Most likely you’ve heard someone say, “I’ve cut all refined and processed foods, including white bread, from my diet.” Considering the definition of refined means “free from impurities, fastidious, or cultivated,” it’s curious that refined grains have taken on a negative connotation. What if removing refined grains was not necessary for good health and could contribute to having fewer healthful nutrients in your diet?
Dr. Glenn Gaesser, Professor of Exercise Science and Health Promotion and Director of the Healthy Lifestyles Research Center, Arizona State University, wanted to find out why refined grains are viewed as unhealthy by so many people, including recommendations from the 2015 Dietary Guidelines for Americans Committee (DGAC). In a recent paper, Professor Gaesser uncovered several noteworthy facts and posed several questions:
- Recommendations to increase whole grain intake to reduce risk of many chronic diseases, including obesity, is clear. “There is rock solid evidence for the benefits of eating whole grains,” says Dr. Gaesser, yet only 2% to 7% of Americans meet the recommendation to consume at least one-half of grains from whole grains.
- While the DGAC recommends consuming half of grains from whole grains and reducing the intake of refined grains, the committee only reviewed evidence that looked at dietary patterns, not refined grains specifically.
- An “unhealthy dietary pattern” as defined in the research studies evaluated by the DGAC included red and processed meat, sugar-laden foods and drinks, French fries, full-fat dairy foods, and refined grains. What if refined grains are guilty by association with the other foods in this unhealthful dietary pattern?
- Refined grains include not only staple foods, like bread, rice, cereal, and pasta, but also cookies, cakes, doughnuts, brownies, muffins, sweet rolls, and even pizza! Are all refined grains created equal when it comes to health effects?
Untangling the evidence
Looking at multiple studies, called meta-analyses, that included 32 publications with 24 distinct groups of people, refined grain intake was not linked to an increase risk of heart disease, high blood pressure, stroke, type 2 diabetes, cancer, or obesity. In fact, one meta-analysis reported that higher consumption of refined grain was associated with a 5% lowerrisk of death from any cause. But you wouldn’t know that from the headlines blaming refined grains on all the world’s ills.
The “eat-only-whole-grains” message has become predominant in nutrition reporting. It is typical to pit foods against each other, to crown one food as good and healthful and another food as bad and unhealthy. However, the evidence to support that dichotomy for whole and refined grains doesn’t hold up upon further scrutiny. Dr. Gaesser’s investigation found that eating up to six or seven serving of refined grains does not increase the risk for many of the chronic disease affecting Americans.
An unintended consequence
While refined grains have been demonized, it is useful to remember that refined grains contribute more than just energy (calories) to our diets. Refined grains are enriched or fortified (see sidebar for definitions) with B-vitamins and iron. Eating refined grains can alleviate shortfalls of thiamin, riboflavin, niacin, and iron. Folic acid, a B-vitamin needed for healthy nerve and spinal cord development for babies, is found in refined grains and these grains are the largest contributor of folic acid in the diet. Refined grains also contribute dietary fiber, a nutrient sorely lacking in the diets of most Americans. “Grain foods contribute about 55% of all fiber in the American diet and about 40% of fiber intake comes from refined grains,” says Professor Gaesser.
Putting it all together
What does this research mean for you? First, it is helpful to realize that you should know your stuff before you cut. There is no reason to cut refined grains from your diet. Enjoying up to seven servings a day will contribute to nutrient intakes of several vitamins and minerals, and dietary fiber, and will not up your risk of disease.
It is also useful to think about refined grains in two distinct categories:
- Staple grains, such as bread, rolls, rice, and pasta
- Indulgent grains, such as cakes, cookies, pies, doughnuts, and other sweet desserts
Eat more grains from the staple category and less from the indulgent group. The sweet, indulgent group of grain foods contain higher levels of fat and sugar than the staple grains.
Continue to include whole grains in your diet, but there is no need to eliminate the refined grains.
DEFINITIONS
Whole grains: A grain containing all three parts of the grain: the bran, germ, and the endosperm. Whole grains contain fiber, antioxidants, the mineral magnesium, B vitamins, and plant compounds called phytonutrients that have many healthful properties.
Enriched grains: Enrichment is the process of replacing nutrients that were removed when the whole grain was processed. Enriched grains have B-vitamins niacin, riboflavin, and thiamin, and the mineral iron added back to the grain at levels similar to the original whole grain. About 95% of white flour is enriched; therefore breads, pastas, cereals, rolls, tortillas, and pretzels made from white flour are enriched with nutrients.
Fortified grains: Fortification is the addition of nutrients to a food where they are not naturally occurring. Milk is fortified with vitamin D to help the naturally occurring calcium be better absorbed. Grains are fortified with the B-vitamin folic acid at two to three times the levels found in the whole grain to help reduce birth defects.
Refinedgrains: Grains that have been processed to remove the bran. In the U.S. the terms refined, enriched, and fortified grains are used interchangeably.