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Whole Grains and Health


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why this is an important challenge to meet.

      Accurate quantification of whole grains in food is of fundamental importance for research on whole grains and for regulatory and labeling policies, including for checking compliance with regulations around labeling and health claims based on whole grain content. Estimation of whole grain intake requires information about the whole grain content of available foods, yet many products contributing whole grains to the diet do not state the amount or proportion of whole grains present. Since whole grain content in foods can vary from very little to 100%, a large amount of guesswork may go into estimating whole grain content, potentially reducing the accuracy of associations between whole grains and health. Quantifying whole grains in foods is also important for clearly and honestly marketing whole grains to consumers, to ensure consumer confidence that a product labeled as containing whole grains does actually contain what is stated.

       5.2.1 How whole grain content of cereal products has been reported

      Whole grains are a diverse group of cereals and pseudocereals that are on one level well defined as ingredients, but at the level of food products, poorly defined due to no universally accepted definition of what constitutes a whole grain food product. This is further clouded by a wide range of definitions used by scientists, regulatory authorities, private labeling initiatives and what is reported “on pack” for food products containing cereals.

      In the scientific literature, the use of “whole grains” to identify foods of potential interest for reducing disease risk, first used a cut‐off point of 25% whole grains (as a percent of total weight as consumed) in a product.(3,4,5) Deciding on a threshold for whether a product would count as being “whole grain” or not was necessary to establish whether there was a relationship between foods containing whole grains and health. However, this also means that a food included as whole grain for the purposes of estimating intake could contain anywhere between 25% and 100% of its total weight as whole grains. A product that contained 26% whole grains would be considered to contribute the same amount of whole grains to overall whole grain intake as a food with 100% whole grain ingredients. Further, using this threshold does not account for products that contain <25% whole grains, so it would not be possible to determine whether such foods make an important contribution to whole grain intake. So while a 25% threshold was a good starting point, as research on whole grains has progressed since the early studies associating whole grain intake with reduced disease risk, it has been necessary to further develop how whole grain intake is estimated and how whole grain content in foods is measured and used to estimate intake.

       5.2.2 Quantifying whole grain content

      Much of what is known about whole grain content of food is based on what is reported on food packaging or in recipe books. Few countries have clear guidelines for labeling whole grain content, which limits the value of a product labeled as “whole grain” for estimating intake or for consumer communication. There are three main approaches to quantifying whole grain content in food:

       The percentage of the grain ingredients that are whole grain (i.e., whole grain vs. refined grain)

       The percentage of the product dry weight that is whole grain (i.e., without the influence of water added during food processing or cooking)

       The percentage of the product as consumed that is whole grain (i.e., accounting for non‐grain‐based ingredients)

      The United States Dietary Guidelines for Americans, in their practical advice for helping consumers select whole grain products, advise that selecting products with “whole grains as the first ingredient” is a good consumer shortcut for choosing foods that will provide a substantial proportion of whole grains. However, it still falls short as a quantitative tool, and from a regulatory and consumer perspective, requires knowledge about ingredient lists and close‐up investigation of the back of the packaging to make this crude measurement of whole grain content.

      Most cereal foods have water added, and depending on what is quantified, this may make a big difference to a whole grain label that is based on percentage of a product’s weight as consumed. For example, dried pasta contains essentially no water, and if made from only whole grain durum wheat, could be labeled as “100% whole grain pasta.” The same pasta cooked and frozen for a ready meal would be only 33% whole grain if reported on a fresh weight basis, although the amount of dry pasta in a serving would be the same. This highlights the need to account for water content when reporting whole grain content in foods.