term control of this modifiable dementia risk factor.

Weight Management and Diabetes: Crucial Factors

Obesity and type 2 diabetes are two closely linked risk factors that significantly increase the likelihood of developing dementia. Central obesity — characterised by a larger waist circumference or higher waist-to-hip ratio — is particularly concerning, as it is closely tied to metabolic disturbances that affect brain health.

A study found that individuals with central obesity had a higher risk of cognitive impairment and dementia, especially those over 65. Even modest weight loss — as little as 2 kilograms — has been shown to improve cognition within six months The Lancet.

Obesity is also a major driver of type 2 diabetes, another condition strongly linked to dementia. Diabetes can lead to insulin resistance in the brain, impairing glucose metabolism and leading to the accumulation of toxic proteins associated with Alzheimer's disease. Research found that for every 5-year decrease in the age at which type 2 diabetes is diagnosed, the risk of developing dementia increases by 24% The Lancet.

Managing weight and diabetes is crucial for reducing dementia risk. A balanced diet that emphasises whole foods — fruits, vegetables, lean proteins, and whole grains — while limiting processed foods, sugary beverages, and refined carbohydrates, supports both healthy weight and blood sugar control. Incorporating regular physical activity is equally important: exercise improves insulin sensitivity and metabolic function. Aiming for at least 30 minutes of moderate-intensity exercise on most days, combined with strength training to build muscle and support metabolism, provides compounding benefit.

For individuals with diabetes, monitoring blood sugar levels and adhering to prescribed medications are key components of effective management. Working closely with a healthcare provider to develop a personalised diabetes management plan helps prevent complications and reduce the risk of cognitive decline. Stress management and adequate sleep also play an important role — both chronic stress and poor sleep disrupt metabolic processes and can contribute to weight gain and insulin resistance.

Blood Pressure Control: A Key to Brain Health

High blood pressure, or hypertension, is a significant and modifiable risk factor for dementia. It damages blood vessels in the brain, leading to reduced blood flow and increasing the risk of strokes and vascular dementia. A meta-analysis of 12 randomised controlled trials involving over 96,000 participants found that people who took antihypertensive medications had a lower risk of developing dementia or cognitive impairment compared to those who did not The Lancet.

One of the most significant studies in this area, the SPRINT trial, highlighted the importance of maintaining a systolic blood pressure of 120 mmHg or lower. The study found that individuals who maintained this target had a significant reduction in the risk of cardiovascular events and dementia The New England Journal of Medicine.

Managing blood pressure involves a combination of lifestyle changes and, for many people, medication. The DASH diet — rich in fruits, vegetables, whole grains, and low-fat dairy, and low in sodium — has strong evidence for lowering blood pressure. Reducing sodium intake, limiting alcohol consumption, and avoiding tobacco products are also critical steps. Regular aerobic exercise strengthens the heart and improves circulation, helping to lower blood pressure. Stress management techniques such as deep breathing, meditation, and yoga promote relaxation and reduce the body's stress response.

Medication is often necessary for individuals with hypertension to achieve and sustain optimal blood pressure control. Antihypertensive medications — including ACE inhibitors, beta-blockers, and diuretics — are commonly prescribed and should be taken as directed, with effectiveness monitored and treatment adjusted as needed. Routine home blood pressure monitoring allows early detection of changes and prompt intervention.

Alcohol Consumption: Balancing Risks

The relationship between alcohol consumption and brain health is complex. While moderate alcohol consumption has been associated with some health benefits in certain studies, excessive drinking is a well-established risk factor for cognitive decline and dementia.

Drinking more than 21 UK units of alcohol per week in midlife is associated with an increased risk of dementia. However, some studies suggest that light-to-moderate drinkers may have a lower risk of dementia compared to non-drinkers. This J-shaped curve, where light drinking appears to offer some protection, may not be as straightforward as it seems The Lancet.

The potential protective effects of alcohol — particularly from red wine — are often attributed to polyphenols such as resveratrol, which have antioxidant and anti-inflammatory properties. These compounds may help protect brain cells from damage and improve cardiovascular health, indirectly benefiting cognitive function.

However, the risks of excessive alcohol consumption far outweigh any potential benefits. Heavy drinking can lead to alcohol-related brain damage (ARBD), which includes a range of cognitive impairments resulting from prolonged alcohol use. Alcohol disrupts the balance of neurotransmitters, leading to mood disorders, memory problems, and impaired decision-making. Moreover, alcohol is metabolised to acetaldehyde — a toxic byproduct that damages brain cells — and chronic consumption raises the risk of liver disease, hypertension, and diabetes, all of which are independently linked to cognitive decline.

For those who choose to drink, moderation is key. Current UK guidelines recommend no more than 14 units per week for both men and women, spread evenly across the week with several alcohol-free days included. For those concerned about their alcohol intake or at risk for dementia, limiting or eliminating alcohol altogether is a prudent step. Non-alcoholic alternatives — sparkling water with juice, herbal teas, alcohol-free wines and beers — offer the same social experience without the health risks.

Social Connections and Mental Health

Social connections are vital for both mental and physical health. Strong social ties have been shown to reduce the risk of various health issues including cardiovascular disease, depression, and cognitive decline. Remaining socially active is one of the most effective strategies for reducing the risk of dementia.

Social interactions stimulate the brain by providing opportunities for communication, problem-solving, and emotional engagement. Meaningful relationships with family, friends, and community members help maintain cognitive functions and can protect against the effects of ageing on the brain The Lancet.

Loneliness and social isolation, by contrast, are linked to an increased risk of cognitive decline and dementia. Socially isolated individuals are more likely to experience depression, anxiety, and a decrease in cognitive engagement — all of which contribute to dementia risk.

Building and maintaining social connections requires deliberate effort. Joining clubs, volunteering, participating in community events, and staying in touch with family and friends are effective strategies. For those who are more introverted or have limited mobility, online communities and social media platforms offer alternative avenues for connection.

Maintaining social connections becomes increasingly important as people age, especially after retirement when social networks may naturally contract. Making a consistent effort to engage in activities that bring joy and foster relationships — scheduling regular calls with loved ones, joining a book club, participating in group exercise classes — compounds into meaningful cognitive protection over time.

For caregivers and family members of individuals with dementia, encouraging social interaction is crucial for their cognitive and emotional well-being. Group activities such as music therapy, art classes, and organised outings provide both cognitive stimulation and social support simultaneously. Strong social connections also provide emotional benefits — reducing stress and increasing feelings of happiness and fulfilment — that extend far beyond dementia prevention alone.

Reducing Exposure to Air Pollution

Air pollution is a growing public health concern, and its impact on brain health is becoming increasingly well-understood. Exposure to high levels of air pollution — particularly fine particulate matter (PM2.5) — has been linked to an increased risk of dementia. These tiny particles can penetrate the respiratory system, enter the bloodstream, and trigger inflammation and oxidative stress that damage brain cells The Lancet.

Air pollution is particularly harmful to older adults and individuals with pre-existing health conditions. Living in areas with high levels of traffic-related pollution or industrial emissions can significantly elevate the risk of cognitive decline. Studies have shown that individuals living in highly polluted areas have a higher incidence of dementia compared to those in cleaner environments.

On a personal level, practical steps include avoiding outdoor activities during high-pollution days, using air purifiers with HEPA filtration indoors, choosing exercise routes away from heavy traffic, and keeping windows closed when outdoor pollution is elevated. Reducing tobacco use indoors and limiting harsh chemical cleaning products further improves indoor air quality. For those who spend significant time in older buildings, checking for sources of indoor pollution — including mould, certain building materials, and gas appliances — can identify additional exposures worth addressing.

Advocating for cleaner environments through community initiatives and supporting policies that aim to reduce emissions can also make a significant difference. Transitioning to renewable energy sources, improving public transportation, and promoting electric vehicles are steps that reduce air pollution at a societal level. Many cities now offer real-time air quality monitoring and provide alerts when pollution levels are high — staying informed and timing outdoor activities around lower-pollution windows is a practical and accessible harm-reduction strategy for individuals in urban environments.

Emerging Factors and Future Strategies

As dementia research matures, additional modifiable factors are attracting sustained scientific attention. The 2024 Lancet Commission highlighted several emerging areas beyond the established 14 risk factors.

Sleep. There is growing evidence that both insufficient and excessive sleep may be linked to cognitive decline and dementia, though the science is not yet definitive The Lancet. Sleep plays a crucial role in brain health: it is during sleep that the brain clears out metabolic waste products — including amyloid — and consolidates memories. Disruptions in sleep patterns, such as sleep apnoea or chronic insomnia, can impair these processes and contribute to cognitive decline. Ensuring adequate, quality sleep is therefore an important consideration in any comprehensive brain health strategy.

Multivitamins and cognitive function. An important body of evidence has emerged around multivitamin and mineral supplementation. The COSMOS programme (COcoa Supplement and Multivitamin Outcomes Study) randomised 21,442 US adults aged 60 and over to a daily multivitamin versus placebo. A meta-analysis of three COSMOS cognitive substudies — involving 5,203 non-overlapping participants across COSMOS-Clinic, COSMOS-Mind, and COSMOS-Web — found that multivitamin supplementation significantly improved global cognition (mean difference 0.07 SD units, 95% CI 0.03–0.11, p=0.0009) and episodic memory (0.06 SD units, 95% CI 0.03–0.10, p=0.0007), equivalent to reducing cognitive ageing by approximately 2 years (Vyas et al., Am J Clin Nutr, 2024; doi:10.1016/j.ajcnut.2023.12.011). The nutrients associated with these cognitive benefits include choline, methylated B12, methylated folate, and the full B-complex. Research in this area continues to grow.

The gut-brain axis. Gut microbiome composition is gaining increasing attention as a potential contributor to brain health. The gut-brain axis — the bidirectional communication pathway between the gut and the brain — plays a role in regulating inflammation, immunity, and mood, all of which can impact cognitive function. Maintaining a healthy gut microbiome through a balanced diet rich in fibre, fermented foods, probiotics, and prebiotics may support brain health and reduce dementia risk. Research here is early-stage but growing rapidly.

Future directions. Looking ahead, neuroprotective pharmacological agents, gene therapy, and personalised medicine approaches are being explored as potential strategies to delay or prevent the onset of dementia. Early detection through biomarkers — such as blood-based amyloid and tau measures — and advanced imaging techniques could enable targeted interventions before clinically significant cognitive decline occurs, expanding the window for prevention considerably.

Conclusion: Taking Action Now

The 2024 Lancet Commission's analysis found that addressing the 14 modifiable risk factors described in this article could account for up to 45% of dementia cases worldwide. That figure represents a profound opportunity for individuals and for public health systems, particularly because most of these factors can be acted on at any age.

While earlier action yields larger benefit, meaningful risk reduction is achievable whether someone begins making changes in their 30s, 50s, or 70s. The breadth of the strategy matters: education and cognitive stimulation, hearing and vision care, mental health management, regular exercise, head injury prevention, smoking cessation, cholesterol management, weight and diabetes control, blood pressure management, alcohol moderation, social engagement, air quality, and attention to sleep all contribute independently and cumulatively.

These strategies are not solely about reducing dementia risk — they are about living a healthier, more capable life overall. Small, consistent changes in daily habits compound into significant improvements in cognitive function and general well-being over the years and decades ahead. The research is clear that no single strategy dominates; rather, the cumulative effect of acting across multiple risk factors simultaneously produces the greatest reduction in population-level dementia burden.

The journey to better brain health is a marathon, not a sprint. Building it incrementally — one change at a time, and gradually building on each success — is both the most sustainable and the most evidence-supported approach. No single intervention eliminates risk, but the cumulative impact of addressing multiple modifiable factors across a lifetime is substantial. The investment made in brain health today compounds over the years and decades to come, supporting not just a lower dementia risk but a sharper, more capable mind at every age.

References

1. Alzheimer's Society. Risk factors for dementia. Available at: https://www.alzheimers.org.uk/about-dementia/managing-the-risk-of-dementia/risk-factors-for-dementia
2. The Lancet. Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. Available at: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)01296-0/fulltext
3. SPRINT Study. A randomized trial of intensive versus standard blood-pressure control. New England Journal of Medicine. Available at: https://www.nejm.org/doi/full/10.1056/nejmoa1511939
4. Vyas CM, et al. Effect of multivitamin-mineral supplementation versus placebo on cognitive function: results from the clinic subcohort of the COSMOS randomized clinical trial and meta-analysis of three COSMOS cognitive substudies. Am J Clin Nutr. 2024. Available at: https://doi.org/10.1016/j.ajcnut.2023.12.011