The aim of primary prevention is to reduce the risk of first-ever stroke in asymptomatic people. Seven factors are regarded as potentially modifiable risk factors for vascular diseases: high blood pressure, high cholesterol, smoking, excessive or heavy regular alcohol consumption, physical inactivity, overweight and dietary factors. The strategy in primary prevention is to lower stroke risk attributed to these factors through education, lifestyle changes and medication. Non-modifiable risk factors arising from diseases such as atrial fibrillation or diabetes mellitus can be lowered by controlling and treating the underlying disorder. Targets of primary stroke prevention can be the entire population or high-risk – but stroke-free – individuals partly suffering from disorders such as hypertension or diabetes mellitus.
Stroke prevalence has been associated with individual lifestyle factors (e.g. smoking, exercise, body mass index (BMI), alcohol consumption) in several studies. Healthy lifestyle in general was considered in one large prospective cohort study of healthy women. In this study, healthy lifestyle, consisting of abstinence from smoking, low-normal body mass index, moderate alcohol consumption, regular exercise and healthy diet, was found to be associated with a reduction in ischemic stroke (RR 0.3; 95% CI 0.1–0.6) . Using the data of two large cohort studies, the Nurses' Health Study (71 243 women) and the Health Professionals Follow-up Study (43 685 men), Chiuve et al.  defined a low-risk lifestyle score based on the five lifestyle components non-smoking, moderate activity ≥ 30 min/day, healthy diet, body mass index < 25 kg/m2 and modest alcohol consumption (men 5–30 g/day, women 5–15 g/day).