Biological Age Testing: How Old Are You Really?

Biological age testing uncovers the real age of the body you live in. Many people fear the results, but the test is a useful tool for improving your body's age through lifestyle changes. Biological age testing companies pinpoint how old your body is and offer personalized, healthy changes to make you younger – even as your chronological age gets older.

Biological age vs. chronological age

Chronological age is the number of candles on your birthday cake — the age counted from the day you were born. By instinct, most of us understand that it's not the best measurement of how a body actually ages. We all age uniquely, according to a mix of our genetics, lifestyles, environment, and mental and relational health.

A better measure of age is one's biological age, also called physiological age or GrimAge — an unsettling reference to the Grim Reaper. Biological age refers to how old your body is and how your cells operate.

According to a study published in 2019 in The Journals of Gerontology, "Biologic age is a measure of individuals' predicted age based on biomarkers. Biological age can be estimated using clinical biomarkers readily available in physicians' offices."

The authors state, "Biologic age has been proposed as a measure of physical resilience, with opportunities to further our understanding of how genetics, health behaviors, the environment, and psychosocial factors influence individuals' ability to recover from stressors."

What affects biological age?

Aging is inevitable, but we can speed up or slow down the aging process with our lifestyle, relationships, mental health, and living conditions.

For example, people who smoke and people with Major Depressive Disorder tend to be two years biologically older than others.

Genetics is an aging factor that we cannot change. However, we can change what science calls epigenetics. According to the Centers for Disease Control and Prevention (CDC), "Epigenetics is the study of how your behaviors and environment can cause changes that affect the way your genes work. Unlike genetic changes, epigenetic changes are reversible and do not change your DNA sequence, but they can change how your body reads a DNA sequence."

Genetics refers to one's unchangeable DNA. Epigenetics, however, refers to the lifestyle and environmental factors that turn genes on and off, affecting how your DNA is expressed, also known as gene expression. While you may have a genetic propensity toward cardiovascular disease, type 2 diabetes, or mental illness, you can quiet those genes with lifestyle choices.

Because epigenetic factors powerfully impact aging, scientists have developed very accurate ways to test your biological age by measuring how epigenetics affect your body and age. They do this primarily by testing the biomarkers and DNA in blood or other tissue.

These epigenetic factors that make one age faster or slower aren't surprising:

How do biological age tests work?

Biological age testing is a tool that measures which body systems and organs are aging too fast. This empowers you to precisely target the organs needing the most care and lifestyle improvements to increase your longevity significantly.

Currently, the most comprehensive and accurate biological age tests, also called epigenetic age tests, use blood samples to measure these molecular biomarkers. Some tests collect skin or saliva samples instead of blood.

Testing companies typically use machine learning and artificial intelligence to improve test accuracy. To thoroughly test all your body's systems, biological age tests use the molecules in your blood — like DNA, lipids, and metabolites — as indicators of health throughout your body. This may include organ, immune, hormone, and metabolic health, to name a few.

A trustworthy test offers a thorough and multi-faceted internal review of one's cellular age. The assessment helps you focus lifestyle changes on the particular systems or organs — like your heart or liver — that are aging faster than other systems. As always, it's best to make changes with the help of a trusted practitioner.

Experts recommend tracking your age test every six months to see which lifestyle upgrades improve your age. Most improvement plans include diet, exercise, lifestyle, and supplement recommendations.

Common types of biological age tests

Currently, there are several ways to test your epigenetic clock.

DNA methylation

Tests that analyze your DNA methylation are considered today's gold standard for accurate epigenetic age testing. DNA methylation tests analyze molecules in your blood (epigenetics) to see how your DNA (genetics) expresses itself.

DNA methylation is the chemical modification of gene expression. It is tightly connected to a child's development and an adult's aging process. It is the body's way of turning on and off genes and is highly affected by lifestyle and environmental factors. Dr. Steven Horvath, the scientist who discovered the epigenetic clock, compares DNA methylation to rust, an epigenetic sign of aging.

Because DNA expression changes over time, it can be measured and analyzed throughout your life. To do so, scientists measure the beginning of the DNA strand, where methylation occurs, to examine whether specific genes are activated or silenced. Some researchers call this a DNA-methylation-based clock.

Telomere length

Some companies include telomere length as a way to measure biological age. Located at the end of chromosomes, telomeres help protect cell replication and DNA during cell division. Although telomere length can be a helpful addition to biological age tests, most experts believe DNA methylation to be a superior measurement.

NAD

Nicotinamide adenine dinucleotide (NAD) is a beneficial coenzyme that researchers say declines as we age. This decline differs between men and women and may be associated with conditions like cancer and cognitive decline. Lab technicians measure levels using a simple blood draw.

Gut microbiome and blood transcriptome

One's gut microbiome changes with age. These changes can predict biological age, particularly the depletion of a core bacteria group called Bacteroides. High levels of this bacteria may indicate older biological age.

Whole blood transcriptome refers to all of your cells' gene expressions found in your blood. These biomarkers associated with biological age may also help scientists develop future tests and interventions to help delay aging.

IgG Glycome

A 2022 study published in Frontiers in Cell and Developmental Biology reports that the Immunoglobulin G (IgG) glycome test is "one of the most potent biomarkers of biological aging." This test measures complex sugars called N-glycans attached to the IgG antibody, an important antibody commonly found in blood.

The composition of the IgG glycome changes predictably with age, health, and lifestyle choices, likely due to inflammation. As a result, this test is another helpful measurement of epigenetic age.

Choosing the best biological age test

At the moment, few healthcare providers collect these tests for you. You'll likely need to search online for a biological age testing company and closely follow their directions.

When looking for a trustworthy company, consider these factors:

• Type of sample collected. Experts currently recommend tests using blood samples because blood is the most widely researched age predictor. Various companies also used saliva, stool, and cheek swabs. If you can, aim to find a company with strong, published research backing their test type.
• Cost. Tests typically range from $95 to $499. Consider choosing an affordable test for your budget if you intend to test every six months to monitor improvements.
• Type of test. By thoroughly reading a company's website and the research supporting their test, you can personally decide which type is trustworthy and best for you.
• Depth of test. The most accurate tests will look at the most cells and DNA. Some DNA methylation testing companies report looking at nearly 1 million (out of 26 million) locations in your genome, while others look at 100,000. The more locations they test, the better they can analyze your methylation, giving you a more accurate assessment.
• Simple, clear process. Companies should have clear and easy-to-follow steps for collecting and mailing samples.
• Follow-up resources. The best companies offer ample resources, follow-up steps, and tools to lower your biological age. You can follow these steps carefully and cautiously on your own or take the results and recommendations to a healthcare provider for advice and direction.

For those located outside the United States, there are testing companies in Europe and Asia, like GlycanAge, Cerascreen, Longevity Box, and AgingAI, to name a few. However, many U.S. companies accept customers from around the world.

Hacking your biological age

Age is the number one risk factor for all chronic diseases and death. The only way to reduce biological age is to slow the aging process. Aging cannot be stopped altogether, but how one ages can be transformed by addressing lifestyle factors like diet, exercise, stress, toxins, and relationships.

Because aging is intertwined with disease, medicine will change radically as our understanding of epigenetic aging expands.

In the meantime, however, there's no reason to wait for biological age to be fully understood. Changing your lifestyle to transform your body, mind, and relationships is the clearcut and direct way to hack your biological age, helping you get younger as your chronological age gets older.