Your biological clock
The ageing clock: a new way to determine your biological age
Can you measure how old you are?
We are all getting older. But one person ages faster than another. With new techniques, we can look at your so-called biological age. That is different from your chronological age. You do not need to measure that, because it is simply fixed.
What can you measure?
There are many ways to look at how biologically old someone is.
When you are young, height says something about growth and development, for example. But as soon as you are fully grown, that no longer works. In fact, at a later age, many people actually become slightly shorter again. Your performance also changes with age. For instance, you can walk less quickly or sustain an effort for a shorter time. By training, you can improve your fitness. Yet everyone understands that a fitness test only tells part of the story. You may be able to see whether someone is fitter or less fit than you would expect based on their chronological age, but that still doesn't really tell you how biologically old someone is.And when we look at chemical values?
Blood and urine tests
Now things are getting more exciting, because we all know that we can discover a lot about our bodies through blood and urine tests.
For example, we can determine whether someone has anaemia (too few red blood cells) or blood sugar levels that are too high, which may indicate diabetes.
Also, cholesterol, inflammation, vitamin deficiencies and problems with the kidneys or liver can often be detected via blood tests.
Biomarkers
We call these types of measurements biomarkers. These are measurable substances in the body that say something about health, disease or ageing.
Blood test
As we get older, many blood values gradually change with us. Inflammatory markers often become slightly higher, and cholesterol and blood sugar can also rise. Some vitamins are absorbed less well by the body. The function of the kidneys and liver can also gradually decline.
Therefore, blood tests often provide important information about health and ageing.
Even so, we cannot link these values directly to a single clear measure of biological age.
Urine test
As we get older, we more often see changes in urine tests related to kidney function and fluid balance. Sugar in the urine also occurs more frequently, for example in diabetes.
Sometimes more protein is also found. That can indicate wear and tear or extra strain on the kidneys. In addition, bladder and urinary tract infections occur more frequently at an older age.
However, we cannot directly link these measurements to a single clear measure of biological age either.
cervical mucus test
In a cheek swab test, a cotton bud is used to take a few cells from the inside of the cheek. Those cells contain DNA that can be examined.
Modern tests often look at small chemical changes on the DNA. We call those changes DNA methylation. They change slowly as we age.
Based on those patterns, researchers are trying to make an estimate of biological age. Some epigenetic clocks therefore specifically use cheek swabs as a simple and painless test material.
A cheek swab test can therefore reveal something about processes associated with ageing. Even so, it remains complicated. Different clocks use different measurement methods and the results can also be influenced by lifestyle, stress, sleep, smoking and illness.
Therefore, a cheek swab test does not provide a perfect or absolute measure of biological age either, but rather an approximation of how fast the body is biologically changing.
Conclusions
The tests in question are primarily chemical tests. While fitness tests mainly measure physical performance — such as the time someone can sustain a certain level of exertion — we are now entering the world of chemistry.
The characteristic feature is always: on the basis of chemical analyses, we can determine whether “something is there” (for example, signs of diabetes) or whether this is precisely not the case. We do not use it to determine biological age, and certainly not something like “the rate of ageing”.
However, the buccal swab test has shown us that there is a new anchor point and that anchor point is linked to changes in the epigenome.
What are we going to cover in this section?
Perhaps this part is the most interesting in the series because virtually everything revolves around measurements of the epigenome as the grand conductor of the genes.
Overview of the different chapters:
1. This home page: provides an introduction to the topic
2. An unexpected discovery: Steve Horvath discovers the biological clock
3. Why these clocks are so important
4. Who are the suppliers of these clocks?
Duration and prior knowledge
Duration and prior knowledge
It is desirable to have reviewed at least the sections “DNA of life, the code” and “DNA, the epigenome and your healthspan”.
How long does this part take?
You'll go through this section in about an hour. Would you like to delve deeper? Once you're familiar with the topics, you'll find plenty of videos and blogs on our site. If you dive into those, you'll naturally be longer — but it is extremely interesting!
Questions or assignments
You will sometimes come across questions or tasks. Don't let that put you off! You are under no obligation whatsoever, after all.
They are purely intended as extra depth for anyone who fancies it. So please feel free to just skip them.
