THE QUESTION Fiber, best-known for aiding digestion, can also help keep weight, cholesterol and blood sugar levels in check. Might this mean lower risk for stroke?
THIS STUDY analyzed data from eight studies, involving 327,537 adults who were generally healthy at the start of their study. During the study periods, which ranged from eight to 19 years, 11,236 participants had a stroke for the first time. People whose diets included the most fiber were less likely to have had a stroke than those who consumed the least. Stroke risk fell by 7 percent for every seven-gram increase in fiber intake daily. (Seven grams is equal to the amount of fiber in a serving of whole-grain pasta and two servings of fruit and vegetables.)
WHO MAY BE AFFECTED? Adults, whose odds of having a stroke — which occurs when blood flow to the brain stops, either because of a clot or a broken blood vessel — vary by age and race. Strokes can occur at any age, but they become more likely as you age, and risk is higher for blacks and Hispanics than for whites in the United States. High blood pressure, high cholesterol and smoking are primary risk factors for stroke, but diet is known to have an influence as well. Dietary fiber is the component of plant-based foods — fruit, vegetables and grains — that cannot be digested. Recommendations call for consuming 20 to 35 grams of dietary fiber daily from adolescence on, but most U.S. residents take in half that amount or less.
CAVEATS The analysis did not reveal whether benefit varied by type of fiber (soluble or insoluble) or by its food source. The studies took into account various stroke-risk factors, but other lifestyle factors may have affected the findings.
FIND THIS STUDY March 28 online issue of Stroke.
The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.