You probably know your height and weight and may even have your typical blood pressure readings and most recent cholesterol scores memorized. But there’s another number that is even more important for assessing your risk of heart attack or stroke.

The coronary artery calcium (CAC) score measures the amount of calcified plaque you have in those arteries, which is important because coronary plaque is the main underlying cause of — or precursor to — events such as heart attacks and strokes.

Your calcium score can range from zero to infinity and is proportional with your risk of having such an event up to 15 years. People with no coronary artery calcium — even those with risk factors like diabetes, obesity or advanced age — have low absolute risk of heart attack or stroke events. In contrast, people with high CAC scores have an elevated risk of heart attack or stroke, even if they’ve never had any symptoms of heart disease and appear to be the picture of health.

A calcium test may be the most accurate predictor, or biomarker, of heart attack or stroke risk to date. But not everyone who could benefit from one knows about it. Here’s what you need to know about this test, why you should get one and what the results might mean.

The buildup of plaque can clog your arteries, which will slow your blood flow and prevent certain areas of your heart from receiving proper levels of oxygen. The plaque deposits also can cause a blood clot which may trigger a heart attack. Because the CAC score gives a measure of the burden of plaque in the coronary arteries, determining your calcium score is a very useful way to predict the likelihood of a future heart attack or stroke.

An estimated 15% of individuals assumed to be at low risk have a relatively high amount of calcified plaque and are therefore at higher risk of having an event than anticipated. And about 30%-50% of patients in traditional high-risk categories have no plaque (a CAC score of zero), which puts them at low risk of events.

“With this test, we can stop guessing about the condition of your arteries,” says Dr. Miguel Cainzos-Achirica, preventive cardiologist at Houston Methodist Hospital. “Instead, we can see if there’s any plaque there, and if so, how much.”

It is recommended that males and females over the age of 40 regardless of lifestyle, and people of any age who have a history of heart disease, smoking, diabetes or obesity get a cardiac calcium score test, and repeat the test annually to monitor their score. You can schedule a test through your primary care physician or cardiologist. Since February is heart health month, the test usually only costs between $25-$99!

What do the scores mean?
0: You have no calcified plaque. Your risk of heart attack or stroke event is low — not zero — but the lowest among your group.
1-10: You have a small amount of plaque. Prevention strategies should be discussed in order to keep your risk on the lower end, potentially with a focus on lifestyle changes.
11-100: You have some coronary plaque and a moderate chance of heart attack. Your doctor may recommend treatments in addition to lifestyle changes.
101-400: Your chance of having a heart attack is moderate to high. Your health professional will want you to consider intensive healthy lifestyle changes and, possibly, start additional treatments.
Over 400: You have a large amount of plaque, and your chance of heart attack or stroke event is high. Your health professional will want you to consider intensive healthy lifestyle changes and functional interventions to reduce your risk of heart attack or stroke.

What can I do to affect my score?
Successful lifestyle strategies like regular Chiropractic care, healthy diet, nutritional supplementation and exercise are all shown to lower risks of heart attack and stroke events.

Research has shown that an annual CAC score progression of less than 15% decreases the chance of heart attack or stroke by 97% regardless of the baseline score! So the idea here is to focus on halting plaque progression through lifestyle management strategies.

So this February, start a new health habit and get a coronary calcium score test so you can establish your baseline, and then focus on creating and maintaining a healthy lifestyle