CRP is an inflammatory marker produce by the liver. It is more predictable than any other parameters for all chronic and degenerative disease process especially blood vessel disease with manifestation of coronary heart disease, diabetic foot gangrene and stroke. Inflammation is the core or triggering process to free radicals. There are many factors accelerate inflammation and many of the factors are over-lapping with factors that accelerate free radicals. They are the core process for aging related disorders such as coronary heart disease, stroke, cancer, osteoarthritis, macular degeneration, polyneuropathy, skin wrinkle, etc.
Acute inflammation is easy to understand. Example of acute inflammation are boil, bruise and bump of injury, abscess, gouty arthritis, boil, stye, septic arthritis just to name a few. In the examples, acute inflammation is good to mobilize immune cells and trigger immune cascade mechanism to fight infection and get rid of the causes. C-Reactive Protein produce by the liver in reaction to inflammation, therefore it is a blood test for inflammation marker. The level is very high in reaction to acute inflammation especially bacterial infection. Chronic and recurrent of acute inflammation is also a risk factor for chronic and degenerative diseases.
However, here we are concerned with chronic low level, sub-clinical inflammation. Inflammation is the true cause for coronary heart disease.
Death by inflammation, NOT by cholesterol. Cholesterol is just innocent by-stander for blood vessel disease. Cholesterol is just a marker and it is a lousy marker.
Best level for CRP is below 1 mg/L. The level above 3 mg/L is very high risk for coronary disease. In fact it is a cause of heart disease. The risk is high regardless of your cholesterol level and can be 4.5 times increase heart attack rate if CRP level persistently above 3 mg/L.