8 September 2026 Punjab Khabarnama Bureau : Finding calcium in the arteries of the heart can sound alarming, but a coronary artery calcium (CAC) score does not directly tell you whether an artery is blocked.
Instead, calcium is a marker of atherosclerotic plaque—the buildup of fatty material, cholesterol and other substances in artery walls. The higher the calcium score, the greater the evidence of coronary artery disease and future cardiovascular risk.
Calcium Is a Marker of Plaque, Not a Blockage Measurement
A coronary calcium scan is a specialised CT scan that detects calcium deposits within plaque in the coronary arteries.
A higher score generally indicates a greater amount of calcified plaque and a higher risk of heart disease. However, the score does not show exactly how much an artery has narrowed or whether blood flow is significantly restricted.
This distinction is important because two people with similar calcium scores can have very different degrees of artery narrowing.
Can You Have a High Calcium Score Without a Major Blockage?
Yes.
A high CAC score indicates a substantial burden of calcified plaque, but that does not necessarily mean there is a severe obstruction requiring a stent.
A recent report highlighted a patient with a calcium score of around 900 who had plaque but only relatively minor blockages and was managed with medication and risk-factor control.
Can You Have a Serious Blockage With a Zero Calcium Score?
Surprisingly, yes.
A zero calcium score means no detectable calcified plaque, but it does not completely rule out coronary artery disease because some plaque can be non-calcified.
A recently reported case involved a younger man with diabetes who had a zero calcium score but was found to have a severe coronary narrowing. Published medical literature has also documented significant coronary stenosis despite a zero CAC score.
What Does a Calcium Score Tell You?
In general, the CAC score is used as a marker of cardiovascular risk:
- 0: No detectable coronary calcium and generally a low near-term risk.
- 1–99: Evidence of some calcified plaque.
- 100–300: Moderate plaque burden and increased risk.
- Above 300: More extensive calcification and substantially higher cardiovascular risk.
These numbers are risk indicators, not direct measurements of the percentage of artery blockage. Doctors interpret them alongside age, cholesterol, blood pressure, diabetes, smoking history, symptoms and other factors.
Why CT Coronary Angiography Can Be Different
A CT coronary angiography (CCTA) provides much more anatomical information than a calcium-score scan.
It can help doctors see the coronary arteries and identify both calcified and non-calcified plaque, as well as assess whether there is narrowing of the artery.
This is why someone with symptoms or other risk factors may need additional evaluation even when the calcium score is low or zero.
Does Eating Calcium Cause Calcium in the Arteries?
Not necessarily.
The calcium detected in coronary arteries is part of the biological process of atherosclerotic plaque formation and is not simply calcium from food or supplements being deposited directly into the arteries.
Research and medical guidance distinguish dietary calcium from the calcification process seen in coronary artery disease.
What About Vitamin D and Calcium Supplements?
People who receive a high calcium score sometimes worry that calcium supplements or vitamin D caused the deposits.
However, coronary calcification is primarily associated with the development of atherosclerotic plaque and cardiovascular risk factors rather than simply consuming calcium-rich foods.
Whether someone should take calcium or vitamin D supplements should be decided based on their individual medical needs rather than a calcium score alone.
What Happens After a High Calcium Score?
A high score does not automatically mean that a person needs an angioplasty or stent.
Doctors may instead focus on reducing cardiovascular risk through measures such as cholesterol management, blood-pressure control, diabetes management, smoking cessation, physical activity and dietary changes.
Depending on symptoms and overall risk, further tests may be recommended to determine whether significant narrowing is present.
Chest Pain Should Not Be Ignored
A calcium score is a risk-assessment tool, not a substitute for evaluation of symptoms.
People experiencing new or worsening chest pain, pressure, shortness of breath, sweating, nausea or pain spreading to the arm, jaw or back should seek urgent medical attention rather than relying on a previous calcium-score result.
The Bottom Line
Calcium in the coronary arteries means there is evidence of calcified plaque and increased cardiovascular risk—but it does not automatically mean the artery is blocked.
Likewise, a calcium score of zero is reassuring but cannot completely exclude non-calcified plaque or significant coronary disease, particularly in people with symptoms or important risk factors.