in Opinion
Do biological age tests justify their cost?
Imagine discovering your body is biologically five years older than your chronological age. You maintain a regular exercise routine, achieve adequate sleep, consume wholesome meals, and lead a fulfilling personal life. What misstep have you taken? Can such a test be deemed reliable?
Numerous companies are promoting products that claim to reveal an individual’s “actual” biological age—essentially, how effectively your body is functioning—for prices ranging from approximately US$30 to over $1,000. These offerings are founded on epigenetic aging clocks, which serve as research instruments to estimate age based on a person’s DNA. These clocks are fundamentally altering how scientists investigate aging and how the general public perceives it.
However, while epigenetic clocks are highly effective research instruments for studying aging across populations, they are not designed to provide definitive pronouncements on individual health statuses.
We are biobehavioral health scientists dedicated to understanding how early life development and environmental influences throughout a person’s life shape biological aging, thereby impacting health and disease trajectories decades later. As researchers who utilize epigenetic clocks in our work, we have found them to be exceptionally informative tools when examining large cohorts. Yet, these clocks can yield inaccurate results at the individual level and do not meet the rigorous standards mandated for common medical assessments.
What are epigenetic clocks?
The measurement of reversible chemical modifications to DNA, referred to as epigenetic marks, can offer insights into the aging process of your body.
By analyzing DNA acquired from standard blood draws, researchers can quantify millions of these epigenetic marks within an individual. Applying statistical algorithms to this data can generate a singular value representing that person’s epigenetic age, serving as a parallel to chronological age.
Epigenetic clocks function because the chemical marks on DNA are subject to change over time and are influenced by factors such as lifestyle, stress, and environmental conditions. These alterations capture aspects of aging that chronological age alone might not fully represent.
In this manner, epigenetic clocks assist scientists in pinpointing the experiences, exposures, and behaviors that have the potential to accelerate or decelerate biological aging.
Epigenetics: Can we change our genes? – BBC World Service – YouTube
Watch On Not suitable for individual health decisions
Why are epigenetic clocks unable to provide dependable results regarding biological age for individual persons?
Firstly, there exist numerous distinct categories of epigenetic clocks, each formulated for a particular objective. Some are employed to forecast an individual’s age, while others are utilized to predict the rate at which someone is aging or the remaining years of their life. These differing clocks do not consistently align, even when applied to the same individual.
Secondly, epigenetic modifications are inherently dynamic, rendering age predictions susceptible to transient shifts in diet, environmental exposures, illness, time of day, and other temporary influences. Consequently, the estimated age could exhibit considerable variation depending on the timing of an individual’s test.
Thirdly, the creation of epigenetic clocks presents significant technical challenges, and there is no universally accepted gold-standard methodology for developing these clocks across different laboratories. For instance, assessing epigenetic age using saliva versus blood samples can produce markedly different outcomes for the same individual. The technologies used to detect epigenetic marks have also advanced over time and are likely to continue improving. As these methodologies evolve, the original algorithms designed for specific measurement platforms may not function identically.
There isn’t always consensus among experts on the definition of aging, largely because it is an incredibly intricate process. Condensing this complexity into a single numerical value, such as an epigenetic age, can be misleading.
(Image credit: Elena Pejchinova via Getty Images)
Fourth, there is no widespread agreement among scientists regarding the precise definition of aging, partly due to its highly complex nature. Simplifying this intricacy into a single figure, like an epigenetic age, can lead to misunderstandings.
Lastly, epigenetic clocks are influenced by an individual’s history of trauma, experiences of discrimination, and early life adversities. This renders their application at the individual level potentially problematic. On average, marginalized communities tend to exhibit indicators of accelerated aging when assessed by epigenetic clocks. Should insurance providers begin utilizing epigenetic age estimations to determine premiums, many individuals might face increased costs due to biological distinctions shaped by circumstances beyond their control, potentially exacerbating existing health inequalities.
Investigating the unfolding of aging over time
While epigenetic clocks are not deemed suitable instruments for making individual health decisions, this does not diminish their potential value.
Researchers have employed epigenetic clocks to identify lifestyle habits that, on average, can contribute to a slower aging process. Examples of such habits include reducing daily caloric intake, engaging in regular physical activity, adhering to a healthy diet, ensuring sufficient sleep, and refraining from smoking.
Related stories
- ‘Aging clocks’ indicate your biological age relative to your chronological age. How do they function?
- A new ‘biological aging’ test predicts your likelihood of mortality within the next 12 months
- Accelerated ‘biological aging’ is associated with diminished memory capacity
Epigenetic clocks can also be instrumental in evaluating novel drug therapies designed to mitigate specific aging processes. For instance, scientists have demonstrated that rapamycin, a medication linked to various aging mechanisms, can reduce the epigenetic age of human skin cells. Furthermore, some evidence suggests that a treatment aimed at regenerating the thymus may decelerate or even reverse epigenetic aging after a year of administration. However, these observed effects have been noted primarily when examining groups rather than individual subjects.
Epigenetic clocks are proving beneficial in advancing scientific understanding of aging processes, yet they are not to be mistaken for medical tests that gauge individual health. In the future, epigenetic measurements might serve a valuable purpose in guiding personal health choices. For the present, however, epigenetic clocks marketed as biological age tests are best utilized and refined by researchers who focus on population studies rather than individual assessments.
This adapted article is reproduced from The Conversation under a Creative Commons license. Access the original article here.
