Stroke: Nutritional Considerations

The role of dietary factors in stroke is apparent from the disorder’s pathophysiology. Because ischemic strokes are caused by atherosclerosis, they are more common in the presence of high blood cholesterol concentrations, which, in turn, are strongly linked to dietary saturated fat and cholesterol and a low fiber intake, among other contributors to cardiovascular risk. Similarly, hypertension contributes to both ischemic and hemorrhagic stroke, so diets that are high in saturated fat or sodium or low in potassium would tend to increase risk. A diet high in potassium, low in sodium, and rich in vegetables, fruits, cereal fiber, and whole grains is probably ideal for reducing stroke risk (Ding 2006).

In epidemiological studies, the following factors are associated with reduced stroke risk:

Reduced dietary fat and cholesterol. Individuals with higher blood cholesterol concentrations tend to have higher stroke risk.^13,14 In women with diabetes sampled from the Nurses’ Health Study, higher intakes of saturated fat and cholesterol–which raise blood cholesterol concentrations–were related to an increased risk for cardiovascular disease (CVD), including stroke.¹⁵

Diets rich in fruits, vegetables, and whole grains. Higher intakes of fruits and vegetables not only reduce fat and cholesterol intake, but also are associated with reduced risk for stroke.¹⁶ These foods provide carotenoids, vitamin C, vitamin E, and folate, all of which have been associated with reduced stroke risk in epidemiologic studies.^17–22 High intake of cereal fiber was associated with lower risk for both total and hemorrhagic stroke risk in some studies,^23,24 and with a lower risk of ischemic stroke in others.²⁵

Consuming less sodium and more potassium. In addition to decreasing the risk for hypertension, lower sodium intake has been found to decrease stroke incidence and mortality.^26,27 When compared with persons consuming the lowest amounts of potassium, those eating the highest amounts had the lowest stroke mortality.^28,29

Maintenance of healthy body weight. The risk for stroke increases with the degree of overweight,^30,31 although evidence to date is stronger for men than for women.^32,33 The same dietary changes that reduce cholesterol and blood pressure also tend to reduce body weight (See Hyperlipidemia and Hypertension).

Limiting alcohol consumption. High alcohol intake (30–60 grams, or 3–6 drinks, per day) is associated with a greater risk of stroke.^34,35 Consuming moderate amounts of alcohol (1–2 drinks per day) appears to reduce stroke risk,^34,36 but may aggravate risk for other conditions, such as breast cancer.

After stroke occurs, adequate nutrition is an essential part of clinical care. In the FOOD Trial Collaboration, poor nutritional status was associated with worse outcomes at 6 months post stroke.³⁷

Homocysteine. Elevated homocysteine levels are associated with heightened stroke risk. Because dietary supplementation with folic acid, pyridoxine, and vitamin B₁₂ reduces homocysteine levels, two large supplementation trials were carried out with these vitamins. Despite the strong theoretical basis, there was no observable decrease in stroke risk (Toole 2004, Lonn 2006).

Antioxidants. Antioxidant concentrations are often low in patients with ischemic stroke, and low intake of foods rich in antioxidants is associated with elevated stroke risk. However, so far, supplementation has not been shown to significantly reduce risk.

Orders

See Basic Diet Orders.

Sodium intake less than 2 grams daily.

Nutrition consultation to instruct patient in dietary recommendations and arrange outpatient follow–up.

Physical/occupational therapy consultation for home safety evaluation.

Stroke rehabilitation and speech therapy as appropriate.

What to Tell the Family  

Stroke occurs more frequently among those of advanced age, or who have blood vessel disease, family or previous history of stroke, and poor blood pressure control. However, persons who eat diets rich in fruits, vegetables, and fiber and low in saturated fat, cholesterol, and sodium decrease their risk for stroke, as do those who quit smoking, drink alcohol minimally, and engage in regular physical activity. It is important for the patient and family to follow a similar, healthful diet in order to decrease the risk of future stroke. In addition, family members should be aware of the warning signs of stroke, and immediately call 911 if these signs occur. Timing of care is critical to treatment success.