WASHINGTON — A high-quality carbohydrate diet is associated with reduced levels of C-reactive protein, Emily B. Levitan reported at conference on cardiovascular disease epidemiology and prevention sponsored by the American Heart Association.
The finding, from the Women's Health Study, suggests that diets characterized by a high intake of soluble fiber and a low glycemic index appear to reduce inflammation, and therefore might reduce the risk of cardiovascular disease and type 2 diabetes. Previous smaller studies have linked dietary carbohydrates with inflammation, as measured by a high-sensitivity C-reactive protein (hsCRP) level, said Ms. Levitan, a medical student at Harvard Medical School, Boston.
The first large, cross-sectional study examining both fiber intake and dietary glycemic burden involved 15,033 of the Women's Health Study participants who filled out food frequency questionnaires, provided a baseline blood sample, and were not users of postmenopausal hormones. They were divided into quintiles for each of five measurements of carbohydrate quality: glycemic index (the degree to which an average gram of carbohydrate increases blood glucose, compared with white bread); glycemic load (a measure of both glycemic index and carbohydrate quantity); total fiber consumed; insoluble fiber intake; and soluble fiber intake.
After adjustment for age, body mass index, smoking, and various other medical and dietary factors, geometric mean plasma concentration of hsCRP was significantly associated with dietary glycemic index. Soluble fiber intake was inversely related to hsCRP.
There was no linear relationship between hsCRP level and either dietary glycemic load or insoluble fiber intake. The relationship with total fiber consumed was also significant, largely because of the influence of soluble fiber, she said.