What are the differences between the layers of the food Pyramid

The USDA Food Guide Pyramid and MyPyramid

The Food Guide Pyramid was a recognizable nutrition tool that was introduced by the USDA in 1992. It was shaped like a pyramid to suggest that a person should eat more foods from the bottom of the pyramid and fewer foods and beverages from the top of the pyramid.

The Food Guide Pyramid displayed proportionality and variety in each of five groups of foods and beverages, which ascended in horizontal layers starting from the base and moving upward toward the tip: breads, cereals, pasta and rice; fruits and vegetables; dairy products; eggs, fish, legumes, meat and poultry; plus alcohol, fats and sugars. The 1992 USDA Food Guide Pyramid is shown in Figure 1-1.

In 2005, the USDA introduced MyPyramid, an updated version of the Food Guide Pyramid. Food groups were depicted in ascending vertical bands that emphasized the right proportions of food groups. An image of a person walking up a flight of stairs flanked the pyramid to emphasize activity. Instead of servings, quantities were measured in cups and ounces. The 2005 USDA Food Guide Pyramid is shown in Figure 1-2.

Other food guide pyramids followed, including the Mediterranean and Asian. Each of the ethnic food guide pyramids added, deleted, or substituted culturally correct foods with those in the USDA Food Guide Pyramid. For example, yogurt and goat milk products appeared in the Mediterranean Food Guide Pyramid, since intolerance to dairy products from cows is prevalent in this region of the world. Likewise, the Asian Food Guide Pyramid included soy products to replace the nutrients that are normally found in dairy products.

Additional food guide pyramids have been developed for children, seniors, vegetarians and a number of other groups to meet their specific nutritional needs. Yet, in 2011, after six years, the USDA replaced the Food Guide Pyramid with the nutrition guide MyPlate. Food guide pyramids are still used in other parts of the world and by some specialty groups.

Morsel

“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.”

—Hippocrates (Greek physician, 460 –c. 370 BC)

B. The Food Guide Pyramid

The Food Guide Pyramid was released by the USDA in 1992 [7], and has been widely distributed to both health professionals and consumers. Its appeal is twofold: It is a simple and actionable graphic, and it is based on detailed analyses that demonstrate its scientific accuracy. Both the form and the content of the Food Guide Pyramid underwent extensive testing. Numerous focus groups were conducted to ensure that consumers understood the messages being conveyed, and that the pyramid was a meaningful graphic for offering dietary guidance [45]. In addition, extensive analyses were conducted to determine what guidance would ensure adequacy (provision of recommended levels of nutrients) and moderation (low-fat, low-energy choices from each of the groups) [45]. Finally, typical dietary patterns in the United States were considered, which led to the selection of the food groups, and the number of servings of each, that would provide the recommended levels of nutrients at three daily energy levels (1600, 2200, and 2800 kcal/day) as shown in Fig. 2. Because the food groups are broadly defined, they can be adapted to meet specific cultural and personal preferences. Thus, the Food Guide Pyramid combines the dietary guidelines and the RDAs/DRIs into a single tool that is both scientifically based and consumer friendly.

Serving sizes for the foods in each Food Guide Pyramid food group, except the tip, are specified [7] as shown in Fig. 3. Serving sizes are smaller than many typical portions. For example, a slice of bread or one-half cup of pasta is a serving of the grains group, although typical portions are substantially larger than these. (Adults typically consume about two slices of bread per eating occasion, and about one cup of pasta [46].)

Many variations of the Food Guide Pyramid have been proposed, but most are specific interpretations of the pyramid's more general guidance. For example, a children's pyramid was released by the USDA in 1999 that offers a graphic that includes foods frequently consumed by children [47] (see Fig. 4). It is also a departure from the original (adult) Food Guide Pyramid, in that the importance of physical activity is emphasized with pictures of children engaged in several types of physical activity shown around the pyramid graphic. Although pyramids for various cultural or ethnic groups have been proposed, there is seldom the same level of analytic research for these variations as was conducted for the original, more general, Food Guide Pyramid. Health professionals should be cautious about recommending food guides that have not undergone the rigorous testing of the Food Guide Pyramid.

The Food Guide Pyramid is based on the 1989 RDAs and on the 1990 dietary guidelines. As explained in Section II of this chapter, the 1989 RDAs are being substantially revised as part of the process of setting the new DRIs. In addition, the dietary guidelines have been modified and expanded twice (in 1995 and 2000) since the pyramid was developed. To date, the only change in either type of guidance that is likely to significantly affect the Food Guide Pyramid is the increased recommendation for calcium. As reflected in the Food Guide Pyramid that is included in the 2000 dietary guidelines [5], three (rather than two) servings of dairy products would be required for adults over the age of 50 in order to meet the new AI for calcium of 1200 mg/day. Three servings would also be recommended for children and young adults 9–18 years of age (rather than those 13–24 years of age). It is anticipated that the Food Guide Pyramid will be reevaluated when the process of setting the DRIs is complete.

The Asian Food Guide Pyramid

The Asian Food Guide Pyramid was created in 2000 by Oldways Preservation & Exchange Trust. It depicts foods and beverages that replicate the traditional Asian diet for good health and longevity. It is shaped like a pyramid to show the recommended proportions of foods and beverages—heavier consumption at the bottom of the pyramid and lighter consumption at the peak.

While the USDA replaced MyPyramid with MyPlate in 2010, the Asian Food Guide Pyramid still reinforces the choices that are the foundation of a healthy Asian diet. The Asian Food Guide Pyramid is shown in Figure 12-9.

The Asian food pyramid portrays a mostly plant-based low-fat Asian diet, with a strong foundation that is built on daily physical activity. Rice, rice products, noodles, breads, millet, corn and other whole grains comprise the next layer, topped by a substantial layer of fruits, legumes, nuts and seeds and a sizeable amount of vegetables. This layer is topped by a smaller layer of vegetable oils, followed by fairly equal layers of fish and shellfish, eggs and poultry, sweets and meat, with meat at the pinnacle of the pyramid.

Daily servings of grains, fruits, legumes, nuts, seeds, vegetables, and vegetable oils are recommended, with optional daily servings of dairy, fish and shellfish. Eggs, poultry and fish are recommended weekly, and meat is recommended monthly. Eight glasses of water or tea are recommended daily, and sake, wine and beer are recommended in moderation [28].

Vegetarian Food Guides

A vegetarian food guide pyramid developed by Loma Linda University includes recommended servings of relevant food groups based on energy needs for both vegans and LOV. USDA's MyPlate provides resources for vegetarians, including alternative protein sources, tips for vegetarians, and the Vegetarian Nutrition Resource List. Additionally, the General Conference of Seventh-Day Adventists established the vegetarian MyPlate, a vegetarian version of the USDA MyPyramid; a vegan MyPlate is also available from the Vegetarian Resource Group. A Japanese vegetarian food guide has also been created for both the general public and the health professionals to promote adequate intakes of all nutrients (Figure 1).

MyPyramid for Older Adults

Modifications made to the original version of the Food Guide Pyramid specifically for older adults include (1) narrowing the pyramid base to reflect diminished energy requirements; (2) inserting icons to represent illustrative examples of nutrient-dense food choices within each food grouping, such as deep-green leafy vegetables and fruits with intense orange-colored interiors; (3) illustrating forms of foods particularly useful when adapting to the changing needs and abilities of older adults, such as bags of frozen vegetables and fruits, low-lactose dairy products, and canned low-sodium vegetables and low-sugar fruits; and (4) including two extra bands at the foundation of the pyramid with icons of water glasses to emphasize the importance of adequate fluid intake, as well as icons of individuals engaging in exercise to emphasize the importance of regular physical activity (Figure 1; Lichtenstein et al., 2008). Regarding the food icons, not only is specific emphasis given to vegetables and fruits with deep-colored interiors that tend to be nutrient- dense, but also to (1) whole vegetables and fruits, rather than juice, to contribute to fiber intake; (2) whole grains and cereals products, rather than refined grain products, to contribute to fiber intake; (3) low-fat and nonfat dairy products as well as low-lactose dairy products, to minimize saturated fat intake and promote continued intake of calcium rich foods; (4) examples of protein-rich foods that are low in saturated fat and high in protein quality to ensure adequate intake; and (5) liquid vegetable oils and soft spreads that contribute critical unsaturated fat to the diet.

The Food Guidance System

The Dietary Guidelines for Americans and the Food Guidance System replaced the Food Guide Pyramid, which was first introduced in 1992.5,7 Key recommendations of the Dietary Guidelines are presented in an easy to use format that can be customized for the consumer. Depending on individual energy needs, specific quantities of foods from each food group are used to define potential optimal health. Furthermore, the current Food Guidance System includes physical activity assessment and recommendations for activity for the first time in the history of the Pyramid graphics.

The Center for Nutrition Policy and Promotion (CNPP), a branch of the USDA, is ultimately responsible for the promotion of the Dietary Guidelines for Americans. The “MyPyramid” (Figure 14-2), a tool designed to translate the Food Guidance System to a graphic and interactive representation, allows each person to monitor his or her food and physical activity to achieve optimum health. “MyPyramid” illustrates six recommendations including personalization, gradual improvement, physical activity, variety, moderation, and proportionality. The interactive technology afforded by the government website allows each consumer to enter his or her own age, gender, and physical activity for personal recommendations and to compare individual food intakes to the Dietary Guidelines for Americans.5

1990s: Coordination of Dietary Guidance Tools

During the 1990s, new nutrition education tools were developed and existing guidance was refined (Davis and Saltos, 1995). These included the USDA Food Guide Pyramid and the first Healthy Eating Index, the tool for evaluating adherence to some of the guidelines was also published during the 1990s (Kennedy et al., 1994).

Graphics or icons for healthy eating have been used for many years in this country and abroad. They have increasingly been incorporated into food guidance systems to provide a graphic representation of the basic concepts they embody: adequacy, balance, variety, moderation, and proportionality among others. The graphic was only one element of nutrition education, with a focus only on major messages rather than all of the subtleties of healthy eating. Nevertheless, it provided a pictorial representation of key points in a healthy eating pattern for those who want one.

During the early 1990s, nutrition scientists in the USDA crafted this visual graphic or icon to depict ideal consumption patterns that conformed to the 1990 DietaryGuidelines and met the most current RDAs. This followed earlier and somewhat less successful efforts that date to the early 1980s, which involved a “food wheel” that included the total diet concept and energy balance. The 1992 food guide graphic's food group categories were based on both the distribution of nutrients in various food groups and existing food consumption patterns. Extensive argument ensued about whether a bowl, a pyramid, or some other graphic was most appropriate to convey concepts of balance, variety, moderation, and proportionality, and which foods should be placed in each food group—an argument that continues until today. Market research was done to examine the various shapes and settle the argument. The Pyramid was adopted as the best graphic for conveying these concepts on the advice of the expert consultants, and in 1992, the USDA Food Group Pyramid was released (Kennedy, 1994). It quickly became popular. Similar pyramids and other graphics followed in the United States and abroad (Dwyer et al., 2002).

Age-specific pyramid icons developed in the later 1990s, and the USDA issued a child pyramid on dietary guidance for children younger than 5 years, who have different needs than older individuals. The Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University produced a Tufts “Elder Pyramid” for individuals older than 70 years because elders’ needs are slightly different than younger adults for vitamins B 12, D, calcium, nutrient dense foods, calories, and water. These pyramids involved very few changes from the 1992 Pyramid and were also likely to provide a diet that was adequate in nutrients.

During the 1990s, many other nongovernmentally based pyramids proliferated, including those for various ethnic eating patterns such as the Mediterranean Diet, the Asian Diet, special eating patterns (e.g., vegetarian), and for special age-groups. They varied in their nutrient adequacy; some were carefully tested to make sure that they made nutrient targets, while others were not.

1. MEAL PLANNING TOOLS

Several formats for nutrition education tools have been applied in multiple areas of clinical nutrition. These include guidelines, menu approaches, counting methods, and exchange systems.

Guidelines, such as the Food Guide Pyramid, are a tool to provide basic information to help people make healthy food choices. They may include some information on servings and food preparation but not the specificity of nutrient information that can be found with other methods. Guidelines work well as a tool for initial education if precision in nutrient intake is not required. They may contain sufficient information for some people to be able to make eating behavior changes that reduce health risks and improve clinical indicators.

Menus are a tool to give clients specific direction on what to eat, including food type, preparation method, and serving size. For survival education, several days of menus can be written using familiar foods that ensure appropriate nutrition. The number of patients who carefully collect their tray menus during a hospital stay attests to the popularity of this approach. Menu planning tools generally rely on input from the patient so that food likes and dislikes can be taken into consideration. Menu planning can be combined with other instructional formats and used at the practical and ongoing education levels as well. Computer programs are becoming available that plan menus taking into account the nutrient prescription and individual food preferences.

Counting methods have become popular in recent years although one tool, The Point System, was introduced as early as 1944 [29]. Calorie counting is a standard approach for weight management. Fat gram counting is utilized in teaching materials for cholesterol reduction, cancer prevention, and weight management. Carbohydrate counting, initially considered a technique for intensive insulin therapy, is now being used with all types of diabetes for initial as well as continuing education.

Exchange approaches focus on food groups versus individual foods to teach nutrition principles. A popular example is the Exchange Lists for Meal Planning [30] that has been used for decades to instruct patients with diabetes. The system provides a tool for teaching patients how to select a diet that meets a macronutrient prescription. The exchange lists concept has been adapted for weight management education and is sometimes applied to nutrient information provided with recipes and manufactured food products. The Plate Model, a common teaching tool in Europe, has been used in the Diabetes Atherosclerosis Intervention Study (DIAS) [31]. The method uses a visual tool of a plate divided into three sections: one covers one-half of the plate and the other two are one-quarter sections. The guidelines place vegetables including salads in the one-half plate section, grains in one of the one-quarter sections and meat and alternatives in the other one-quarter section. Other food groups are included as side dish servings. DIAS has established target nutrient intakes for study participants that are evaluated by annual 24-hour recalls. Both the Plate Model and the more quantitative exchange lists have been used to help DIAS participants achieve the study goals.

Adaptations of the above tools for nutrition education can be found to match many idiosyncratic learner characteristics. Simplified versions appropriate for initial education or for low-literacy clients and versions that have been translated into Spanish are the most common tools. A recent trend in nutrition education materials is to provide “copy masters” for client education tools that can be photocopied without copyright infringement. Purchasing reproducible tools offers nutrition counselors an efficient way to have a wide range of teaching materials available to meet individual client needs. Even more promising is the emerging option of computer software providing nutrition education tools. Computer programs allow the provider to tailor materials to patient characteristics and to change content if it becomes obsolete.

MYPYRAMID FOOD GUIDANCE SYSTEM

The MyPyramid Food Guidance System is a pictorial representation of the USDA's Daily Food and Physical Activity recommendations. Released in 2005, MyPyramid replaced the nation's previously well-known nutrition education tool, the Food Guide Pyramid (1992). In MyPyramid, daily physical activity is represented by the stairs on the left side of the pyramid. Food groups are represented by the vertical bands, which comprise the body of the pyramid. Bandwidth indicates portion size; the wider the band, the more foods from that group should be consumed. Examples of portions, or serving sizes, are further delineated for each food group. However, in most cases, the serving sizes used in MyPyramid are considerably smaller than the exaggerated portion sizes that many Americans have become accustomed to. In MyPyramid, foods are organized into five major groups and one miscellaneous category. The latter category includes fats, oils, and sweets, all of which should be consumed sparingly. An individualized nutrition plan based on personal factors such as age, gender, and physical activity, can be developed using the online tools, such as the MyPyramid Menu Planner and the MyPyramid Tracker (http://www.MyPyramid.gov). This website, which contains a host of useful nutrition information for the public and health professionals, also offers a number of food guidance pyramids for special populations, such as pregnant women, vegetarians, and children. The child-friendly version of MyPyramid, called MyPyramid for Kids, is designed to educate children ages 6 to 11 years old about nutrition and to assist them in making appropriate dietary choices (Fig. 12-1).

Meat Consumption and Cholesterol

Tande et al. (2004) used data from 9111 men and women ages 20–59 years who participated in the National Health and Nutrition Examination Survey III (NHANES III) to examine the associations between the five major food groups as delineated by the food guide pyramid and serum lipid levels. In linear regression analyses adjusted for age, sex, body mass index (BMI), waist to hip ratio, education, income, smoking, ethnicity, activity, and menopausal status, higher meat intake was associated with higher LDL-cholesterol (p = 0.02). In the Oxford Vegetarian Study on about 6000 vegetarians and 5000 nonvegetarians from the UK, mean total cholesterol and LDL-cholesterol concentrations (adjusted for age and sex) were significantly lower in vegans than in meat eaters, with similar intermediate levels among persons who ate fish but not meat or those who were lacto-ovovegetarians. Mean HDL-cholesterol levels were highest among fish eaters with similar levels among the other groups (Thorogood et al., 1987). These differences in plasma lipid concentrations persisted with further adjustment for BMI (Thorogood et al., 1989). In stepwise multiple linear regression analyses, after adjusting for age, meat consumption was positively associated with mean total cholesterol levels in both men and women (Appleby et al., 1995). Among 518 men ages 70–89 from the Zutphen Study, dietary intake was assessed by the cross-check dietary history method and participants were aggregated by cluster analysis into four groups, including one group characterized by high meat consumption (which also had higher intake of eggs, cheese, and edible fats), and another group by a healthy dietary pattern. Mean total serum cholesterol was 0.26 mmol L−1 higher in the high meat cluster compared with the healthy diet cluster (Huijbregts et al., 1995). Cross-sectional data from the Coronary Artery Risk Development in Young Adults (CARDIA) study showed that individuals who ate red meat and poultry less than once a week (n = 47; approximately 1% of CARDIA cohort) had lower mean levels of total plasma cholesterol (p = 0.001), LDL-cholesterol (p = 0.001), and triglycerides (p = 0.015) than those who ate meat more frequently (Slattery et al., 1991).

In a small controlled trial, Sacks et al. (1981) examined the effect of meat intake (250 g of beef/day) for 4 weeks among 21 strict vegetarians, showing a significant increase in plasma total cholesterol by 19% at the end of the 4-week period. No changes in plasma HDL-cholesterol were observed. A more recent randomized clinical trial comparing the effects of lean red meat and lean white meat consumption on serum lipid levels of 191 men and women with hypercholesterolemia demonstrated reductions in LDL-cholesterol (by 1–3%) and elevations in HDL-cholesterol (by about 2%) in both groups in 36 weeks of treatment (Davidson et al., 1999).