Rebecca Mozaffarian of the Harvard School of Public Health in Boston said the health benefits of switching from refined to whole grain foods are well established, including lower risk of cardiovascular disease, weight gain, and type 2 diabetes.
Based on this evidence, the U.S. Department of Agriculture's 2010 Dietary Guidelines recommend Americans consume at least three servings of whole grain products daily. New U.S. national school lunch standards require that at least half of all grains be whole grain-rich.
There are several whole grain stamps and labels on foods with whole grains and other ingredients. For example, the Whole Grain Stamp identified grain products that were higher in both sugars and calories than products without the stamp, the study found.
Mozaffarian and colleagues examined nutrition label information on 545 products. The best indicator was the American Heart Association's ratio of no more than 10 parts carbohydrate to 1 part fiber.
However, it required some math:
"For example, a serving of cereal with 20 grams of carbohydrate and 5 grams of fiber -- 20 divided by 5 is 4, which is less than 10, so it's a healthy choice," Mozaffarian said.
The study was published in the journal Public Health Nutrition.