“If I had to pick just one test to predict how healthy somebody was, it would be the C-reactive protein (CRP) test,” says Dr. Mark Liponis, M.D., corporate medical director at Canyon Ranch in Lenox, Mass. “It’s a better indication than cholesterol, blood pressure, family history—even your genes.”
CRP is mainly produced by your white blood cells, liver cells and fat cells. It is a highly sensitive and easily measured biomarker of chronic inflammation—a state when the immune system uses its natural defenses to fight germs, but also causes damage to healthy areas of the body instead of protecting them from harm. Think of CRP sort of like a crystal ball: Its presence can be one of the first things that hints at an underlying health problem. And because inflammation plays a role in the development of a myriad long-term health concerns—from heart attack and stroke to diabetes, macular degeneration to cancer and more—your CRP level can, essentially, foretell if such issues are likely to strike you in years to come. In fact, adults over age 50 who have a high level of CRP in their blood have a 50 percent greater chance of heart attack, stroke and cardiac death than those with low CRP (all other risk factors considered). A CRP blood test can actually predict heart attack and stroke better than any other lab test available.
Who Has High C-reactive Protein?
Most people in good health shouldn’t have elevated CRP levels in their blood, but about one-third of Americans do—and feeling good isn’t enough reason to think you are not one of them. While chronic inflammation can contribute to noticeable concerns like digestive issues, allergies and skin conditions, many people who have elevated CRP often have no obvious symptoms at all.
Reasons for elevated CRP vary, and more than one may be at play. Two of the most common ones are being overweight and not exercising, but not sleeping well also plays a role: “When you rest, your immune system recharges and recollects itself. If you’re not getting proper sleep, you’re not doing that,” says Dr. Liponis. “Smoking, having asthma, not eating a healthy diet all up CRP level, too, as does feeling chronically worried, nervous, hostile or depressed.” Hormonal birth control or hormone replacement therapy use can also increase CRP.
It’s important to remember that high CRP is not a detection of disease. “It’s a precise measure of how active your immune system is—a measure of health,” says Dr. Liponis. While the blood test that checks for this cannot tell you where the inflammation is coming from, it can tell you that even mild forms of it exist. This can put you and your doctor on the right path to finding the cause—and a way to address it—at what’s hopefully an early stage of inflammation’s progression.
While the American Heart Association (AHA) states that it’s a good idea to consider a CRP evaluation in your mid-30s, it also points to good evidence that CRP levels in your teens and 20s are very predictive of levels later in life—and the experts at Canyon Ranch agree.
CRP is part of the normal blood tests we do for guests who seek our medical services, but it is not likely part of routine testing done by your doctor. Ask your physician about adding this to your annual lab work. The best test is the high-sensitivity CRP, also known as the cardio CRP, which is more accurate than the standard CRP. The AHA notes that levels less than 1 mg/L are desirable; levels between 1 and 3 mg/L are indicative of moderate risk; levels of 3 mg/L or more suggest a large elevated risk. “Personally, I like people’s levels to be less than 0.7,” notes Dr. Liponis.
If your results are not where you and your doctor want them to be, work together to identify the best ways to improve them. Losing weight, for example, can significantly lower CRP (even if it is achieved by way of gastric bypass). Our other tips on reducing inflammation can help, too.