Longevity is a fascinating topic that often leaves us wondering: What really matters more - our genes or how we live? The answer is not as straightforward as you might think. Scientists estimate that about 25% of how long we live is influenced by genetics. On the other hand, a whopping 75% is shaped by our lifestyle and environment.
This means that while our DNA lays the foundation, it is what we do with our lives that largely determines how long - and how well - we live.
How Genetics Shapes Longevity?
Let’s start with the basics: Our genes. They are like a blueprint that determines how our bodies function. From how efficiently we process nutrients to how resilient we are against diseases, your genetic makeup plays a crucial role.
But most of us don’t have “super genes” that guarantee a long life. Instead, genetics provides a starting point. Think of it as the hand of cards you are dealt in a game. How you play the game matters much more.
RDNE / Pexels / As we grow older, genetics tends to play a bigger role, especially past the age of 80.
That is when the body’s natural defenses begin to wear down, and genetic factors like resistance to age-related illnesses become critical. For instance, some people have genes that slow the progression of diseases like Alzheimer’s, keeping them healthy even in their golden years.
But for most of us, reaching that stage of life in good shape has less to do with genetics and more to do with how we live.
Why Lifestyle is the Key Player?
Lifestyle is the heavyweight champion when it comes to longevity. However, it is not just about eating your greens or exercising regularly (though those are huge). It is about the daily choices we make that either strengthen or weaken our bodies. Smoking, poor diet, lack of physical activity, and chronic stress are major culprits that can cut life short.
On the flip side, healthy habits can literally add years to your life.
Mikhail / Pexels / Studies show that maintaining a balanced diet rich in fruits, vegetables, whole grains, and lean proteins can drastically reduce the risk of chronic illnesses like heart disease and diabetes.
Similarly, regular exercise doesn’t just keep your heart healthy. It also keeps your mind sharp and your mood stable. Even something as simple as getting enough sleep or fostering meaningful social connections can significantly impact how long you live.
The First Eight Decades
During the first 80 years of life, lifestyle choices have a much bigger influence on longevity than genetics. If you eat poorly, avoid exercise, and ignore your mental health, no amount of good genes will save you from the consequences. Heart disease, obesity, and even some cancers are strongly linked to how we live, not what is written in our DNA.
Take smoking, for instance. A person with a genetic predisposition for long life can still cut their years short by indulging in harmful habits like smoking or excessive drinking. On the other hand, someone with a family history of heart disease can outlive their genetic odds by choosing a healthier lifestyle.
Beyond Eighty
As people age into their 80s and beyond, genetics begins to play a larger role. The body’s ability to repair itself diminishes, and inherited traits start to make a bigger difference. This is why some centenarians (people who live to 100 and beyond) often credit their long lives to “good genes.”
While their genetic resilience is certainly a factor, these individuals also tend to lead relatively healthy lives, suggesting that both factors work in tandem.
One fascinating discovery is that certain gene variations can protect against diseases like cancer or even slow down cellular aging. For example, the “longevity gene” FOXO3 is more common in people who live exceptionally long lives.
