Previous studies on the effect of dietary intake of elements such as magnesium, calcium, potassium and sodium on stroke risk have provided conflicting information. To verify these data, researchers from the Karolinska Institute in Sweden studied the relationship between supplementation of the above elements and stroke risk in a group of 26556 Finnish cigarette smokers (men), aged 50 to 69 years. The amount of supplemented elements in the diet was assessed using an accurate and validated questionnaire.