Quick overview of what you’ll learn from this blog post:
- What are biomarkers of aging?
- How do we use those biomarkers?
- What makes a good biomarker of aging?
People have long been fascinated by the fact that some people seem to age rapidly in terms of health and appearance, while others age more slowly. How old you are doesn’t necessarily correlate to how your body is aging at a cellular level. After all, there are 70-year-olds who run marathons, and 25-year-olds with greying hair and chronic mitochondrial dysfunctions that make it hard to get out of bed. Being 30 years old isn’t a guarantee that your stem cells are vigorously healthy – chronological age and biological age (the Hallmarks of Aging) are only loosely tied together. Chronological age is tracked by your birthday – it’s simply how many years you’ve lived on this earth. Biological age looks at how the systems in your body are holding up after all this time.
As time passes, there are more chances for errors to occur in things like epigenetic management of genes, or protein misfolds. After all, your body folds trillions of proteins throughout your life. You get millions of new cells, each with an incredibly complex system that needs to be perfectly replicated each time. There’s a lot of chances to make a mistake, each year you’re alive. The more years you’ve been alive, the more it’s likely that your cells have goofed a couple hundred times, and that’s starting to build up.
However, there are also changes that are made to aging that happen in response to what you’ve lived through. Things like extreme stress, excessive alcohol consumption or smoking, chronic dehydration, and radiation can actually change how our genes are expressed. These changes are called epigenetic alterations, which have a cascading effect on many other hallmarks of aging. Epigenetic alterations can become outwardly visible, but they are often subtle changes throughout organs and tissues. They manifest in little tweaks to how well a cell can fight off the development of tumors, or how well it can regulate its own nutrient uptake.
Finding a reliable way to measure and track how your lifestyle affects aging has become the next great enterprise in integrative and preventive medicine.
A biomarker is a diagnostic tool that uses a change in the body to indicate something else, like general health or disease progression. Typically, a biomarker is found in blood or other tissue. A biomarker can indicate normal or abnormal processes. For example, your doctor may track blood pressure and cholesterol levels. These are two biomarkers which can indicate heart health.
To track biological aging, which happens in every cell across your body, you need some sort of marker that is present across the entire body, which can provide clinically useful information about the progression of the hallmarks of aging.
Since the 1980’s, it has been recognized that valid and reliable biomarkers of aging are needed to achieve the longstanding goal of understanding, slowing, and reversing the process of aging. After decades of research, a few notable biomarkers have been found, including telomere length, transcriptome profiles, protein and lipid metabolism, to name a few. All of these biomarkers have been used to determine biological age, yet none of them qualify as good biomarkers.
What is a good biomarker?
A good biomarker needs to be:
- Able to provide clinically relevant information
- Objective – not swayed by a bias
- Quantifiable – translates to specific data, not vague ideas.
- Precise – When measuring the same item over and over, the measurements will be very similar.
- Accurate – Accuracy refers to how close a measurement is to the ‘true’ or accepted value.
A reliable biomarker, once extensively studied and replicated, leaves little room for error. If the biomarker you are using to assess a biological function leaves space for doubt, it is probably not a good diagnostic tool.
A good biomarker for aging would differentiate people who are of the same chronological age, yet have different rates of biological aging. They also would have been studied across a variety of demographics, over an extended period of time.
Quantitative biomarkers of aging should be able to define a group of measurements for ‘healthy aging’. It should be able to predict the outcomes of healthy or unhealthy aging. It should be able to narrow down a specific biological feature to explain the biological process behind aging and aging-related diseases.
And this is how researchers narrowed in on Epigenetic Biological Aging, and the aging clocks that use it.
The search for the best methods of testing biological age continue to improve. Several decades ago we could only rely on crude measurements, such as “the number of cigarette packs you smoked per day plus your chronological age”. Some tried to create biomarkers from analyzing purely outward expressions of age, like someone’s grip strength, their ability to maintain balance, or mental acuity to calculate biological age. Telomere length was a popular marker for some time. In recent years, epigenetic clocks seem to be the most widely accepted biomarker of aging, and several of these clocks are now offered to the public for use. This search will continue as our ability to detect, test, and validate biomarkers continues to improve.
If you’re curious about your biological age, or are interested in a biological age test, get started here.
This blog was written in partnership with TruDiagnostic. TruDiagnostic is a Health Data company, specializing in epigenetic testing & research. They use a multi-omic approach to help scientists, physicians, and patients understand and benefit from the information found in the fluid epigenome.
The primary focus for TruDiagnostic is DNA Methylation – they offer a variety of algorithms and lab services for researchers, physicians, and consumers who want the most accurate and insightful longevity analysis from a CLIA-certified and HIPAA-compliant lab.
TruDiagnostic began with TruAge – a test that measures Biological Age by looking at Methylation. They now provide a full suite of aging related metrics. This includes telomere length measurements, intrinsic and extrinsic age calculations, immune cell subset deconvolution, current pace of aging, and more. It is available through AgelessRx here.
TruAge is trusted by clinical trials and academic research institutions across the world.
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.