Issues in Assessing Whole Grain Intake. Katherine L. Tucker, Ph.D. Professor and Chair Department of Health Sciences Northeastern University

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1 Issues in Assessing Whole Grain Intake Katherine L. Tucker, Ph.D. Professor and Chair Department of Health Sciences Northeastern University

2 Most databases do not have whole grains well defined Challenge: to create a database that allows accurate assessment of whole grain intake by individuals

3 Definition of whole grains is not uniform The U.S. Food and Drug Administration definition of whole grains: cereal grains that consist of the intact, ground, cracked or flaked fruit of the grains whose starchy endosperm, germ and bran are in the same proportions as the intact grain requires foods that bear the whole-grain health claim to: (1) contain 51 percent or more whole-grain ingredients by weight per reference amount and (2) be low in fat. In the USDA Pyramid Servings Database, added bran and germ are counted toward servings of whole grains. We elected to count the contributions from added bran and germ toward whole grain consumption. Thus, the values for whole grain intakes in our database may be somewhat inflated according to the definition of the FDA.

4 Food Group Whole grains Refined grains Food Groups used for analysis Food items Amaranth, barley (pearled or flour), buckwheat (whole, groats, or flour), quinoa, bulgur, corn flour or corn meal (whole grain), kasha, wheat germ, processed bran (corn, oat, or wheat), phyllium seed, oats/oatbran, brown rice, wild rice, rice flour, rye and rye flour, triticale flour (whole grain), wheat (all hard/soft, spring/winter), whole wheat, popcorn, corn chips or corn tortillas (made with whole corn), oatmeal (instant or prepared), granola, oatmeal cookies, oatmeal bread, whole wheat pastas, whole grain breads (whole wheat, rye bread, other multi- and whole grain breads (including light), whole wheat cracker, whole whet pancakes, waffles, or bagels, mixed dishes made with whole grains, all cold breakfast cereals (fortified and non-fortified), made with whole grains, as well as bran (>=25% by weight), White bread (including light), roll, stuffing, cracker, biscuit, bagel, pancake, waffle, white flour, corn meal (refined), corn bread (made with refined), hush puppies, grits, corn chips, tortillas (made with white or refined corn flour), salty snacks, couscous, cracked wheat bread, croutons, cream of wheat or rice, couscous, all sweet baked goods (made with white flour), white rice, steamed or fried, mixed dishes with white rice, rice and beans, pasta with vegetables, macaroni and cheese, mixed pasta dishes made with refined grains, refined grain cereals (<25% by weight)

5 Procedures Goal of building the WG database was to estimate grain intakes in gram weights per day, in addition to servings per day. This process involved several steps, due to changes in the nutrient database over time (e.g., foods vs. ingredients) Challenges in quantifying how many grams of whole grains are contained in a given serving of grain food.

6 Procedures All grains, either whole or refined, were assigned a pyramid code from the USDA Pyramid Servings Database: A reference database of foods as servings per 100 g within 30 food groups We used 3 grain groups (total grain, whole grain, and non-whole grain) to calculate both servings and gram weights of whole grain intakes.

7 Procedures Recipes or mixed dishes were merged to the CSFII recipe database to disaggregate into ingredients and to obtain gram weights. The grain components of the ingredients were first calculated on the basis of 100 g of the total recipe and then remerged with the Pyramid Servings Database to obtain grain servings. For example, in a cookie with 11 ingredients and 10 g of white flour per 100 g of cookie, the flour gram weight was extracted along with the cookie recipe number and merged to the Pyramid Servings Database to obtain 0.63 servings of grain

8 Challenges Some foods cannot be disaggregated to the ingredient level. In these cases, the standard reference gram amount of grains was determined by multiplying by the number representing the pyramid serving. Specifically, a grain serving of 1 slice of bread contains 16 g of grain, while a grain serving of ½ cup of cereal contains 28 g of grain.

9 Challenges Some foods were not found in the Pyramid Servings Database e.g., rice flour, rye flour, quinoa, and triticale In these cases, we matched foods to the best possible match in the Pyramid Servings Database on the basis of whole grain content. For example, rye flour was matched to the Pyramid Servings Database food code for whole-wheat flour.

10 Database Challenges: Corn The Pyramid Database does not distinguish between corn meal, which is often refined, and whole grain corn in some of their recipes. For corn flour or corn meal to be considered a whole grain, it must contain the pericarp (part of the bran). For example, baked tortillas can be made with refined corn meal (non-whole grain) or whole corn meal (whole grain). We therefore needed to check the ingredients on the nutrition labels and/or contact the food manufacturers.

11 Database Challenges: Corn As we were able to estimate precise quantities of grains at both the ingredient and food levels, we were surprised when our database indicated some foods as containing grain servings. Example: imitation mayonnaise contributes grain. This is mostly because many foods contain ingredients such as corn starch and other stabilizers or fillers, which are made from grains. Because our dietary data are from diet records, we were able to count these foods as contributing to grain consumption, despite their limited contribution.

12 Consumer Challenges Many consumers assume that whole grains are darker in color than refined grains. Whole grains cannot easily be identified based on color alone, as color additives are often used to change the color of the food. Most 100% whole grain breads will list whole or whole grain in the ingredients, and increasingly manufacturers are listing 100% whole grain directly on the food package.

13 Consumer Challenges Commonly used terms that identify refined grain foods: bleached flour unbleached flour wheat flour enriched flour semolina 100% pure durum semolina organic unbleached flour multi-grain (depending on the ingredients) pearled barley degermed corn meal Unfortunately, the use of these terms can be confusing to consumers

14 Nutrient composition of selected whole and refined grains / 100 g Wheat flour Cornmeal Rice, cooked Barley, raw White, enriched Whole wheat White- Wheat Refined Whole White, longgrain, enriched Brown, long-grain Pearled Hulled Energy, kcal Carbohydrate, g Fiber, g < Protein, g Magnesium, mg Potassium, mg Calcium, mg Folate, μg

15 Published papers: Uses and Publications Maras J, Newby PK, Bakun P, Ferrucci L, Tucker KL. Whole grain intake, definition and database development: The Baltimore Longitudinal Study of Aging. Journal of Food Composition and Analysis 2009;22: Newby PK, Maras J, Bakun P, Muller D, Ferucci L, Tucker KL. Whole grains, refined grains, and cereal fiber measured using 7-d diet records: associations with risk factors for chronic disease. American Journal of Clinical Nutrition 2007:86(6): Used whole grain intake in developing an American Heart Association diet score.

16 Use of the database in the Baltimore Longitudinal Study of Aging Mean intakes of whole grains, refined grains, and total grains, as well as frequency of intake for major whole grain food groups and whole grain content for each group, were calculated Men and Women Mean age 57.5 y

17 Whole grain per serving, examples Food group USDA Standard serving size Weight (g) Whole grain per standard serving (g) Reported serving size (g) BLSA (mean ±S.D.) Whole grain per actual serving (g) (mean ± S.D.) Brown rice 1/2 cup ± ± 15 Corn chips, snack type, whole corn Whole wheat bread, 100% Multi-grain bread 1 oz ± ± 39 1 slice ± ± 11 1 slice ± ± 6

18 Baltimore Longitutidinal Study (BLSA) Sample Characteristics of 1516 Men and Women Participating in the Baltimore Longitudinal Study on Aging at Time of First Visit Sample characteristics 1 Whole grain (g/day) Refined grain (g/day) Average Total Energy (kcal) Women (n=517) Men (n=999) 25.1 ± ± ± ± ± ± 539 On average, women consumed more whole grain per day than men Men consumed more refined grains per day than women Adapted from Maras et. al. J food comp & anal 2009.

19 Major food group contributors to whole grain intakes and % contribution to intakes of adults in the Baltimore Longitudinal Study of Aging, by decade Food group n = 130 n = 551 n = 446 n = 299 n = 146 % % % % % High fiber cold breakfast cereal High fiber hot breakfast cereal Corn chips, snack type Multi-grain bread Rye bread Popcorn Brown rice Whole wheat bread, 100% Total whole grain (mean ± SD, g) 13.8 ± ± ± ± ± Includes all cold breakfast cereals made with whole grains, as well as bran. 2 Includes oatmeal and other high fiber hot cereals. 3 Includes mixed grain breads made with whole grains (not 100% whole wheat).

20 Whole grain intake in relation to health measures in the BLSA N Q1 Q5 P trend BMI (kg/m2) * 25.5 ± ± Waist circumference (cm)* 87.4 ± ± Total cholesterol (mmol/l)** 5.71 ± ± h Glucose (mmol/l)*** 8.24 ± ± * Adjusted for age, age2, sex, total energy, decade of visit, race, education, vitamin supplement use, smoking, and percentage of energy from saturated fat, alcohol, and refined grains. **With additional adjustment for BMI, use of lipid-lowering medication, and hypercholesterolemia. *** With additional adjustment for BMI, use of oral hypoglycemic medication, and diabetes. WG were not significantly associated with blood pressure, triglycerides or insulin in adjusted models. Newby et al Am J Clin Nutr 2007;86:

21 Thank you! With acknowledgement of Janice Maras and Kirsten Newby for their contributions to the development of the database, statistical analyses and manuscripts Funding was from General Mills Bell Institute