blood tests

2 minute read

Biomarkers: everything you need to know

By Nick Harland | Medically reviewed by Dr Nimlan Shanmugathas
finger prick blood test

Most of us have probably had their blood pressure taken before. You know the drill: you strap the monitor around your arm, wait 30 seconds or so, and then some numbers pop up on the screen. Those numbers are actually the millimetres of mercury (mmHg) in our blood, and they’re what we use to measure blood pressure. They’re also an example of a biomarker.

Let’s look at them in a little more detail.

What are biomarkers?

Biomarkers are used to measure various aspects of our health. 

For example, if you take a cholesterol blood test then your results will include a range of different biomarkers related to cholesterol levels. If these numbers fall outside of the expected range, it could be an early indicator of heart disease. The biomarkers related to a sexual performance blood test can reveal potential causes of erectile dysfunction and low libido.

Ultimately, biomarkers let us know if things in our body are working as they should be. They can help to reveal underlying health issues, and even predict potential health problems in the future. By regularly tracking your biomarkers and knowing the numbers, you can be more proactive with your health.

What do they measure?

Millimetres of mercury (mmHg) - the unit we use to measure blood pressure - is one of the best-known examples of a biomarker. But biomarkers are also used to measure plenty of other health characteristics.

Let’s take the example of urea. Urea is a waste product of urine that’s excreted from your body through your kidneys. If your urea levels are higher than normal, it may suggest your kidneys aren’t breaking your urine down as they should.

There are hundreds of other biomarkers that are used to measure different health characteristics. Some examples include:

  • Creatinine levels

  • Triglycerides

  • LDL (Low-Density Lipoprotein)

  • Free T4 (Free Thyroxine)

We sometimes combine different biomarkers to assess the effectiveness of different bodily functions. For instance, your eGFR (Estimated Glomerular Filtration Rate) is a combination of biomarkers that measures how well your kidneys are working. It’s based on a number of factors including your creatinine levels, age, sex, and body type.

Ways of measuring biomarkers

Blood tests can measure a range of biomarkers. But there are other ways of getting your body’s biomarkers too. For example, through a blood pressure monitor, urine test, or saliva sample.

What can biomarkers be used for?

They can help predict potential health issues. For example, elevated urea levels may not be causing you any harm as it stands, but could be an early indicator of other health problems later down the line. Keeping on top of your biomarkers means you can spot early signs and act accordingly.

Biomarkers are vital for drug development too. Around 90% of drug trials fail at the clinical trial stage. They often fail at that stage because that’s when the effect the drug has on biomarkers is measured - if it negatively affects too many biomarkers, it’s not approved.

They also make things a little simpler for both doctor and patient. They tell us more about our body and help to demystify a lot of our health-related concerns. Maybe more than anything, biomarkers help you to be more proactive with your health. Instead of waiting for issues to arise and physical symptoms to manifest, keeping track of your biomarkers can give an early indication if something (like cholesterol) is heading in the wrong direction. Knowing what your biomarkers are means you’re informed and equipped and can make any necessary lifestyle changes, however small. 

The numan take

Biomarkers are indicators we use to measure different aspects of our health, such as blood pressure or cholesterol levels. It’s good to keep regular track of them via blood tests, as they can reveal underlying health issues, predict future problems, and generally help you to be more proactive with your health.