What It Means to Have High C-Reactive Protein Levels

When C-reactive protein (CRP) is high, it's a sign of inflammation in the body. While there is no widely accepted definition of "normal" CRP levels, values above 1 milligram per liter are generally considered to be high. Having elevated CRP levels over time is associated with an increased risk of cardiovascular disease.

High CRP levels are also commonly related to medical conditions—such as an infection like COVID-19, a chronic inflammatory condition like rheumatoid arthritis, and some cancers.

This article explains what it means for your C-reactive protein to be high. It will cover what CRP blood tests are used for, possible causes for elevated CRP levels, and the medication and lifestyle changes that can treat high CRP.

Why Is a C-Reactive Protein Test Done?

Experts do not recommend that providers routinely test CRP levels. You may need to have your CRP levels checked if your healthcare provider thinks you could have an infection or another condition that causes inflammation.

CRP is made in the liver in response to the activity of white blood cells, which fight infection and inflammation in the body. When white blood cells are more active (for example, because they’re fighting an infection), more CRP is made. That’s why CRP can be a biomarker for inflammation, and why the test can be used to help diagnose inflammatory conditions. CRP levels are also used to screen for cardiovascular risk.

In most healthy adults, the normal CRP range is 0.3 milligrams per deciliter (mg/dL) or less. Most providers will consider a CRP level that’s higher than 10 mg/L to be abnormal.

What Does a High CRP Level Mean?

If your CRP levels are high, your provider will consider how much higher than the normal range they are. Your levels might be moderately, markedly, or severely elevated. The level of elevation can provide clues about what might be causing the levels to be abnormal. The following conditions may be associated with these elevation levels:

Mild Elevation (3-10 mg/L)

• Obesity
• Pregnancy
• Smoking
• Diabetes
• Periodontal disease
• Mild viral infections (e.g., the common cold)

Moderate (over 10 mg/L) 

• Autoimmune disorders (e.g., lupus, rheumatoid arthritis inflammatory bowel disease) 
• Heart attack
• Pancreatitis 
• Respiratory infections (e.g., acute bronchitis) 
• Some cancers (e.g., liver, lung, colon, breast, and endometrium)
  

Marked Elevation (over 100 mg/L)

• Serious bacterial or viral infections
• Whole-body (systemic) blood vessel inflammation (vasculitis) 
• Major traumas or injuries
  

Severe Elevation (over 500 mg/L) 

• Serious bacterial infections (sepsis) 

How Long Levels Stay High

How long your levels are high also matters. When CRP levels stay elevated for a long time, it can be a sign that there is chronic inflammation in the blood vessels in your body. 

Low-grade inflammation contributes to the deposit of fat and other substances in the walls of your arteries (atherosclerosis). The build-up of fat can narrow the arteries that bring the heart blood, causing coronary artery disease (CAD). Over time, this can lead to heart attack, stroke, or heart failure—even for people with high CRP levels who have no signs or symptoms of active inflammation.

A study of 376 people found that 210 of them diagnosed with CAD had elevated CRP levels when compared with 166 people who did not have CAD. The CRP level increased in step with the degree of blood vessel damage as seen on an imaging test used to visualize blood flow through the heart (coronary angiography).

C-Reactive Protein Treatment

There are several risk factors that contribute to high CRP levels, many of which are things you might be able to change. For example, elevated CRP levels are almost always linked to certain risk factors for heart disease, including:

• Smoking
• Obesity
• Inactive lifestyle
• High cholesterol
• High blood pressure
• Diabetes
• Metabolic syndrome (a combination of high blood pressure, high blood sugar, abnormal lipid levels, and excess abdominal fat)

It’s not clear how much lowering your CRP level can help lower your risk of heart disease or other health problems. Talk to your healthcare provider about your heart disease risk factors and what can be done to address them and your CRP levels.

In general, having high CRP levels can be a sign that your health might benefit from making some changes.

Lifestyle Changes

You do not necessarily need medication to lower your levels of CRP. You can make some lifestyle changes that will help lower the levels of inflammation in your body.

You might be able to reduce your CRP without drugs by:

• Increasing your aerobic exercise (e.g., running, fast walking, cycling)
• Quitting smoking
• Getting to a weight that supports your health
• Eating a heart-healthy diet (e.g., eating plenty of anti-inflammatory foods such as salmon, tuna, and plant-based proteins, avoiding processed meat, consuming omega-3 fatty acids or monounsaturated fatty acids, and including more fresh fruits and vegetables)
  
• Reducing stress

Some of these strategies can also help address other heart disease risk factors you may have, such as obesity and high blood pressure.

Statins

Statins are drugs that lower cholesterol. Studies have shown that they can reduce CRP levels by 13% to 50%. Statins can also greatly reduce the risk of heart attack and stroke in people with high CRP levels who do not have any other signs or symptoms.

These common statin medications that may help bring down CRP levels and reduce related cardiac risks:

• Crestor (rosuvastatin)
• Lipitor (atorvastatin)
• Mevacor (lovastatin)
• Pravachol (pravastatin)
• Zocor (simvastatin)

If you have high CRP levels—especially if you have one or more additional risk factors for heart disease—you may want to talk to your provider about statin therapy. 

Does Aspirin Help?

By itself, aspirin does not specifically lower CRP levels. However, daily aspirin therapy is sometimes used as a heart attack and stroke prevention measure. However, the risks of taking aspirin every day are sometimes higher than the possible preventive benefits, so it’s important to talk to your provider about whether the treatment would be safe for you. 

People with high CRP may benefit from aspirin therapy more than people with normal CRP levels. For example, it might be useful for people with elevated CRP levels who are at a higher risk of heart disease or who have already had a cardiac event.

Aspirin therapy is not safe and effective for everyone. Always talk to your healthcare provider before taking low-dose aspirin for daily therapy.

Summary

High CRP levels mean you have inflammation in your body. Inflammation can be a sign of infections, inflammatory conditions like arthritis, and some forms of cancer. CRP is also a major indicator of your heart disease risk, but it’s not known whether high CRP raises the risk for heart disease or if having heart disease raises CRP. 

If your CRP levels are high, talk to your provider about what you can do to bring them down. You might be able to lower your CRP levels naturally by changing your diet, but you may need help from a medical treatment like statin medications.