Some risk factors for heart disease cannot be changed.

These include getting older (men over 45, women over 55), having a family history of early heart disease, being male (although women’s risk rises after menopause), and your ethnic background. People of Aboriginal or Torres Strait Islander heritage, and those from South Asian or Pacific Islander backgrounds, are at higher risk.

The good news is that most of the risk comes from things you can change.

A very large worldwide study (the INTERHEART study) showed that nine lifestyle and health factors together explained over 90% of the risk of having a heart attack, across all ages and backgrounds.

The biggest contributor is abnormal cholesterol. High LDL (“bad cholesterol”) especially strongly increases risk.

Smoking is another major risk factor — both current and past smoking increase heart risk, as does vaping.

Psychological stress, including long-term stress, anxiety, or depression, also raises risk.

Carrying extra weight around the middle (a large waistline or high BMI) makes a big difference, especially when combined with other factors.

High blood pressure (anything persistently above 140/90 mmHg, or above 130/80 mmHg in people at higher risk) puts extra strain on the heart and blood vessels.

A poor diet that is low in fruit and vegetables but high in saturated fats, salt, and sugars increases risk.

Lack of regular exercise (less than 150 minutes of moderate activity per week) is another contributor.

Type 2 diabetes raises the risk of heart attack significantly, especially if blood sugars are not well controlled.

Finally, alcohol has a complicated effect. Small amounts (up to 10 drinks per week) may slightly reduce risk, but higher intakes increases risk of death. Binge drinking greatly increases overall heart and health risks.

✅ Key message for patients:

While you can’t change your age, family history, or background, you can do a lot to lower your risk. Quitting smoking, eating well, being active, maintaining a healthy weight, managing stress, keeping blood pressure, cholesterol, and diabetes under control, and being careful with alcohol are all powerful steps to protect your heart.