Biological Age & what it REALLY means | 9 - Longevity Science #3
Biological age—that is, how old your cells and tissues are based on physiological function—is a multifaceted and intricate concept that transcends numerical representation. Unlike chronological age, which refers simply to the number of years you have been alive, the concept of biological age delves into the dynamic interplay between physiological processes, genetic predispositions, and environmental influences that collectively shape an individual's health trajectory. Geroscientists are currently studying the biological mechanisms that might impact your biological aging rate and perhaps reverse some of the functional declines that accompany aging.
Check out the links below for further information and/or reading about some of the things we discussed in this podcast episode. Note that we do not necessarily endorse or agree with the content of these readings, but present them as supplementary material that may deepen your understanding of the topic after you listen to our podcast. This list is in no way exhaustive, but it’s a good start!
This study was one of the first to build a model to estimate biological age from DNA methylation patterns. One could imagine DNA as a set of instructions, like a recipe book, that tells our bodies how to work; and DNA methylation as little tags or markers that attach to these instructions. These tags can change as we age, a bit like how notes or highlights might change in a book as you read it again and again—and in changing, affect how genes get turned on and off.
Decreased epigenetic age of PBMCs from Italian semi-supercentenarians and their offspring
When people talk about “epigenetic clocks” or “epigenetic age”, they are typically referring to methods that use DNA methylation changes as a means for estimating biological age. Underpinning these methods is the idea that certain patterns of DNA methylation change with age. According to this study, the offspring of semi-supercentenarians—people who live up to 105-109 years—have a lower epigenetic age than control subjects. Centenarians are also nearly nine years “younger” biologically than their chronological age.
This study compares the ability of five algorithms to predict biological age. The “winning algorithm”, the 2006 Klemera and Doubal method (KDM), predicted mortality better than chronological age as well as any of the other algorithms tested.
A new approach to the concept and computation of biological age
The researchers Petr Klemera and Stanislav Doubal developed the Klemera and Doubal method (KDM), an algorithm for calculating biological age that outperformed other algorithms (see previous article). They detail tools researchers typically use to compute biological age—multiple linear regression, factor analysis, principal components analysis—and describe the mathematics behind their own method.
How to measure biological age | Prof Brian Kennedy
National University of Singapore Distinguished Professor of Biochemistry and Physiology Brian Kennedy chats about biological age with Eleanor Sheekey of The Sheekey Science Show. He describes how, unlike chronological age, markers of biological age might oscillate in response to different circumstances—sleep, a virus, exercise levels—and vary from one week to the next. As such, single timepoints may not be informative. He also discusses ongoing research to collect multiple potential biomarkers of aging, merge them, and see if they correspond or interact.
