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What is C Reactive Protein?


Updated April 23, 2014

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What is C Reactive Protein?

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Question: What is C Reactive Protein?

What is c reactive protein (CRP) and how is it related to colon cancer?


C reactive protein, or CRP, is a protein that is found in the blood. CRP levels can vary from person to person and they can vary in an individual over time. Several things can affect blood CRP levels. Elevated CRP levels indicate that there is inflammation in the body, which can put a person at greater risk for colon cancer.

What Would C Reactive Protein Measurements Tell Me?

CRP is a substance that changes in response to inflammation. The more inflammation a person has ongoing in his or her body, the higher the level of CRP. In this way, a person's blood level of c reactive protein is a non-specific measure of his or level of inflammation.

CRP is considered non-specific, because many things can cause CRP levels to go up. This is because many things can cause inflammation. An infection, such as a cold or flu, can cause CRP levels to rise, for example. Cigarette smoking, obesity, and uncontrolled diabetes can increase inflammation, and CRP levels, too.

How Is CRP Related to Colon Cancer?

Because CRP is non-specific, it cannot tell us whether a person has colon cancer. However, new research suggests that having a high level of CRP may increase colon cancer risk.

This does not mean that CRP causes colon cancer. Rather, inflammation increases colon cancer risk and CRP is an indication of high amounts of inflammation in the body. Here's how it works.

What Is the Connection Between CRP-Raising Inflammation and Colon Cancer?

Many people are familiar with acute inflammation, which is signaled by things such as a fever or swelling and pain. When we measure CRP we are looking for another form of inflammation: the chronic, low-grade inflammation that can go on in the body every day.

To understand chronic inflammation, consider that every cell in your body conducts ongoing conversations with the cells around it. When inflammation is in balance, these conversations are similar to a pleasant, neighborly chat. This would be apparent with a low CRP level.

When inflammation is out of control, cellular communication becomes nasty. It's more like a shouting match, and even may lead to pushing and shoving. Inflammation ratchets up the tone and volume of cellular conversations to damaging levels. When this is happening in the body, CRP levels will go up.

And the damage caused by excessive inflammation has been linked to development of many chronic diseases, including colon cancer. This means that anything that can help bring inflammation under control, may be an effective way to help lower colon cancer risk.

Learn how to reduce a high C reactive protein and you can take steps to improve your health. There are no guarantees that lowering CRP will lower colon cancer risk. But based on the latest research, the chances are quite good that the same steps that lower CRP will, indeed, lower colon cancer risk too!


Aleksandrova K, Jenab M, Boeing H, Jansen E, Bueno-de-Mesquita HB, Rinaldi S, et al. "Circulating C-Reactive Protein Concentrations and Risks of Colon and Rectal Cancer: A Nested Case-Control Study Within the European Prospective Investigation into Cancer and Nutrition." American Journal of Epidemiology 2010 172:407-418.

American Heart Association. Inflammation, Heart Disease and Stroke: The Role of C-Reactive Protein. Accessed: September 3, 2010. http://www.americanheart.org/presenter.jhtml?identifier=4648

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