Chronological Age vs. Biological Age: Why Do We Age?

Chronological Age vs. Biological Age: Why Do We Age?

Quick overview of what we’ll cover in this blog post:

  • What affects aging
  • Chronological age vs biological age
  • What affects our biological age
  • How we can turn back the clock

It’s the most fundamental question anyone could ask, and arguably the reason that drives much of science: why do we age? Though science and healthcare has largely focused on the aftereffects of aging, such as disease, research has begun to reveal the true answer to this question, which has become the central focus of the worldwide longevity movement. Now, researchers can finally provide a clear response.

Why do we age?

Aging is a multifaceted phenomenon influenced by an intricate interplay of genetic, environmental, and lifestyle factors. While the inevitability of aging was once thought of as a universal truth, scientists have begun to reveal the mechanisms of aging that we now call the 9 hallmarks of aging. With this revelation came the realization that our chronological age may not always match up with our biological age.

What’s our chronological age?

Our chronological age is simply the number of years we’ve been alive since birth. When people ask us how old we are, we respond with our chronological age. However, the mere passage of time doesn’t tell the full story of aging, and therein lies the dilemma.

Imagine a married couple that are both 60 years old. While one spent their life watching what they eat, sleeping well, getting plenty of exercise, and going to the doctor regularly, the other mostly relaxed and stayed at home. Despite sharing the same chronological age, these individuals probably exhibit vastly different levels of health and vitality. In other words, they have different biological ages.

What’s our biological age?

In contrast to chronological age, biological age reflects the actual condition of an individual’s body at the cellular and molecular levels. This nuanced metric considers factors such as the integrity of DNA, cellular function, and the efficiency of organ systems – not to mention the risk of age-related disease.

Understanding biological age provides a more accurate glimpse into an individual’s health status, offering insights into the aging process. Though it’s impossible to determine our biological age from a glance, there are still simple steps we can take to reveal our biological age, such as a lab-based or at-home blood test, or even a saliva test. If you have recent results from a blood test already, you can also use our free biological age calculator to determine your biological age.

What goes into our biological age?

The Role of Genetics

Our genes dictate the blueprint of our biological systems, influencing how efficiently our cells repair damage, combat oxidative stress, and regulate essential processes. Some individuals may possess genetic variants that confer resilience against aging, while others may be genetically predisposed to age-related challenges.

Genetics was once believed to play the most important role in the aging process. But research has revealed that genetics may only influence about 25% of how we age, and genetics alone can’t answer the question, “why do we age?” Genomic instability is still one of the hallmarks of aging, but our environment may play a larger role.

Environmental Influences

Beyond genetics, the environment in which we live exerts a profound impact on the aging process. Some may imagine environmental factors as just exposure to pollutants or even how we grew up. But environmental factors also include diet, exercise, sleep, and stress levels, all of which contribute to the intricate dance between our genes and the environment. Adopting a healthy lifestyle can mitigate the effects of aging, promoting cellular resilience and delaying the onset of age-related conditions.

Oxidative Stress & Cellular Aging

One of the key players in biological aging is oxidative stress, a byproduct of cellular metabolism. Free radicals, highly reactive molecules generated during metabolic processes, can damage cellular components such as DNA, proteins, and lipids. Over time, oxidative stress contributes to cellular aging and the onset of age-related diseases. Antioxidants, found in certain foods and supplements, play a crucial role in neutralizing free radicals and mitigating the impact of oxidative stress.

Telomeres: The Cellular Hourglass

Telomeres also play an important role in biological aging, acting almost like a cellular hourglass, telling us when the end of a telomere’s cycle is near. These protective caps at the ends of chromosomes safeguard genetic information during cell division. However, with each cell division, telomeres gradually shorten until they reach a critical length, signaling the onset of aging.

In the question of chronological age vs biological age, it’s clear that one doesn’t always match the other: sometimes our chronological age is years ahead of our biological age, and sometimes it’s the opposite. But by focusing on our biological age, we can attack many of the underlying processes behind aging, and potentially slow or even reverse our biological age. Our free longevity quiz can help you identify opportunities to improve your biological age so you can focus your efforts on enjoying a longer, healthier life.

Note: The above statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.