Consuming plenty of low-fat dairy foods like milk and yogurt appears to reduce the risk of having a stroke.
Swedish researchers followed nearly 75,000 middle-aged and older men and women over a period of 10 years. The study began in 1997 when participants completed a questionnaire about their lifestyle, diet and exercise habits, body mass index, work, and education. All were free of any history of heart disease, stroke, or cancer at the time.
High-fat dairy foods contain more saturated fat, which can increase LDL or "bad" cholesterol levels and, in turn, lead to clogging of the arteries that supply blood to the heart and brain.
Over the next ten years, researchers followed the incidence of stroke using the Swedish Hospital Discharge Registry. There were 4,089 cases of stroke reported including 3,159 cerebral infarctions, 583 hemorrhagic strokes, and 347 cases of unspecified strokes. A cerebral infarction occurs when there is a blockage in a vessel that supplies blood to the brain, and a hemorrhagic stroke is caused by a rupture of a blood vessel in the brain.
High blood pressure is a risk factor for stroke. About one-third of adult Americans have high blood pressure, but only about half have their blood pressure under control. The DASH diet (Dietary Approaches to Stop Hypertension) emphasizes the consumption of low-fat dairy products and recommends two to three servings a day, depending on calorie intake.
The USDA's Dietary Guidelines for Americans recommends three servings of dairy foods a day, and advises low-fat products.
According to the study authors, the benefits of low-fat dairy foods on stroke risk are likely due to the presence of vitamin D and the minerals calcium, potassium, and magnesium.
There are other risk factors for stroke besides high blood pressure and diet. Other risk factors include smoking and lack of exercise. A healthy diet combined with smoking cessation, increased exercise, and good blood pressure control can reduce the risk of stroke.