BOSTON – Three studies presented at the 2015 Experimental Biology annual meeting, held March 28 to April 1 in Boston, revealed how grains, including whole grains and refined grains, may fit in a healthy diet, providing nutrients in a cost-effective way.
The Grain Foods Foundation, Washington, supported the studies. Victor L. Fulgoni III, Ph.D., senior vice-president of Nutrition Impact, L.L.C., Battle Creek, Mich., and Yanni Papanikolaou, vice-president of Nutritional Strategies, Inc., Paris, Ont., led the studies.
“We are excited to be a part of the nutrition science community by supporting research that will help Americans better understand the grain foods they eat and feel good about their dietary choices,” said Christine Cochran, executive director of the Grain Foods Foundation.
The initial focus will be on publishing the studies, Dr. Fulgoni said.
“Our focus is going to be to get this into peer-reviewed literature, so it could be useful in any policy debates once it’s published,” he said.
One study compared 10 different grain food patterns with the ideal grain food composite in the Dietary Guidelines for Americans 2010, which is six daily servings of grain with half of the servings being whole grain. The study used data from “What We Eat in America 2010.” A modeling analysis was conducted within a 2,000-calorie ideal food pattern.
A daily grain food pattern featuring two servings of whole grain and four servings of refined grain fared well. The refined grain category included enriched grains but did not break out enriched grains separately.
“The takeaway from all this is that we’re not by any means recommending that consumers should not consume whole grains,” Mr. Papanikolaou said. “We’re just saying that refined grains can be a healthy part of the diet. It can include cakes, cookies and pies, and as long as you’re doing it in a moderate fashion, it can be part of a healthy diet.”
Relative to the ideal daily pattern (six grain servings, including three whole grain), the pattern featuring two servings of whole grain and four servings of refined grains had 429 micrograms dietary folate equivalent, or 68%, greater dietary folate intake; 11.5 grams, or 47%, greater dietary fiber intake; 2 grams, or 2.5%, less total fat intake; and 0.4 gram, or 1.7%, less saturated fat intake. The pattern featuring two servings of whole grain and four servings of refined grains also had 31 calories, or 1.5%, greater energy intake and 89 mg, or 5.1%, greater sodium intake.
A daily grain pattern with all six servings as whole grain also compared well to the ideal pattern. Consuming all grains as whole grain resulted in 102 calories, or 5%, less energy; 2.25 grams, or 2.8%, less total fat; 0.4 gram, or 1.7%, less saturated fat; and 1.6 grams, or 6.5%, more dietary fiber. Consuming all grains as whole grain also resulted in 301 micrograms dietary folate equivalent, or 47.8%, less folate; and 237 mg, or 13.7%, more sodium.
Compared to the ideal pattern, consuming all grains as refined grains resulted in 95 calories, or 4.8%, less energy; 1.6 grams, or 1.9%, less total fat; 0.2 gram, or 1%, less saturated fat; 4.2 grams, or 17.1%, less dietary fiber; 116 micrograms dietary folate equivalent, 26.3%, less folate; and 131 mg, or 7.5%, more sodium.
A second study focused on the associations between grain food patterns and diet quality and nutrient intake. Mr. Papanikolaou said the findings show how grain foods provide needed nutrients.
“If you go back to the recently released Dietary Guidelines Advisory Committee report, the report highlighted that there continues to be what they call short-fall nutrients in the U.S. population,” he said. “It is a series of 10 nutrients. If you look at those 10 shortfall nutrients, grains contribute at least half of those.”
Researchers in the study used data from “What We Eat in America 2005-2010” to identify eight grain foods patterns: crackers and salty snacks; yeast bread and rolls; cakes, cookies and pies; cereals; pasta, cooked cereals and rice; quick breads; mixed grains; and no grain foods.
People in the no grain food pattern did not have any grain foods among their top 10 most consumed foods. Also, some foods with a grain component, such as pizza or beans and rice, did not qualify as a grain food.
“We had to be able to characterize grain consumption in components that people can report,” Dr. Fulgoni said.
Consuming many of the grain foods patterns resulted in significantly less saturated fat intake and significantly increased dietary fiber intake when compared to the no grain pattern. When compared to people in the no grain food pattern, people in the yeast bread and rolls food pattern had significantly lower sugar intake. Adults in the pasta, cooked cereals and rice food pattern had significantly lower body weight relative to adults in the no grain food pattern.
There were no significant differences observed when comparing those in the no grain cluster to those in the other grain foods patterns for body mass index or fasting blood concentrations of glucose, insulin, total cholesterol, L.D.L. cholesterol and triglycerides.
The third study focused on how cost-effective grain foods are in adding nutrients. Researchers used data from NHANES 2003-2004 since they are the only data that the U.S. Department of Agriculture linked to food costs. The study involved 113 total food categories, including 22 grain categories. Six of the 22 grain categories were especially cost-effective in providing energy and nutrients to the American diet.
The rolls/buns category and the rice category each ranked in the top five among the 113 total food categories for such nutrients/substances as dietary fiber, protein, folate, iron, magnesium, calcium, niacin and thiamin. Ready-to-eat cereals, the pasta/noodles/cooked grains category and the tortilla category also placed in the top five for certain nutrients/substances.Popcorn placed in the top five for dietary fiber and lutein/zeaxanthin. Grits/other cooked cereals placed in the top five for iron, and oatmeal placed in the top five for magnesium.