Does inflammation always show up in a blood test?
Inflammation can sometimes be detected in a blood test, but not in every case. Tests such as CRP or ESR can show when the body is responding to injury or illness, yet mild or local inflammation may not appear in the results.
Inflammation is part of the body’s normal healing process, helping to fight infection and repair tissue. When it continues for too long, however, it can contribute to ongoing symptoms or long-term health problems.
This article explains how inflammation is measured through blood tests and why the results may not always tell the whole story.
What is inflammation and why does it happen?
Inflammation is your body’s way of protecting itself when something goes wrong. It’s what happens when your immune system detects a problem, such as an infection, injury or irritant, and sends out signals to deal with it.
If you’ve ever noticed redness and swelling around a cut, that’s acute inflammation - a short-term response that helps healing. But inflammation can also happen inside the body without obvious signs on the surface.
Long-term or chronic inflammation can develop when the immune response doesn’t switch off properly. Over time, this can affect tissues and organs, contributing to conditions such as arthritis, heart disease or certain autoimmune disorders.
How is inflammation measured in a blood test?
Blood tests can detect certain markers that reflect inflammation in the body. These markers rise when there’s an inflammatory response, even if you don’t feel unwell.
The main ones measured in routine testing include:
High-sensitivity C-reactive protein (hs-CRP)
A high-sensitivity C-reactive protein (hs-CRP) test measures lower levels of C-reactive protein (CRP) in your blood. This protein is made by the liver in response to inflammation. The high sensitivity version of the test can detect even low levels of inflammation, making it useful for spotting subtle changes linked to chronic health risks.
Ferritin
Ferritin is best known as an iron-storage protein, but it can also rise when inflammation is present. High ferritin levels might indicate that your body is reacting to an infection or other underlying issue.
At Bluecrest Wellness, our Inflammatory Profile measures hsCRP and ferritin, providing a detailed picture of inflammation throughout the body. The test also includes a grip strength assessment, which offers a functional measure that can relate to general health and longer-term inflammation.
These checks together help identify whether inflammation might be present, even when symptoms are mild or vague.
Can inflammation exist without showing up in a blood test?
It’s possible to have inflammation that doesn’t appear in your blood results. This might happen when:
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The inflammation is localised, such as in a joint, tendon or small area of tissue
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The inflammation is at a very early stage and hasn’t triggered a strong response
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Individual immune responses vary, so not everyone produces the same level of inflammatory proteins
For example, someone with mild tendon inflammation might notice pain and stiffness without any change in blood test results. Likewise, inflammation in the gut or skin can sometimes remain below the threshold of detection, even when symptoms are noticeable.
Blood tests provide a snapshot in time, so results can also vary depending on when the test is taken. If inflammation comes and goes, timing can affect whether it’s picked up.
What do raised inflammation markers mean?
Raised levels of hs-CRP or ferritin indicate that inflammation is happening somewhere in the body, but they don’t reveal exactly where or why.
The cause could be something short term, such as a recent cold or injury, or part of an ongoing condition that needs monitoring. Due to these markers being non-specific, results are always interpreted alongside symptoms, medical history and other findings.
If your results show raised inflammation markers, your healthcare provider may suggest repeating the test, running further checks or exploring possible causes. Sometimes, inflammation naturally settles once the underlying issue improves.
What symptoms might suggest inflammation?
Some signs of inflammation are easy to spot, while others can be more subtle. You might notice:
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Ongoing tiredness or fatigue
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Muscle or joint aches
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Swelling or stiffness
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Digestive discomfort
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Low mood or “brain fog”
These can overlap with many other issues, which is why testing can be so useful. A blood test can confirm whether inflammation might be contributing and help guide your next steps.
How can lifestyle affect inflammation?
Everyday habits play a big role in how your body manages inflammation. A diet rich in fruit, vegetables, whole grains and healthy fats can help reduce inflammatory responses, while regular movement supports circulation and immune balance.
On the other hand, smoking, excess alcohol, chronic stress and poor sleep can all make inflammation worse or more persistent.
Testing can help you understand where you stand. If your Inflammatory Profile shows raised markers, small adjustments such as improving diet quality, increasing activity or managing stress could help lower levels over time.
When should you consider an inflammatory blood test?
An inflammatory blood test can be useful if you:
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Experience unexplained aches, pains or fatigue
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Have ongoing symptoms without a clear cause
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Are managing a long-term condition and want to track progress
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Want reassurance that there’s no hidden inflammation affecting your health
It’s a simple way to gain more insight into your body’s inflammatory activity and can help identify whether further checks are needed.
Understanding your results
If your test results are normal, that’s reassuring and suggests there’s no significant inflammation at the time of testing. However, if symptoms persist, it’s worth discussing them with your GP, as inflammation can fluctuate.
If your results are raised, your healthcare provider will look at your overall picture, including lifestyle factors and medical history, before recommending next steps. This might include additional tests, treatment or follow-up monitoring.
Remember that inflammation isn’t always harmful. It’s often a sign that your body is responding to something, and the key is identifying whether that response is short-term or part of a longer pattern that needs attention.
Take a proactive approach with inflammation testing
Blood tests are one of the most effective ways to understand your body’s inflammatory activity. They can help identify potential problems early, track changes and guide healthy lifestyle decisions.
If you’d like to check your inflammation levels, Bluecrest Wellness offers an Inflammatory Profile that measures high sensitivity CRP and ferritin, along with a grip strength assessment. Together, these provide a detailed picture of inflammation and overall health.
You’ll receive clear, easy-to-understand results and guidance on what they mean, helping you take proactive steps to support your wellbeing.
Need help? Call free on 0800 652 2183 to speak to one of our team.
Anna Jones
Chief Nursing Officer, Bluecrest
Graham Jones
Medical Writer
