38-year-old Anders took three “biological age tests”. So how old is his body?

I was born in January 1986 and am therefore 38 years old at the time of writing.

But in science, people have started to talk about two different types of age:

• Chronological age (time since date of birth).
• Biological age (body’s state of health).

My chronological age does not say much about how healthy I am and how long I will live.

So how old is my body? And how quickly does it age?

These are the questions I have asked myself while having my biological age measured in three different places.

In line with the interest in healthy ageing, a number of methods have appeared that try to satisfy the need to know how the body is doing, but there is much that is uncertain about these tests.

This is a test of tests. I have received three answers about my biological age and then I have had an expert assess the results, the methods – and how this type of test can affect both society and our health in the long term.

– Measuring biological age will certainly become more widespread in an attempt to prevent disease and target treatment to the individual patient. The big question is how we will handle the results, says Lene Juel Rasmussen.

Rasmussen is a molecular biologist and researches what she calls “biological clocks” as a professor at the Center for Healthy Aging at the University of Copenhagen. In other words, she works scientifically with the field.

Here are the answers we came up with together.

How I became 10 years younger with the Tanita test

My little experiment got off to an exciting start.

In April 2024, I visited one of Copenhagen Medical’s private clinics to take a Tanita weight test.

I took off my clothes and, wearing only my underpants, stepped on what looked like a traditional scale that measures the body in kilos. But the Tanita scale can do more than that, and the MC-780 model I encountered had both a plate for the feet and two metal handles for me to grasp.

That’s exactly what I did. Next, weak electrical signals were sent through my body to measure the distribution of fluid, fat tissue and muscle mass.

And the result? I had it printed on an A4 sheet with blue and yellow colors:

29.

The number was the first thing I noticed. It was next to the box marked ‘Metabolic age’.

– Just ignore that box, said the employee from Copenhagen Medical who carried out the study.

But it was difficult. When he circled metabolic age with a pen, I felt 10 years younger. I straightened my back.

– Everyone will focus on that number, said the employee and pointed. – But really, it’s all the other things we want to focus on with this test.

The Tanita test also listed fat percentage, muscle mass, fluid balance and metabolism. And these numbers are more important, he explained.

– I had a fat percentage of 17.9 per cent, which was on the verge of being too high. The muscle mass was a little too low.

Metabolism, fluid balance and combustion were indeed “standard” or “normal”. But I understood the conclusion to mean that I was far from being a specimen.

The expert’s assessment of the Tanita test:

On some parameters, I may have a body that corresponds to the body of an average 29-year-old. But that does not mean that I will live 10 years longer than can be expected from a man of my age, according to Lene Juel Rasmussen.

– The Tanita test says something about body composition in relation to average values ​​in the population. But it does not tell you whether you have a disease – and that is of great importance, she says.

– So if you are told that your body is 10 years younger than your chronological age, don’t be fooled. It doesn’t matter if you’re healthy or when you’re going to die. It says something in general about your physical form.

The questionnaire confirms low age

– Based on our test, your biological age right now is 29 years old, and you will be about 93 years old.

That was the answer in the next test I took: a questionnaire under the heading “Finn your biological age” on the website Alun.dk.

In the test, I answered a series of questions about marital status and lifestyle, including work, relationships – and how much vegetables I eat.

– Regardless of the result, you can still improve your health, said the text about my biological age.

29 years. I started to believe it.

The expert’s assessment of the questionnaire

One should be careful with the results from questionnaires, says Lene Juel Rasmussen.

– You fill in the answers yourself, and no one checks it. Therefore, I think it is very difficult to find scientific support for this type of questionnaire survey to say something accurate about your state of health.

Rasmussen says that she took the test herself and was even slightly encouraged by the answer.

– It is a very unscientific test. But therefore it can be a fun way to check yourself, and maybe it can even motivate you to improve your health, she says.

SuPAR: Blood test was a bit disappointing

Finally, I visited the private clinic Aetas, a so-called longevity clinic who works with “health optimization”.

They took a blood test they called suPAR.

The SuPAR test was invented by the Danish molecular biologist and aging researcher Jesper Eugen-Olsen, and in more than 1,000 studies it has been used as an indicator of aging and the risk of age-related diseases.

The test measures chronic inflammation in the body by determining the level of a protein called suPAR (soluble urokinase plasminogen activator receptor).

And the result was both discouraging and encouraging:

“You can consider yourself a healthy person with a well-functioning immune system,” was the reply from Aetas.

“Your suPAR level is within the normal range, indicating that you are relatively healthy and have a low likelihood of developing certain diseases associated with elevated suPAR.”

My biological age in the suPAR test: 38 years. Exactly the same as my chronological age, and a little disappointing.

The expert’s assessment of the SuPAR test:

Lene Juel Rasmussen believes the SuPAR test is the most thorough of those I have had performed:

– There are studies that show that the level of inflammation increases somewhat with age, so it makes sense to measure chronic inflammation in the body as an indicator of aging and risk of disease, she says.

– In the suPAR test, the molecules in the blood are checked, and this gives a slightly more detailed picture of the state of health. But the various tests perhaps work best in combination, she adds and emphasizes a general reservation about biological age tests:

– We still have not found a biological clock that is sufficiently scientifically validated to be able to predict our biological age.

Should the insurance company know when you die?

But it is probably only a matter of time before there is a generally recognized test, believes the molecular biologist from the University of Copenhagen. A test that will probably also be used in the public health system.

– Biological clocks can be used as a preventive tool. They can help to predict the risk of disease and make it possible to target the treatment to the individual, says Lene Juel Rasmussen. – But biological clocks also raise a number of ethical dilemmas.

She emphasizes the discussion about who should have access to the detailed data about our health. Data that may be able to predict the risk of disease.

Should we ourselves have access through the public sector? Should artificial intelligence or foreign researchers have access? And what about the insurance companies, are they supposed to know when we might die?

– We have to think about how to answer these ethical questions at the same time as we continue the scientific work of measuring biological age, says Rasmussen.

© Videnskab.dk. Translated by Lars Nygaard for forskning.no. Read the original story on videnskab.dk here.