Brain Health Through the Seasons: What We Can Control About Alzheimer's Risk

Margaret arrived at my office with a list of questions. Her mother had just been diagnosed with Alzheimer's at 78. Her aunt had it too. "Dr. Wong," she asked, her voice tight with worry, "am I next? Is there anything I can actually do?"

I looked at the 52-year-old woman across from me—active, engaged, clearly taking good care of herself—and I gave her an answer I couldn't have given twenty years ago. "Yes," I said. "There's quite a lot you can do."

December brings us to the close of another year, a time when many people reflect on their health and make resolutions for the future. This month, I want to share what we now know about Alzheimer's risk and prevention—knowledge that represents one of the most hopeful developments in geriatric medicine over the past two decades.

The question "Will I get Alzheimer's?" used to haunt people without any good answers. Today, science gives us a much better understanding of risk factors, and more importantly, what we can actually do about them.

Understanding Your Risk Profile

One in nine people age 65 and older develops Alzheimer's disease. Pooling data from hundreds of thousands of people worldwide, scientists have identified six practical risk factors that are common, easy to identify, and useful for assessment.

The strongest factor we can't control is family history. Risk increases significantly if a parent or sibling has been diagnosed with Alzheimer's or dementia.

Two factors relate directly to brain function: hearing loss (acquired, not lifelong) and limited education (fewer than 12 years of formal schooling).

Three factors relate to overall health: hypertension, diabetes, and low physical activity (less than 150 minutes per week of moderate exercise).

Understanding your personal risk profile matters because it changes how you approach brain health. Zero risk factors doesn't mean zero risk, but multiple factors can mean symptoms start years earlier. The key is knowing where you stand so you can focus on what's actually modifiable.

The Heart-Brain Connection

Brain cells need a constant flow of oxygen and nutrients delivered through tiny blood vessels. When those vessels don't deliver what brain cells need, cell function suffers and damage accumulates. This is why hypertension, diabetes, and physical inactivity are major Alzheimer's risk factors.

Every time you exercise, control your blood pressure, manage your blood sugar, or quit smoking, you're not just protecting your heart. You're protecting your brain's ability to function for years and decades from now.

Heart health and brain health aren't separate, they're connected. What's good for your cardiovascular system is good for your cognitive future.

Sleep: Your Brain's Nightly Tune-Up

People who regularly sleep fewer than five hours per night may face about twice the risk of dementia compared to those who get six to eight hours. Understanding "twice the risk": People with no major risk factors have a lifetime risk of about 10%. People with twice the risk have a lifetime risk of 20%.

Think of sleep as your brain's nightly tune-up. One thing the brain does during sleep is clear out waste materials, including amyloid-β, a protein that builds up in Alzheimer's disease. When sleep is disrupted, this cleaning process doesn't work as well.

Sleep difficulties are common in later life, but that doesn't mean they're inevitable or untreatable. Making good sleep a priority is one of the most practical steps you can take for long-term brain health.

The Power of Connection

Moderate to severe hearing loss at midlife is one of the strongest modifiable risk factors for Alzheimer's disease. But the risk isn't about the hearing loss itself—it's about what happens next.

When left untreated, hearing loss leads to less conversation, reduced mental stimulation, and fewer social activities. This creates a cascade: hearing loss can lead to social isolation, which carries about 1.5 to 1.6 times higher dementia risk compared to peers who stay socially engaged.

Here's the encouraging part: when hearing loss is effectively treated with hearing aids or other interventions, the risk decreases. A major recent study found this. Treatment appears to interrupt the cascade.

This isn't just about fixing a sensory problem. It's about maintaining the cognitive stimulation and social engagement that keep brains resilient. Every conversation matters. Every social connection counts.

If you or someone you love is struggling with hearing, don't dismiss it as "just part of aging." Get it evaluated. Get it treated. Stay connected to the world around you.

Cognitive Reserve: The Oak Tree Analogy

Why are limited education, low physical activity, and lack of social connection risk factors for Alzheimer's? The answer lies in understanding cognitive reserve.

Imagine two oak trees, each with the potential to live for a century. One grows in rich soil with steady rain, sunlight, and shelter. Its roots spread deep, and its trunk grows thick and strong. The other grows in thinner soil with less water and more storms. It survives, but its trunk is slimmer and its roots shallower.

Decades later, both face oak wilt disease. The well-nourished tree, with its strong roots and thick bark, can resist infection longer. The tree that grew under harsher conditions shows signs of disease earlier and declines more quickly.

Brains work similarly. People who have opportunities for education, engaging work, strong social ties, and lifelong learning build stronger networks in the brain. Like the well-nourished tree, these brains can better withstand Alzheimer's disease changes, so symptoms appear later.

Every conversation, every challenge, every new skill strengthens the brain's resilience against future decline.

What About Genetics?

Scientists estimate that between 40 and 70 percent of Alzheimer's risk is influenced by genetic factors. That sounds overwhelming until you flip it around: 30 to 60 percent of risk is not genetic.

About one in four people carries at least one copy of the APOE ε4 variant, which increases risk two to three times. A smaller group inherits two copies, raising the risk tenfold or more. But even in this high-risk group, Alzheimer's isn't inevitable. Some people live into their 90s without symptoms.

What can you control? Physical activity, cardiovascular health, social engagement, cognitive stimulation, hearing treatment, sleep quality, diet, alcohol consumption, and smoking cessation. Each one individually makes a difference. Together, they can substantially shift your risk trajectory.

You can't change your genes, but you can change how those genes express themselves through the life you live. Every healthy choice matters. Every risk factor you address counts. Every positive change builds protection, regardless of what your DNA says.

Brain Health Through the Holiday Season

The holidays can disrupt healthy routines, but maintaining brain-protective behaviors during busy seasons matters more than perfection.

Keep moving: Even 20-minute walks count toward the 150 minutes weekly that reduce Alzheimer's risk. Holiday shopping, decorating, and activities all contribute to physical activity.

Prioritize sleep: Stick to regular sleep and wake times when possible. Limit alcohol, which disrupts sleep quality even when it seems to help you fall asleep initially.

Stay connected: Holiday gatherings provide exactly the kind of social engagement that protects brain health. Even difficult family dynamics provide cognitive stimulation. Virtual connections count too when distance separates families.

Manage stress: Chronic stress increases inflammation in the brain. Build in quiet moments. Say no to some obligations. Practice whatever stress management works for you.

Eat reasonably well: Perfect nutrition isn't realistic during holidays, but mostly healthy choices with occasional treats provide better brain protection than extreme restriction followed by indulgence.

The holidays don't have to be perfect for brain health. They just need to be reasonably balanced.

The GOLD Approach to Brain Health

As we close out another year, it's worth reflecting on how far Alzheimer's prevention science has come. Twenty years ago, the answer to "Will I get Alzheimer's?" was simply "Risk increases with age." That wasn't particularly helpful.

Today, we can identify specific, measurable risk factors. We understand how they interact and compound each other. We know which ones are modifiable and which aren't. We have evidence that lifestyle interventions actually make a difference.

Gradual, consistent changes that build over time. You don't need perfection—you need persistence.

Open awareness of your personal risk factors. Understanding your profile helps you focus efforts where they'll make the most difference.

Lifelong learning and engagement. Keep your brain stimulated through conversation, challenge, and connection.

Daily choices that protect cardiovascular health, support good sleep, maintain social ties, and reduce inflammation.

We still don't have all the answers. Genetics matter significantly. Much remains unknown about why some people develop Alzheimer's while others don't.

But we know infinitely more than we once did. That knowledge is power—power to make informed choices about modifiable risk factors.

Margaret's Journey

Remember Margaret, who came to my office worried about her family history? We talked through her risk factors. She had several working in her favor: excellent cardiovascular health, strong social connections, and ongoing mental stimulation through her work. She also had one significant concern: she'd been sleeping poorly for years.

We addressed the sleep issue. She started regular exercise, which improved both her sleep and her cardiovascular health even more. She got her hearing checked and committed to regular monitoring. Most importantly, she stopped living in fear of an inevitable diagnosis and started living intentionally to protect her brain health.

Two years later, Margaret tells me she feels more in control of her health than she ever has. She's not guaranteed to avoid Alzheimer's—none of us are. But she's doing everything within her power to shift the odds in her favor. That's not just smart medicine. That's taking charge of your future.

As we enter a new year, consider what you can do for your own brain health. Small changes matter. Consistent efforts compound over time. Every positive choice builds protection.

Your brain's future isn't entirely in your hands, but more of it is than you might think. That's a reason for hope as we look toward the year ahead.

Warmest Aloha,

Dr. Warren Wong

PS: I say it over and over again: There's no one more important than the caregiver in the daily life of a frail person.