Biological Age: What's the Best Test?

Biological Age: What's the Best Test?

Understanding your "biological age" can be a powerful tool for improving healthspan—the years of life spent in good health. Unlike chronological age (based off your birthday), biological age reflects how quickly your body is aging based on molecular markers. This can reveal how fast (or slow) you're aging. But with multiple tests out there, how do you know which biological age test is the most accurate for you?

Lifespan = years of life, but healthspan = years of life spent in good health

Blood Biomarker Tests to Measure Biologic Age

The easiest way to estimate your biological age uses standard blood tests. Key blood tests can reveal your organ function and overall health, including:

• Cystatin C (marker of kidney function)
• Albumin (marker of nutrition and liver function)
• C-reactive protein (CRP; a measure of inflammation)
• White blood count (measure of immune activity)
• Hemoglobin A1C (measure of metabolic health)
• And several more

These key biomarkers form a composite score to determine your biologic age.

As we age, the function of our organs naturally declines. These composite scores give a practical snapshot of this decline, effectively estimating your biological age without directly analyzing DNA. While affordable and easily accessible, these tests provide a limited view. They focus primarily on organ function without capturing deeper molecular changes occurring within your cells.

These composite scores have also changed over time, and your doctor at Clarus Health will use the latest research in calculating your composite score.

Biological Age From DNA Methylation Clocks

A more sophisticated method for estimating biological age measures accumulated changes to your DNA. These changes are called "DNA methylation patterns" and are part of a field known as epigenetics. Epigenetics comes from the Greek "epi," meaning "on top of," reflecting how these molecular changes layer onto your existing genetic code.

Your DNA Methylation Clock is the most advanced measure of biologic age

Methylation specifically refers to adding methyl groups—tiny chemical tags—to your DNA at specific sites, changing how genes are expressed without altering the underlying genetic sequence.

DNA methylation patterns reliably change with age, exhibiting predictable hypomethylation (loss of methyl groups) and hypermethylation (gain of methyl groups) across the genome. These changes serve as accurate predictors of biological age.

The most advanced methods combine methylation data with clinical markers to enhance prediction accuracy. These clocks not only estimate biological age but also predict lifespan and healthspan outcomes. Indeed, research indicates that methylation patterns at age 50 can predict with surprising accuracy who will live past 100.

Lifestyle factors significantly impact methylation patterns. Smoking leaves a distinctive epigenetic fingerprint, clearly indicating accelerated aging in vital organs. Conversely, higher socioeconomic status, regular exercise, and diets rich in fruits and vegetables correlate with younger methylation-based biological ages. Additionally, methylation patterns can reflect immune system health, as specific immune cell activities appear in the epigenetic markers, revealing insights into immunosenescence—the age-related decline of immune function.

Interestingly, methylation patterns in brain cells also correlate with neurological conditions, including Alzheimer's disease. Epigenetic age acceleration is positively associated with Alzheimer's pathology, such as increased amyloid deposits and neurofibrillary tangles, making methylation clocks a potential early detection tool for cognitive decline.

Challenges and Limitations with Biologic Age Measurements

While DNA methylation tests represent cutting-edge science, important challenges remain in accurately measuring biologic age. The precision of these tests depends heavily on several factors:

• Tissue and Cell Specificity: DNA methylation patterns differ across tissues and cell types, meaning a single blood test might not accurately represent whole-body aging.
• Cellular Diversity: Organs are composed of cells of varying ages, creating genetic and epigenetic mosaics. Understanding how to integrate data from these diverse cell populations is an ongoing challenge that might require advanced single-cell analysis.
• Calibration and Validation: Each methylation clock needs rigorous calibration against real-world health outcomes. Without standardized validation methods, clock accuracy can vary significantly between labs and testing companies.

Personalized and Expert Interpretation is Key for Biologic Age Data

As exciting as these biological age tests are, they have many shortcomings. Misinterpretation can cause unnecessary anxiety or misguided health interventions. That’s why working closely with your doctor at Clarus Health is so important. At Clarus Health, our doctors are experts in longevity medicine and are updated with the latest longevity research. Our doctors focus on helping you best select, interpret, and act on biologic age data to optimize your lifestyle. Often, medications or supplements can potentially reverse your methylation age and improve your overall healthspan.

Contact Clarus Health today to start your journey towards living healthier and longer!