What is CRP – and why should you care about it?

C-reactive protein (CRP) is a protein found in the blood that is an accurate biomarker for inflammation in your body – both general inflammation, as well as cardiac-related inflammation.

It is measured by a simple blood test called high-sensitivity C-reactive protein (hsCRP). An otherwise healthy individual who has a high hsCRP level is four times more likely to have heart and blood vessel disease.

Is inflammation the single-most important risk factor for heart disease?

Although the connection between inflammation and cardiovascular disease risk has been known for two decades, the conventional approach for mitigating that risk remains focused on lowering cholesterol.

But an objective review of the research indicates that inflammation could be the single-most important risk factor for heart disease.

Findings from the Women’s Health Study that analyzed 28,000 healthy women found that hsCRP was a stronger predictor of heart disease than LDL cholesterol (the “bad” cholesterol).

Women in this study with the highest CRP level were four times more likely to have died from heart disease or to have suffered a heart attack or a stroke.1

In another large study, the Physicians’ Health Study of 18,000 healthy physicians, an elevated CRP level was associated with a 3-fold increase in heart attack risk.2 In a subgroup of these physicians, a high level of CRP was associated with peripheral artery disease (PAD), even in participants who had normal cholesterol levels.3 

All of this spawned the well-known JUPITER study of 17,800 healthy men and women. The JUPITER study found that giving statin drugs (normally prescribed to lower cholesterol) to study participants who had a normal LDL cholesterol level but a high CRP level, decreased the risk of heart attack and stroke.4

This was the first indication that statin drugs might work in some other way than decreasing cholesterol; i.e., statins might actually have an anti-inflammatory effect.

Where does this inflammation come from?

You don’t have inflammation in your body because of a statin deficiency. Instead, it can be associated with inflammatory conditions such as rheumatoid arthritis, periodontal disease, or inflammatory bowel disease.

Researchers are finding that an inflammatory condition that affects one part of your body – like joints in rheumatoid arthritis, gums in periodontal disease, and your GI tract in inflammatory bowel disease – can increase your risk for heart disease.5-7

A Mayo Clinic study found that the greater the severity of rheumatoid arthritis, the greater the risk for heart disease.8

Lifestyle factors, particularly diet, make a big contribution to the inflammatory burden in your body. Some of these risk factors include:

  • Eating fast food. One study found eating fast food one time a week or more increased CRP.9
  • Smoking – cigarettes, cigars, e-cigarettes
  • Being a couch potato
  • Eating sugary desserts
  • Drinking soda pop
  • Eating deep-fried foods
  • Eating foods containing partially hydrogenated oils (read the label!)

If you do have signs of high inflammation in your body, then what can you do about it?

So many conditions – yet one central causative factor – inflammation. The silver lining is that anything you can do to quench the inflammation should help you in multiple ways. So what can you do?

Eat an anti-inflammatory diet, which includes:

  • Fatty fish high in omega-3 fatty acids at least twice a week (trout, salmon, sardines, anchovies, mackerel)9
  • Olive oil10 – for sautéing and in salad dressings
  • Liberal use of anti-inflammatory spices – like turmeric, ginger, cayenne, cinnamon, clove, sage, and rosemary
  • Plenty of green, yellow, and orange vegetables9
  • Dark red, blue, and purple berries9
  • Avoiding foods you know you are allergic to, since allergic reactions can cause inflammation

What do these dietary factors have in common? They are a huge part of the Mediterranean Diet, which has been consistently shown to decrease CRP when it’s adhered to.11 For more information on the Mediterranean Diet, check out this blog post.

Activities to improve CRP levels

  • Regular, moderately intense exercise has been shown to lower CRP. For example, one 12-week study in women who had type 2 diabetes found that aerobic exercise – starting with 8 minutes of jogging and 8 minutes of running and working up to 32 minutes – significantly decreased CRP and other biomarkers of inflammation.12
  • Engage in stress-reducing activities – because stress can increase inflammation in your body. Yoga and Pilates are great options to lower stress. One study found that one hour of yoga daily, six days a week for three months, lowered CRP.13
  • Reduce environmental stress by exercising indoors in areas free of smoke, smog, and pollution.

Who should test their CRP level?

Testing to know your CRP level is particularly indicated for individuals who have other risk factors for heart disease, including:

  • Men age 45 or older and women age 55 or older
  • Current smokers or a smoker in the previous five years (one study found it took five years for inflammatory markers to return to normal after stopping smoking)14
  • A family history of early heart disease (in a male first-degree relative less than age 55 or in a female first-degree relative less than age 65)
  • Long-term systolic blood pressure over 140 mm Hg or being on a blood pressure medication
  • A low level of high-density lipoprotein (HDL or “good”) cholesterol; i.e., less than 40 mg/dL
  • Diabetes, prediabetes, elevated fasting blood sugar, and/or elevated HbA1c (a measure of long- term blood sugar levels)

Although the hsCRP test does not specifically diagnose any disease, having an elevated CRP level is a sign of inflammation that can be a risk factor for a number of chronic adverse health conditions, including heart disease.

Thorne’s Heart Health At-Home Test uses a simple finger-stick blood-spot test to measure CRP levels (using hsCRP technology), along with levels of triglycerides, insulin, HbA1C, and a cholesterol panel – all in the comfort of your own home.


References

  1. Ridker P. High-sensitivity C-reactive protein and cardiovascular risk: rationale for screening and primary prevention. Am J Cardiol 2003;92(4B):17K-22K.
  2. Blood tests to determine risk of coronary artery disease: test details. https://my.clevelandclinic.org/health/diagnostics/16792-blood-tests-to-determine-risk-of-coronary-artery-disease/test-details [Accessed 3.6.19]
  3. Ridker P, Cushman M, Stampfer M. Plasma concentration of C-reactive protein and risk of developing peripheral vascular disease. Circulation 1998;97(5):425-428.
  4. Ridker P, Danielson E, Fonseca F. Rosuvastatin to prevent vascular events in men and women with elevated C-reactive protein. N Engl J Med 2008;359(21):2195-2207.
  5. Rheumatoid arthritis and cardiovascular disease. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3890244/ [Accessed 3.6.19]
  6. Link between heart attacks and inflammatory bowel disease. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1160597/ [Accessed 3.6.19]
  7. Gum disease and heart disease: the common thread. https://www.health.harvard.edu/heart-health/gum-disease-and-heart-disease-the-common-thread [Accessed 3.6.19]
  8. Rheumatoid arthritis and heart disease: Mayo Clinic studies shed light on dangerous connection. https://newsnetwork.mayoclinic.org/discussion/rheumatoid-arthritis-and-heart-disease-mayo-clinic-studies-shed-light-on-dangerous-connection/ [Accessed 3.6.19]
  9. Yeo R, Yoon S, Kim O. The association between food-group consumption patterns and early metabolic syndrome risk in non-diabetic healthy people. Clin Nutr Res2017;6(3):172-182.
  10. Souza P, Marcadenti A, Portal V. Effects of olive oil phenolic compounds on inflammation in the prevention and treatment of coronary artery disease. Nutrients 2017 Sep 30;9(10). pii: E1087. doi: 10.3390/nu9101087.
  11. Whalen K, McCullough M, Flanders W, et al. Paleolithic and Mediterranean Diet pattern scores are inversely associated with biomarkers of inflammation and oxidative balance in adults. J Nutr 2016 Jun;146(6):1217-1226.
  12. Saghebjoo M, Nezamdoost Z, Ahmadabadi F, et al. The effect of 12 weeks of aerobic training on serum levels of high sensitivity C-reactive protein, tumor necrosis factor-alpha, lipid profile and anthropometric characteristics in middle-age women patients with type 2 diabetes. Diabetes Metab Syndr 2018;12(2):163-168.
  13. Shete S, Verma A, Kulkarni D, Bhogal R. Effect of yoga training on inflammatory cytokines and C-reactive protein in employees of small-scale industries. J Educ Health Promot 2017;6:76.
  14. Smoking and inflammation. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1160597/ [Accessed 3.6.19]