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Experts Discuss Biological Age Testing Methods, Benefits and Limitations of At-Home Kits
Biological age, which measures cellular wear and tear, differs from chronological age based on genetics, lifestyle and medical history. At-home test kits using epigenetic clocks estimate this age but have limitations in accuracy and application. The global market for these tests reached $1.28 billion in 2024 and is projected to grow to $3.09 billion by 2033.
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Chronological age counts the years since birth and advances uniformly for everyone. Biological age, also known as epigenetic age, reflects changes in the body at a cellular level influenced by factors such as genetics, lifestyle habits and medical history.
According to Dr. Douglas Vaughan, director of the Potocsnak Longevity Institute at Northwestern University’s Feinberg School of Medicine, biological age does not always progress at the same rate as chronological age. “Every time you have a birthday, you add another year to your life,” Vaughan said.
Biological age captures internal changes over time, as Vaughan explained. Scientists estimate it through methods including epigenetic clocks, which analyze DNA methylation patterns at the molecular level. These clocks, originally developed for clinical research, are now available in direct-to-consumer kits.
“We have lots of tools now that allow us to get some insight into a given individual’s biological age,” Vaughan said. The field of biological age measurement is expanding as new techniques emerge.
The market for biological age testing has grown with the longevity industry. According to market research firm Dataintelo, the global market reached $1.28 billion in 2024 and is projected to reach $3.09 billion by 2033. At-home kits are sold online, with prices ranging from $299 for saliva-based tests to $499 for blood-based tests.
These kits provide health insights, but experts note variations in quality and reliability. Vaughan stated, “The measurement of epigenetic age is not prime-time yet for general consumers,” adding that the data and value of such tests remain uncertain.
Epigenetic clocks use algorithms based on DNA methylation, a process that regulates gene expression like a dimmer switch, according to Daniel Belsky, an associate professor of epidemiology at the Robert N. Butler Columbia Aging Center at Columbia University.
