Why Your Genes Don’t Tell the Whole Story
If one of your parents has dementia, it’s natural to wonder what that means for your own future.
Will it happen to you?
Is dementia inherited?
Are your genes your destiny?
These are some of the most common questions people ask as they begin thinking about their long-term brain health. The reassuring news is that, for most people, the answer is more nuanced than many realise.
Dementia is not a single disease. Alzheimer’s disease is the most common cause, but vascular disease, Lewy body disease and frontotemporal dementia each have different risk factors and biological mechanisms. A small proportion of Alzheimer’s disease is caused by rare inherited gene mutations that almost guarantee disease development, but these account for only a very small fraction of all Alzheimer’s cases.
While genetics can influence your risk, they are only one part of a much larger picture.
Understanding the role of genetics
Most cases of dementia are not directly inherited.
Although certain genes can increase the likelihood of developing conditions such as Alzheimer’s disease, carrying a genetic risk does not mean someone will inevitably develop dementia. Likewise, people with no known family history can still be diagnosed.
One of the most well-known genetic risk factors is the APOE-e4 gene variant, which has been linked to a higher risk of Alzheimer’s disease. However, it is considered a risk factor, not a diagnosis. Many people who carry the gene never develop dementia, while many who do develop Alzheimer’s do not carry it.
This distinction is important.
Genes may influence the cards you’re dealt—but they don’t determine how the game will be played.
Your environment writes the story
One area of research is epigenetics—the study of how lifestyle and environmental factors influence the way our genes behave.
While your DNA remains largely unchanged throughout life, the expression of your genes is continually shaped by your daily habits and environment.
Sleep.
Nutrition.
Exercise.
Stress.
Social connection.
Cognitive stimulation.
These factors influence the biological pathways that affect brain ageing, including inflammation, vascular health, metabolism and, in some cases, gene regulation.
A helpful way to think about it: your genes set a baseline, but your environment writes the story. Genes influence the possibilities. Your biology emerges from the ongoing conversation between your genes, your environment and the choices you make.
Supporting brain health throughout life
Brain health isn’t something to think about once memory changes begin.
It is something to nurture throughout life.
Many of the habits associated with healthy ageing are also widely recommended for supporting brain health as we get older. Regular physical activity, restorative sleep, cardiovascular fitness, a nutrient-rich diet, meaningful social connection, stress management and ongoing cognitive challenge all contribute to building what’s known as brain resilience.
Rather than focusing on a single intervention, the focus is increasingly on understanding the whole person.
You’re not a prisoner of your genes
Perhaps the most encouraging message emerging from this research is this:
Your future isn’t written by your DNA alone.
Your biology is dynamic.
Every decision you make—from how you recover to how you move, nourish yourself and manage stress—helps shape your long-term health.
Longevity isn’t something that simply happens to you.
It’s something you actively participate in.
The EIR LIV approach
At EIR LIV, we believe understanding your biology is the first step towards shaping your future.
Our approach combines diagnostics, lifestyle medicine, nutrition, cognitive performance, movement, recovery and personalised clinical guidance to help members better understand the factors influencing their long-term health.
Because while we can’t change the genes we inherit, we can better understand how they interact with the life we choose to live.
Your genes may set the baseline. But the story is still yours to write.
