You may have heard of the classic nature vs. nurture debate—the debate over whether your genetic makeup or your environment is the most important factor in forming your identity and character.
However, the emerging field of behavioral epigenetics research complicates this dichotomy by making it clear that genes and their expression are by no means set in stone. The way genes are expressed has the potential to vary significantly based on your experiences, behaviors, and other factors that you have far more control over than your genes themselves.
One of the areas where epigenetics has an enormous impact is on human longevity and life expectancy. You probably already know that there are many significant factors affecting life expectancy—including your genetic makeup, where you live, and your behaviors like diet and exercise—but you may not be aware that your environment and behaviors can interact with your genes to change how they’re expressed.
Keep reading as we provide an intro to the concept of epigenetics and begin to describe the complex relationship between epigenetics and human longevity.
What Is Epigenetics?
According to the experts at the CDC, epigenetics is defined as “the study of how your behaviors and environment can cause changes that affect the way your genes work.” Your behaviors and your environment can both affect your gene expression—which means that they can cause epigenetic alterations.
Genetics vs. Epigenetics
A comparison of epigenetics vs. genetics may help to clarify what the concept means. While genetic changes are typically permanent and irreversible, many epigenetic changes are reversible. In addition, while genetic changes are changes to DNA sequences, epigenetic changes are changes in how the body reads and expresses those DNA sequences.
What Is An Example of Epigenetics?
There are numerous examples of epigenetics, but we’ll start with a simple one to clarify the concept, focusing specifically on the effects of chronic stress.
Imagine there is a set of identical twins (we’ll call them “Andy” and “Bradley”) put up for adoption, and a different family adopts each twininto. Andy is adopted by a financially comfortable family, while Bradley is adopted by a family that ends up struggling with the effects of poverty. As a result, Andy has an easy childhood during which he experiences relatively little stress, while Bradley’s childhood is defined by chronic stress due to his family’s lack of resources. Over time, their differing stress levels trigger changes in their gene expression (i.e., epigenetic changes) without altering their underlying DNA. This also affects how their bodies respond to future stressors. The twins’ genomes are still identical, but their epigenomes are different because of the differences in their childhood stress levels. This stress (and resultant chronically elevated cortisol levels) could even cause Bradley to live a shorter life than Andy—this is part of why the richest American men live 15 years longer than the poorest, for example.
For more epigenetics examples, check out this article on the subject from LiveScience.
What Impact Does Epigenetics Have on Longevity?
Unsurprisingly, epigenetics and aging are strongly related—in other words, epigenetics plays a crucial role in shaping our longevity. We’ll explain what that means and how we know that.
Epigenetics of Aging and Longevity
Emerging research suggests epigenetic changes can impact longevity by regulating genes associated with crucial bodily functions like cellular repair, immune response, and disease resistance.
According to a comprehensive review of the epigenetic literature:
- Our lifespan is not genetically predetermined, but instead, primarily epigenetically determined. This means that when it comes to lifespan, nurture takes precedence over nature.
- Environmental and behavioral influences like diet and exercise can alter our lifespan by altering our epigenome.
- Inhibitors of epigenetic enzymes can influence the lifespan of model organisms like mice and fruit flies.
Reversible Environmental and Behavioral Alterations of the Genome
Epigenetic mechanisms regulating longevity and aging are incredibly complex, which means there’s quite a bit left to discover in this relatively new field. However, what we’ve learned so far about epigenetics across the human lifespan is immensely promising—especially when it comes to our own environmental and behavioral influence over our longevity.
Are You Ready to Lean into Life Expectancy?
Using cutting-edge research and data, the Life Expectancy Calculator team creates highly accurate models that make it easy to discover your own life expectancy. If you’re curious how your environment and behaviors may have impacted your own life expectancy, give the Life Expectancy Calculator a try today.
And please stay tuned for further educational blog posts (“Life Lessons”) on the fascinating phenomenon that is longevity!
