Study links whole grains to fiber intake
MINNEAPOLIS — Whole grain foods make a substantial contribution to total dietary fiber intake and should be promoted to meet recommendations, according to a study published on-line Jan. 16 in Nutrition Research. Researchers from the University of Minnesota in St. Paul, Minn., the General Mills Bell Institute of Health and Nutrition in Minneapolis, and General Mills, Inc. in Mumbai, India, conducted the study.
The researchers used one-day food intake data from 9,042 people in the U.S. National Health and Nutrition Examination Survey 2009-10. They divided whole grain intake into three groups: no intake, low intake of less than 3 oz equivalent daily and high intake of 3 oz equivalent or higher daily. Results showed 2.9% of children ages 2 to 18 and 7.7% of adults consumed at least 3 whole grain oz equivalents daily. A high percentage of children (38.8%) and adults (41.9%) consumed no whole grains. Most children (58.3%) and adults (50.4%) had a low intake.
For children, those in the high whole grain intake group were 59 times more likely to fall in the third fiber tertile compared to those with no whole grain intake. For adults, those in the whole grain intake group were 76 times more likely to fall in the third fiber tertile.
Children who consumed at least 3 whole grain oz equivalents daily had total dietary fiber intake of 24.5 grams. Adults who consumed at least 3 whole grain oz equivalents daily had total dietary fiber intake of 28 grams a day.
For children in the high whole grain intake group, food categories contributing the most dietary fiber were grain mixtures/frozen plate meals/soups/meat substitutes (16.2%), ready-to-eat cereal (11%) and fruit (10.3%). For adults in the high whole grain intake group, the greatest contributors to dietary fiber were fruit (15.6%), vegetables (14.5%) yeast bread/rolls (11.9%) and R.-T.-E. cereal (10.7%).
Among people with the highest whole grain intake, whole grain R.-T.-E. cereal with no added bran, when compared to other R.-T.-E. cereal types, was the greatest contributor to total dietary fiber.
Whole grain sources for all children/adolescents included R.-T.-E cereal (25%), yeast bread/rolls (24%) and oatmeal (12%) and popcorn (12%). Top whole grain sources for all adults included yeast bread/rolls (27%), oatmeal (21%) and R.-T.-E. cereal (20%) and popcorn (9%).
Eating at least 3 whole grain oz equivalents daily helps ensure adequate consumption of total dietary fiber, the researchers said.
“Therefore, intake of W.G. foods, particularly W.G. R.-T.-E. cereals, oatmeal, yeast bread/rolls, should be encouraged to help Americans achieve both W.G. and total dietary fiber recommendations,” the researchers said.