How To Assess If You Are Ageing Well: Understanding Biological vs Chronological Age

Life and death are the two hard truths. But we humans have long desired to live longer. In 1900 the average life expectancy was 32 years, but by 2021 it more than doubled to 71 years. Advancements in healthcare facilities, hygiene and nutrition are among the reasons for the increase in life expectancy which is expected to increase to 78.1 years by 2050. But how are we ageing?

Ageing is an inevitable part of life, but the rate at which we age can vary significantly from person to person. While chronological age is simply the number of years we've been alive, biological age is a more complex measure that reflects the health and vitality of our cells and tissues. New studies have shown a gap between chronological and biological age, which can increase the risk of disease and mortality. While we can easily calculate our age based on when we were born, the biological age can be measured by using blood samples, Now a company offers a simple cheek swab to determine our biological age. The company Tally Health offers a less invasive alternative called CheekAge using a cheek swab,

In a study published in the scientific journal Frontiers in Aging, Tally Health's team explains how they used blood samples from a dataset of 1,500 senior citizens in the UK to evaluate the accuracy of their CheekAge technology. The results demonstrated that the difference between biological and chronological ages is closely linked to mortality risk. "This model, which utilises more than 200,000 DNA methylation sites to produce an epigenetic age (biological age) estimate in an easy-to-collect tissue, was trained to correlate with a variety of lifestyle and health factors, including weekly exercise, sleep quality, diet, stress, smoking status, alcohol intake, and body mass index. For example, health-promoting behaviours like more frequent weekly exercise were associated with a lower delta age (epigenetic age - chronological age) while less health-promoting behaviours like heavy alcohol intake correlated with a higher delta age," from the research paper published in Frontiers in Aging.

How Biological Age Tests Work

To determine the biological age a process called DNA methylation is most used. As we grow older, chemical markers known as methyl groups attach themselves to our DNA. These tags serve as indicators that researchers can use to estimate a person's biological age. DNA methylation doesn't change the DNA sequence itself, but it can influence how certain genes behave. Over time, factors like diet, hormone levels, stress, medication, and pollution can impact the levels of DNA methylation in your body. In other words, the choices we make and the environment we live in directly affect how our cells age.

Why should I care about Biological Age?

Well, we cannot change our chronological age, but we can change our biological age. By making certain lifestyle changes we can remove the factors which are adding to the stress. Exercising, eating healthy and changing to a less polluted living environment can slow the biological ageing process.