C reactive protein (CRP) is a protein whose concentration within the blood increases when inflammation or bacterial infection is present. Levels can also increase after a heart attack, surgery or trauma and it is often referred to as an acute phase reactant.
CRP is used to look for infection and can also be used to test individual risk for cardiovascular disease. CRP is an inflammatory biomarker and can be used to detect individuals who are at a greater risk of heart attack or stroke. Inflammation plays a key role in atherothrombosis, a condition which is a major cause of acute coronary syndromes and cardiovascular death. It causes the development of plaques in the blood vessels which can dislodge and go on to block the blood flow to the heart or brain causing a heart attack, stroke and/or death.
As CRP is an inflammatory biomarker, it can be increased in other types of illnesses. The CRP test can identify inflammation but can’t pinpoint exactly what is causing it. So, raised levels may be caused by bacterial infections, arthritis or intense exercise.
You may not have any specific symptoms if you have high CRP levels. However, you may be at greater risk of cardiovascular disease or stroke if:
There is little scientific evidence to show that diet can reduce CRP levels. However, following the Mediterranean Diet can help to reduce inflammatory state associated with metabolic syndromes and can also protect against the development of cardiovascular disease. Ensuring the immune system is well maintained through diet can also help to reduce the likelihood of inflammation.
The Mediterranean Diet has been shown to reduce inflammatory markers in individuals with metabolic syndrome. The diet is characterised by a high intake of fruit, vegetables, nuts, olive oil and grains as well as a moderate consumption of fish and wine. The Mediterranean Diet promotes a low intake of processed and red meat as well as whole-fat dairy products such as milk and cheese.
Dietary polyphenols have antioxidant properties which have a protective mechanism against oxidative stress. This, in turn, means that intake can help to reduce the risk of chronic and degenerative disease. Good sources of dietary polyphenols are fruits, vegetables, grains, herbs and spices such as ginger and turmeric.
CRP has been shown to increase immediately in response to exercise. However, this increase is not usually associated with an increased risk of cardiovascular disease and should return to normal within 20 hours of the exercise being carried out.
Exercise and physical activity, however, are protective against the development of cardiovascular disease. Aerobic exercise such as walking, jogging, swimming and cycling and endurance training has been shown to be beneficial.
All these tests include hs-CRP. Select the test that suits your personal needs.
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 Viles-Gonzalez, J, F., Fuster, V and Badimon, J, J. (2004). Atherothrombosis: A Widespread Disease with Unpredictable and Life-Threatening Consequences. European Heart Journal: 25(14), pp 1197-1207.
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 Salas-Salvadó, J., Bulló, M., Babio, N et al. (2011). Reduction in the Incidence of Type 2 Diabetes with the Mediterranean Diet: Results of the PREDIMED-Resu Nutrition Intervention Randomized Trial. Diabetes Care: 34(1), pp 14-19.
 Zhang, H and Tsao, R. (2016). Dietary Polyphenols, Oxidative Stress and Antioxidant and Anti-Inflammatory Effects. Current Opinion in Food Science: 8, pp 33-42.
 Rauhe Mouridsen, M., Wendelboe Nielsen, O., Malchau Carlsen, C., Mattsson, N., Ruwald, M, H., Binici, Z and Sajadieh, A. (2014). High-Sensitivity C-Reactive Protein and Exercise-Induced Changes in Subjects Suspected of Coronary Heart Disease. Journal of Inflammation Research: 7, pp 45-55.
 Joyner, M, J and Green, D, J. (2009). Exercise Protects the Cardiovascular System: Effects Beyond Traditional Risk Factors. The Journal of Physiology: 587(pt23), pp 5551-5558.
This information has been medically reviewed by Dr Nicola Keay.
Nicola has extensive clinical and research experience in the fields of endocrinology and sport and exercise medicine. Nicky is a member of the Royal College of Physicians, Honorary Fellow in the Department of Sport and Exercise Sciences at Durham University and former Research Fellow at St. Thomas’ Hospital.
BA, MA (Cantab), MB, BChir, MRCP.