Heart disease is a primary cause of mortality in the United States. Historically, risk assessment for heart disease has largely relied on cholesterol levels, a practice established in the 1950s.
Recent evidence suggests that C-reactive protein (CRP), a biomarker indicating low-grade inflammation, may be a more significant predictor of heart disease risk than cholesterol. Consequently, the American College of Cardiology issued new recommendations in September 2025 for universal screening of C-reactive protein levels in all patients, in addition to cholesterol measurements.
Understanding C-Reactive Protein
C-reactive protein is produced by the liver in response to various conditions, including infections, tissue damage, chronic inflammatory states (such as autoimmune diseases), and metabolic disturbances (like obesity and diabetes). It functions as a marker for immune system activation, or inflammation, within the body.
CRP levels can be determined through routine blood work. A level below 1 milligram per deciliter (mg/dL) is associated with minimal inflammation, which is considered protective against heart disease. Conversely, an elevated CRP level exceeding 3 mg/dL indicates increased inflammation and a corresponding elevated risk for heart disease. Approximately 52% of Americans exhibit elevated C-reactive protein levels.
Research indicates that C-reactive protein is a more significant predictive marker for heart attacks and strokes than low-density lipoprotein (LDL) cholesterol, often referred to as 'bad' cholesterol, and lipoprotein(a), a genetically inherited biomarker. One study reported that C-reactive protein's predictive capacity for heart disease is comparable to that of blood pressure.
The Role of Inflammation in Heart Disease
Inflammation contributes to all stages of atherosclerotic plaque development in the arteries, a condition that can lead to heart attacks and strokes. Upon damage to a blood vessel, from factors such as high blood sugar or cigarette smoke, immune cells infiltrate the affected area. These immune cells then engulf cholesterol particles circulating in the bloodstream, leading to the formation of a fatty plaque within the vessel wall.
This process can occur over decades. Eventually, immune mediators may cause the rupture of the plaque's encapsulating cap, initiating a blood clot. This clot obstructs blood flow, leading to oxygen deprivation in surrounding tissues and ultimately causing a heart attack or stroke. This mechanism suggests that the immune system facilitates critical steps in the progression of heart disease, with cholesterol being one component.
Lifestyle Factors and C-Reactive Protein Levels
Lifestyle choices can significantly influence the liver's production of C-reactive protein. Dietary fiber (found in beans, vegetables, nuts, seeds), berries, olive oil, green tea, chia seeds, and flaxseeds have been shown to reduce CRP levels.
Weight loss and consistent physical exercise are also associated with reduced C-reactive protein levels.
Additional Biomarkers for Heart Disease Risk
While C-reactive protein is a significant indicator, cholesterol remains relevant for assessing heart disease risk. However, risk is more accurately determined by the number of 'bad' cholesterol particles rather than their total mass. A higher particle count correlates with increased risk.
Apolipoprotein B, a blood test measuring the number of cholesterol particles, is considered a more accurate predictor of heart disease risk than total LDL cholesterol measurements. Like CRP and cholesterol, apolipoprotein B levels are influenced by lifestyle factors such as exercise, weight loss, and diet. Nutrients including fiber, nuts, and omega-3 fatty acids are associated with a decreased number of cholesterol particles, while increased sugar intake is linked to a higher number.
Lipoprotein(a), a protein associated with cholesterol particles, is another marker that can predict heart disease with greater accuracy than cholesterol levels. Its presence may increase the 'stickiness' of cholesterol particles, making them more prone to entrapment in atherosclerotic plaques. Unlike other risk factors, lipoprotein(a) levels are genetically determined and are not influenced by lifestyle, requiring only a single lifetime measurement.
Comprehensive Heart Disease Prevention
Heart disease development results from the interaction of multiple risk factors over time. Effective prevention involves a holistic approach beyond solely dietary cholesterol restriction. A comprehensive risk assessment, including LDL cholesterol, C-reactive protein, apolipoprotein B, and lipoprotein(a) levels, can inform and reinforce a long-term commitment to preventive measures. These include maintaining a balanced diet, engaging in regular physical activity, ensuring adequate sleep, managing stress effectively, achieving a healthy weight, and abstaining from smoking.