New study shows 99% of heart attacks have these warning signs people miss

Heart disease continues to be one of the world’s biggest health challenges. According to the World Health Organization, cardiovascular diseases (CVDs) claim nearly 17.9 million lives every year, making them the leading cause of death globally. These diseases affect the heart and blood vessels, and in over 80 percent of cases, the outcome is fatal heart attacks or strokes. A recent large-scale study by researchers in Korea and the United States shows that heart attacks and strokes do not just happen suddenly. Almost all cases are linked to one or more risk factors that were present earlier, even if they were not serious enough for a diagnosis. So, how can we spot these signs early and reduce the risk of heart disease?

What did the new study find about heart disease risks?

For this research, scientists analyzed the medical records of more than 9 million adults in South Korea and nearly 7,000 adults in the United States. Participants were tracked for up to 20 years, with repeated measurements of blood pressure, cholesterol, blood sugar, and smoking exposure. The researchers focused on four well-known risk factors using the American Heart Association’s guidelines:

• Blood pressure: 120/80 mm Hg or higher, or on treatment
• Fasting glucose: 100 mg/dL or higher, diabetes diagnosis, or treatment
• Tobacco use: current or past smoking history
• Cholesterol: 200 mg/dL or higher, or on treatment

The results, published September 29 in the Journal of the American College of Cardiology, directly challenge the idea that heart attacks often strike people without warning. Instead, the data revealed that more than 99 percent of individuals who experienced a heart attack, stroke, or heart failure had at least one non-optimal risk factor before their event. High blood pressure emerged as the biggest culprit, affecting over 95 percent of Korean participants and more than 93 percent of US participants. The study is a clear warning that subtle shifts in blood pressure, cholesterol, or sugar levels should never be ignored.

What are the warning signs of heart disease that most people miss?

When people think of heart attacks, they imagine sudden chest pain or severe breathlessness. But the body often shows warnings long before that moment. These overlooked signs can include:

• Mildly elevated blood pressure or cholesterol, even without a diagnosis
• Increased blood sugar, sometimes years before diabetes develops
• Unexplained exhaustion, fatigue, or sudden sweating
• Digestive discomfort like indigestion or nausea
• Pain or tightness in the arm, jaw, neck, or back
• Palpitations or irregular heartbeats
• Cramping in the calves while walking (possible circulation issue)
• A tight throat or feelings of heaviness in the chest

What are the risk factors of heart disease?

Heart disease does not happen overnight, it builds over years of unhealthy habits and exposures. The most common risk factors include:

• Smoking or exposure to secondhand smoke
• Sedentary lifestyle with little exercise
• Excess body weight or obesity
• Excessive alcohol consumption, which raises blood pressure
• Persistently high blood pressure
• Poor diet rich in saturated and trans fats
• Uncontrolled diabetes
• Chronic stress or emotional strain
• A family history of heart disease
• Ageing (with risks increasing after 50)
• Higher risk in men compared to women at younger ages

The presence of even one of these factors can elevate heart disease risk, and combinations increase it significantly.

How can you spot these risk factors before it is too late?

The best way to combat heart disease is to identify its risks before they become dangerous. Dr Rahul Gupta, Cardiologist, Gleneagles Hospital, advises regular health screenings for blood pressure, cholesterol, and blood sugar, even if you feel healthy. Numbers slightly above normal should never be dismissed, as they can silently damage blood vessels and the heart over time.

Mental health matters too. Chronic stress, anxiety, and depression can raise inflammation and blood pressure, putting the heart under constant strain. Watch for early lifestyle patterns, such as weight gain, fatigue, or shortness of breath with light activity. These are not just normal ageing, but possible warning signs.

Routine check-ups, preventive lab tests, and a proactive approach to lifestyle can spot problems early. Taking small steps now can stop risk factors from growing into life-threatening conditions later.

How to reduce heart disease risk?

Most heart attacks are preventable with consistent care and lifestyle choices. Here is what cardiologists recommend:

• Eat healthy: Follow a Mediterranean or DASH diet, rich in fruits, vegetables, nuts, and lean proteins.
• Stay active: At least 150 minutes of moderate activity weekly keeps the heart strong.
• Manage stress: Meditation, deep breathing, or even journaling lowers long-term strain.
• Sleep well: 7–8 hours per night gives the body time to heal.
• Quit smoking: Quit it and avoid secondhand smoke. Limit alcohol intake as well.
• Stay hydrated: Morning hydration helps promote better circulation after overnight dehydration.
• Regular screening: Get regular tests for blood sugar, high cholesterol, and blood pressure, even if you feel fine.

With these tips, you can lower your heart attack risk!