Preventing Dementia: Protecting Brain Health and Longevity

Motor Neurone Disease (MND), also known as amyotrophic lateral sclerosis, Parkinson’s disease and Alzheimer’s disease, the most common cause of dementia, are all forms of neurodegeneration.

Modern medicine has transformed the treatment of many major illnesses. Heart disease, diabetes and cancer now have increasingly effective interventions that improve both lifespan and quality of life. Unfortunately, this is not yet the case for most neurodegenerative diseases. Treatments remain limited and largely symptomatic. For this reason, prevention remains central to any meaningful dementia strategy.

At OT&P in Hong Kong, dementia prevention forms part of a broader longevity and healthspan programme, focusing on modifiable risk factors and long term brain resilience.

Importantly, dementia is not purely genetically determined. Even the widely discussed APOE4 gene is a risk factor rather than a diagnosis. When dementia appears to run in families, shared lifestyle and environmental influences often play a significant role. This distinction is empowering. It means risk can often be reduced.

How Much of Dementia Is Preventable?

Major international reviews suggest that approximately 40 to 45 per cent of dementia cases may be attributable to modifiable risk factors, including physical inactivity, poor diet, hypertension, diabetes, smoking, hearing loss, depression and social isolation. This estimate comes from the 2020 and 2024 Lancet Commission reports on dementia prevention, intervention and care.

Some authors argue the proportion may be higher when broader metabolic and lifestyle factors are considered. Dr Tommy Wood, in his recent book The Stimulated Mind: Future‑Proof Your Brain from Dementia and Stay Sharp at Any Age, suggests that between 45 and 70 per cent of dementia risk may be preventable through sustained behavioural and environmental change.

While precise percentages remain debated, the direction of evidence is clear. A substantial proportion of dementia risk is modifiable.

Dr Wood proposes a “three S model” for brain health: stimulation, sleep and nutrient supply. These principles align closely with a functional and preventative approach to medicine.

There appears to be a “use it or lose it” component to cognitive capacity. Research shows that individuals engaged in complex, intellectually demanding work or hobbies such as reading, writing, learning languages, music, dance or creative arts tend to experience slower cognitive decline and lower dementia risk. In contrast, highly routinised and unstimulating lifestyles are associated with a more rapid decline.

Key Levers for Dementia Prevention

Cognitive stimulation

Learning new and challenging skills, particularly those requiring sustained attention and social interaction, may help build cognitive reserve and resilience. Music, languages, artistic pursuits and complex hobbies create neurological demand that supports long term brain function.

Physical training

Regular movement, particularly cardiovascular exercise, improves cerebral blood flow, oxygen delivery and metabolic health. Physical activity is one of the most consistently supported interventions in dementia risk reduction.

Sleep optimisation

High quality sleep supports memory consolidation and metabolic regulation. Emerging research also highlights the importance of sleep in the clearance of metabolic waste products from the brain. Wearable devices now allow practical monitoring of sleep duration and quality, helping individuals identify patterns that require attention.

Stress regulation

Chronic stress negatively affects cognitive performance and metabolic health. Techniques such as structured breathing exercises, visualisation, defined routines and emotional regulation strategies may help maintain cognitive function under pressure.

Nutrient Supply and Brain Metabolism

The brain requires structural building blocks, micronutrients and a stable metabolic environment. A nutrient dense diet forms the foundation. This typically includes seafood, meat, modest amounts of organ meats, eggs, high fibre plant foods, nuts, seeds and minimally processed carbohydrates, while limiting ultra processed foods and excess simple sugars.

Supplements may be used selectively where clear deficiencies or increased requirements are identified, but they should not replace dietary quality.

A Longevity Approach to Brain Health

Many individuals already following a healthspan or longevity programme will be attentive to diet and exercise. What is often underestimated is the power of deliberate cognitive challenge. Learning a new language, taking up dance, or mastering a musical instrument is not simply recreational. It may represent a meaningful intervention in long term brain health.

For patients in Hong Kong and internationally, dementia prevention should be viewed as a proactive, lifelong strategy rather than a reactive response to memory loss. While no intervention offers absolute certainty, a structured approach combining cognitive stimulation, physical training, restorative sleep and nutritional optimisation can substantially reduce risk.

Prevention remains our most powerful tool in the fight against dementia.

Dr Tim Trodd

Family Medicine, Functional Medicine, General Practice

MBBS (London)
DCH (London)
DRCOG (UK)
MRCGP (UK)
FHKAM (Family Medicine)

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References

Livingston, G. et al., 2020. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. The Lancet, 396(10248), pp.413–446.
Livingston, G. et al., 2024. Dementia prevention, intervention, and care: 2024 update of the Lancet Commission. The Lancet.
World Health Organization, 2019. Risk reduction of cognitive decline and dementia: WHO guidelines. Geneva: WHO.
Wood, T., 2024. The Stimulated Mind: Future‑Proof Your Brain from Dementia and Stay Sharp at Any Age.