Last week, I reviewed the 2026 WHO Guidelines for Dementia Prevention, a 140-page document that suggests up to 45% of dementia risk may be preventable.
In that review, I distilled dementia prevention down to three core principles:
- Heart health = brain health
- Keep your brain connected and challenged
- Build brain health into your daily routine
Those are important foundations. But this week, I want to highlight several areas where I believe the WHO guidelines fall short—particularly when we move from population-level recommendations to individualized care.
This is a common challenge I see in medical research. What is beneficial—or not beneficial—for a population isn’t necessarily true for every individual.
We need population-level studies. They help us identify powerful levers that can affect health across hundreds of thousands or even millions of people. But as a physician, I care for the person sitting in front of me. My job is to determine which research actually applies to that individual and which health factors deserve the most attention.
For example, a study conducted primarily in East Asian women may not necessarily tell us what is most relevant for a white male patient sitting in my office.
So, what areas of dementia prevention do I believe deserve more individualized attention?
- Targeted supplementation and nutrient deficiencies
- Menopause hormone therapy for certain women
- Sleep apnea as a risk factor for dementia
Insufficient Nutrients for the Brain Are Widespread
The WHO does not outright discredit supplementation. Rather, it concludes that there isn’t enough evidence to recommend widespread supplementation specifically for dementia prevention.
I understand the sentiment: don’t take something unless you need it.
However, based on my experience evaluating hundreds of extensive laboratory panels each year, more than 90% of my patients have a deficiency or insufficiency in at least one nutrient that can be relevant to brain health, including:
- Vitamin B12
- Vitamin B9 (folate)
- Vitamin D
- Omega-3 fatty acids
I’ve previously written about the VitaCog and OmegaAD studies and the potential role of optimizing B vitamins and omega-3s in reducing dementia-related risk. That makes me particularly interested in identifying possible nutrient insufficiencies rather than assuming that most people are adequately nourished.
The COSMOS trial also found that daily multivitamin use was associated with slower cognitive aging in older adults.
Of course, supplementation isn’t a substitute for a healthy diet, and more isn’t necessarily better. The goal should be to identify and address individual deficiencies or insufficiencies when they exist.
Even people who eat relatively healthy diets can develop important nutrient gaps because of food choices, absorption issues, medications, genetics, or aging.
For that reason, I believe individualized assessment of nutritional status deserves a place in a comprehensive approach to brain health and dementia prevention.
Menopause Hormone Therapy and Dementia
First, I want to be very clear: we do not currently have robust clinical evidence showing that menopause hormone therapy (MHT) prevents dementia.
But I also believe this is an area that deserves more attention when we talk about women’s brain health.
Consider a few important facts:
- Approximately two-thirds of people living with dementia are women.
- Earlier menopause has been associated with a higher risk of dementia.
- Menopause is associated with measurable changes in the brain.
- Symptoms such as brain fog, sleep disruption, hot flashes, and night sweats can significantly affect cognitive function and quality of life.
The loss of estrogen during menopause clearly affects the brain and overall cognitive function. For some women, appropriate MHT can improve menopausal symptoms and may influence aspects of brain structure and function.
And there is another piece we shouldn’t overlook.
Severe menopausal symptoms can lead to poor sleep, reduced social engagement, less physical activity, and reduced cognitive stimulation—all factors that can potentially compound other dementia risk factors.
The evidence is still evolving. However, a 2023 meta-analysis found a signal suggesting a potential benefit of MHT on dementia risk, particularly when therapy is initiated earlier in the menopausal transition.
This concept is sometimes referred to as the “critical window” hypothesis: the idea that the timing of hormone therapy may matter, with potential benefits being greater when treatment is initiated closer to the onset of menopause.
That doesn’t mean MHT is right for every woman, nor does it mean it should be prescribed specifically to prevent dementia. It does mean that menopause and brain health deserve to be considered together when evaluating an individual woman’s risk factors and treatment options.
Sleep Apnea Hurts the Brain
The WHO guidelines appropriately emphasize the importance of sleep, but I was surprised by how little attention they gave to sleep apnea and dementia risk.
A recent meta-analysis found that obstructive sleep apnea was associated with an approximately 34% higher risk of dementia.
Sleep apnea is an increasingly common condition in which the airway repeatedly becomes blocked during sleep. These interruptions can cause drops in blood oxygen, fragmented sleep, and repeated stress responses—all of which can affect the brain.
And this isn’t simply about feeling tired the next day.
Sleep is an important time for the brain to recover and perform essential maintenance. Chronic sleep disruption may interfere with these processes while also contributing to other dementia risk factors, including insulin resistance, elevated blood pressure, vascular dysfunction, and increased nervous system activation.
It’s a compounding problem.
Could You Have Sleep Apnea?
Common symptoms of sleep apnea include:
- Loud or disruptive snoring
- Witnessed pauses in breathing during sleep
- Gasping or choking during the night
- Morning headaches
- Frequent nighttime urination
- Waking repeatedly throughout the night without an obvious reason
- Excessive daytime sleepiness or fatigue
- Problems with concentration, memory, or mood
Sleep apnea is often associated with obesity, but it is important to understand that you don’t have to be overweight to have sleep apnea.
I regularly see lean, fit individuals with significant symptoms who test positive on a home sleep study.
Fortunately, evaluating for sleep apnea has become much easier. Home sleep studies are widely available and can be a convenient first step for many people. They aren’t perfect, and some people will require a more comprehensive sleep evaluation, but they can identify many common cases of sleep apnea.
If you have symptoms, it’s worth talking with your healthcare provider about whether testing makes sense for you.
The WHO Guidelines Are Great. And They Could Be Better.
Population-level guidelines are incredibly valuable. They help us understand what works on average.
But medicine isn’t practiced on an average person.
An individual patient may have elevated homocysteine, low omega-3 status, premature menopause, untreated sleep apnea, an APOE4 genetic variant, insulin resistance, hypertension, or another potentially modifiable vulnerability that never rises to the level of a population-wide recommendation.
That’s where individualized brain health becomes so important.
We still don’t fully understand what causes dementia, and there is no single test or intervention that can guarantee prevention. But we are fortunate to live in a time when we understand more about dementia risk factors than ever before.
If you’re serious about protecting your brain as you age, don’t just ask, “What does the population data say?”
Ask: “What does my individual risk profile tell me?”
That may mean looking at your cardiovascular health, nutrition, sleep, hormones, metabolic health, genetics, activity level, social connections, and other factors that can influence brain health.
Start by identifying your strengths and your gaps. Consider appropriate laboratory testing and screening. And work with a healthcare provider who takes a comprehensive, individualized approach to brain health.
Dementia prevention isn’t about finding one magic intervention. It’s about identifying the factors that matter most for you—and addressing the ones you can change.
If you’re in Asheville, NC, and interested in taking a more individualized approach to brain health, talk with your healthcare provider about your personal dementia risk factors and which assessments may be appropriate for you.