Updated by Dr Francesca Haarer BSc, PG Cert (Med Ed), BMBS, MRCS and Dr Kate Smith BSc, MBChB

Updated date May 2025

 

Curious about the idea of testing for biological age?

Research believes it could be key to understanding your body's actual age, beyond simply your years spent on Earth. 

So how do you calculate biological age? Current science shows there are a few promising approaches.

Here, we'll go through what biological age means, possible testing methods and accuracy. Plus, how you can do a biological age test yourself.

What is biological age?

The latest research suggests that biological age is a prediction of how fast your body is ageing.¹

As yet, we don’t have all the answers about the mechanisms behind biological age or how they affect each person. 

However, one thing is clear: biological age could be better at telling us how fast someone is ageing compared to their actual age.¹

What is the difference between biological age and actual age?

Your actual age – the number of years you’ve been alive – is just one way of understanding age.

Biological age is a new way to describe age, through honing in on different indicators in your body.²

This can involve looking at the health of your cells, checking how well your organs are working, or by considering health on a whole-body level.³⁻⁷

It's like looking at age through a whole new lens, giving you a deeper understanding of how your body is ageing over time.

Why is biological age important?

Biological age may help give us a deeper understanding of a person’s health and wellbeing. 

Here are 3 reasons why understanding biological age is important.

1. It may impact lifespan and quality of life

Calculating biological age has the potential to show if you're ageing faster or slower than your actual age.⁸

This information can help you to make more informed decisions about your health and wellbeing. Long term, these decisions may lead to improvements in your overall lifespan (how long you live) and your quality of life.¹,⁹

2. It may support a healthy lifestyle

Understanding your biological age can help highlight areas for improvement in your lifestyle.

By comparing your biological age to your actual age, H&B&Me focus on building healthy habits that may positively impact how long and how well you live.

3. It may help personalise preventative healthcare

Biological age could help improve preventative healthcare.

Soon, doctors may be able to use biological age to see who is more likely to get certain diseases.¹⁰

This information could allow them to provide personalised guidance to help people stay healthy, like specific lifestyle adjustments.

We already know that healthy lifestyle choices improve health and prevent diseases.¹¹ Sharing this knowledge based on people's biological age is an exciting tool for future healthcare.

How to test for biological age

Biological age testing is a fast-growing area of research. 

Multiple methods exist, from cell testing to whole-body assessments.³⁻⁷

Scientists believe combining lots of factors may give the best result, but we believe the most effective testing method is still unclear.

Below, we’ll explore some emerging ways to test for biological age.

1. Measuring cell changes

One way to test for biological age is by looking at your cellular health.¹²

This involves studying what's happening inside your body's cells, such as changes in DNA, cell communication and cell damage buildup.¹²

These tests can be very invasive and costly, as they require taking samples from organs like the liver.

2. Measuring tissue & organ system function 

This method focuses on looking at health markers like your blood glucose, cholesterol and inflammation levels to see how well your body's tissues and organs are functioning. (4)

3. Measuring whole-body changes

This way looks at your whole-body health, not just individual markers, to get a broader picture of biological age.

It considers things like strength, muscle and bone health, and thinking skills. Some tests might involve physical tests and MRI scans for bone and muscle density.

4. Using risk modelling

This method uses your health data and habits to estimate your future risk of health problems like heart disease and diabetes.

It also tries to estimate how long you might live on average (your lifespan). 

Factoring in your health history and lifestyle choices, the approach creates a single, easy-to-understand score that reflects your overall health. This score is then translated into your biological age.

Unlike some biological age calculators, this method is affordable and easy to use as it doesn’t require any specialised tests.

How does H&B&Me calculate biological age?

H&B&Me offers a free biological age calculator that uses a science-based questionnaire to assess your health habits. 

This information is then used to calculate your biological age based on risk modelling and lifestyle data.

Unlike some methods, it doesn't require specialised tests and provides an immediate score.

The best part? Your biological age isn't fixed. It updates to reflect changes in your health as your habits evolve.

Are biological age tests accurate?

Accuracy refers to how close a measurement is to the real value, and how consistent the results are when the test is repeated. (5) It helps us determine if information is reliable.

Accuracy in biological age would mean how well a calculated age reflects a person's true inner health.

However, as we've seen, there are many ways to measure biological age. This makes it difficult to assess the accuracy of biological age testing precisely.

Hopefully, with ongoing research, it won't be long before we can say how accurate biological age tests are.

Plus, this research may help us determine the ideal way to test for biological age.

What affects your biological age?

Many things affect biological age. For example, there’s lots of evidence that certain lifestyle behaviours support healthy ageing. These include good nutrition, regular exercise, better sleep and emotional wellbeing. (6)

Other factors could have a negative impact on your body’s ageing process. These include smoking, not making time for rest, and nutrition choices (for example, eating a lot of ultra-processed foods). (7), (8)

How to improve your biological age

There are things you can do to help yourself age well and potentially improve your biological age.

Studies show healthy lifestyle choices lead to ageing well, and may slow down the ageing process. (9), (10) 

Below, we’ll explore 4 science-backed actions that may help improve your biological age.

1. Eat nourishing food 

Eating a balanced diet rich in both fibre and protein may improve your biological age.

Aim for 30g of fibre daily – think fruit, veggies and whole grains.

Target your protein intake at around 0.75-1.2g per kg of your body weight. Healthy protein choices include lean meats, fish or plant-based options like beans and lentils.

2. Move regularly

Moving more throughout the day may also help improve your biological age. 

This is because being sedentary (sitting down) for long periods is associated with greater health risks. Regular activity has been shown to improve your health, reduce disease risk and promote long life. (11) 

Aim to workout too, ideally 3 times a week with lots of variety. Regular exercise with a mix of cardio, strength and flexibility supports heart health, helps you build muscle and bone strength, and keeps you flexible and mobile. (12)

3. Prioritise sleep

Our bodies need to spend enough time in deep sleep to help maintain emotional wellbeing, and for recovery of our muscles, tissues and immune system. 

Aim for 7-9 hours of quality sleep each night, adjust your environment for a good night’s rest and have a consistent routine to signal to your brain it's time to unwind and sleep.

4. Take care of your emotional wellbeing

Emotional wellbeing plays a crucial role in healthy ageing. So, it makes sense that nurturing it may positively influence your biological age. 

Strong social bonds, meditation and spending time in nature can all help to reduce stress, sharpen focus and improve sleep quality. These benefits, when combined, can help contribute to a stronger emotional state.

By prioritising these 4 areas, you can contribute to a healthier you and potentially improve your biological age.

The final say

Biological age testing is a new field that can help you understand how your body is ageing on the inside.

There are different ways to test for biological age, and the results might surprise you. Your biological age could be younger or older than your actual age. 

The good news is, simple lifestyle choices may make a big difference in helping you age healthily. You might even be able to slow down or even reverse your biological age!

Ready to find out more? Download the H&B&Me app to calculate your biological age and start your journey to a healthier you.

 

References

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