The 2020 Dietary Guidelines Advisory Committee has completed their review of the evidence on nutrition and health. The final report reflects the Advisory Committee’s full examination of the evidence using three rigorous approaches: data analysis, systematic reviews, and food pattern modeling. The Scientific Report also includes advice to the United States Departments of Agriculture and Health and Human Services to consider in the development of the next edition of the Dietary Guidelines for Americans. The Advisory Committee’s Scientific Report is not a “draft” of the next edition of the Dietary Guidelines for Americans. USDA and HHS will consider the Advisory Committee’s Scientific Report, along with public and agency comments, as the Departments develop the 2020-2025 Dietary Guidelines for Americans.
The Vegetarian Resource Group submitted the following comment on the Advisory Committee report
To the U.S. Department of Agriculture and U.S. Department of Health and Human Services.
August 7, 2020
Thank you for the opportunity to submit comments on the Scientific Report of the 2020 Dietary Guidelines Advisory Committee.
We commend the Committee for their diligence, especially during this challenging time. We appreciate the inclusion of additional life stages in this report and support the overall overarching guidelines (pages 43-45/835).
Since the Committee has made dietary patterns a centerpiece of their report (according to page 14/835), we have chosen to focus our comments on the Healthy Vegetarian Pattern.
While we strongly support the inclusion of a Healthy Vegetarian Pattern as a healthy eating pattern for Americans, we have concerns with the composition of the dietary pattern. The food choices in the Healthy Vegetarian Pattern were informed by a survey (page 752/835) that is more than 10 years old and that was based on a single day’s dietary recall of self-described “vegetarians.” A large portion of the self-identified “vegetarians” consumed meat, fish, or poultry1 which prevents their diet intake records from being informative about the composition of a vegetarian diet which does not include meat, fish, seafood, or poultry.
The aforementioned study reported that 2.1% of the U.S. population identified themselves as “vegetarian” and that 3% of the vegetarians did not use any animal products on the day of the survey.1 In contrast, our most recent polls indicate that between 3.3% and 6% of the adult and child/adolescent U.S. population “never eats meat, fish, seafood, or poultry” and thus would be classified as vegetarian.2-5 Approximately half of these adult vegetarians and a quarter of the child/adolescent vegetarians “never eat meat, fish, seafood, poultry, dairy products, or eggs” and thus would be classified as vegan.2-5 Table 1 provides details about the percentages of vegetarians and vegans in our most recent surveys.
We recommend that additional research be conducted on the food choices of vegetarians (those who do not eat meat, fish, and poultry) including vegans (no meat, fish, poultry, dairy products, eggs) in the United States and that these results be used to inform the food choices in the Healthy Vegetarian Pattern. Additional support for the inclusion of food patterns for those using a vegan diet is found in Table 2 which presents the results of surveys of U.S. adults’ behavior when eating out. Many adults eat vegetarian, including vegan meals when they eat out. In our most recent survey, 46% of U.S. adults who ate vegetarian meals when eating out chose to eat vegan meals.2 In view of the consistent results of our polls demonstrating that as many as half of vegetarians do not eat dairy products or eggs and that those Americans sometimes choosing to eat vegetarian meals frequently choose to eat vegan meals, we urge the Committee to increase the flexibility of the Healthy Vegetarian Pattern to include vegan diets. An additional consideration is the potential health benefits of vegan diets.
Vegan diets are associated with health benefits, in some cases superior to those of lacto-ovo vegetarian diets and in some cases similar to those of lacto-ovo vegetarian diets. Specifically,
- A 15% lower incidence of cancer in vegans and an 8% lower incidence of cancer in vegetarians overall compared to nonvegetarians.6
- Vegetarians have a lower mean BMI than nonvegetarians (Vegetarians: -1.48 kg/m2; vegans: -1.72 kg/m2).6
- Vegetarians had a 27% lower risk of developing diabetes than did nonvegetarians. This reduced risk was seen in vegans and in lacto-ovo, lacto, and ovo vegetarians.7
- Vegetarians have lower total cholesterol (Vegetarian: -28.16 mg/dL; vegans: -31.02 mg/dL) and LDL cholesterol (Vegetarians: -21.27 mg/dL; Vegans: -22.87 mg/dL) than nonvegetarians.6
- Vegetarian diets, especially vegan diets, effectively promote weight reduction.8
- Changing from a nonvegetarian to a vegetarian or vegan diet is associated with a mean decrease in blood cholesterol concentration of 14 mg/dL and a mean decrease in LDL concentration of 13 mg/dL. Reductions of this scale correspond to an estimated 9 to 10.6% decrease in risk of heart disease.9
The current Healthy Vegetarian Pattern does not include options for those who do not eat eggs. There are many reasons that consumers choose not to eat eggs including taste preference, allergies, religious or cultural practices, and other considerations. In order to provide realistic guidance, options should be provided so that eggs do not appear as an essential component of the Healthy Vegetarian Pattern. This inclusion of the egg subgroup seems contrary to the Committee’s statement that “… a strength of the Food Patterns is that it has a tremendous amount of flexibility that allows it to be tailored to an individual’s cultural and taste preferences. This flexibility occurs because the resulting Patterns are only prescriptive for the larger food groups and subgroups amounts but not the specific types of foods to be consumed, permitting choices and options for the consumer.” (page 732/835). Eggs are a specific type of food and alternatives are not presented which would allow the flexibility of other subgroups. We strongly recommend that eggs not be in a subgroup unless non-animal-based alternatives are included in this subgroup.
Similarly, guidance is needed about alternative sources of the nutrients provided by the dairy group for those who do not use dairy products. While fortified soy milk is included in the dairy group, many consumers will not use 3 cups of fortified soy milk daily. We encourage the Committee to offer other options including increased use of leafy green vegetables and calcium-fortified foods in addition to soy milk, such as other plant milks and orange juice, as sources of bioavailable calcium.
We note that a study of Seventh-day Adventists found that lacto-ovo vegetarians, pescatarians, and semi-vegetarians all consumed smaller amounts of dairy products and eggs than did nonvegetarians10 suggesting that alternatives to dairy products and eggs are needed in the Healthy Vegetarian Pattern for those consistently choosing a vegetarian diet and for those who sometimes choose vegetarian or vegan meals. We recommend greater flexibility in the Healthy Vegetarian Pattern.
The Healthy Vegetarian Pattern has limited use of legumes, a food group with numerous health benefits including cholesterol-lowering, blood glucose control, and anti-inflammatory effects.11,12 Currently, on a 2000 calorie meal plan, only 1.5 cups (6 oz eq) of legumes/week are included as a protein food with an additional 1.5 c eq as vegetables (page 750/835). This is less than a half cup of beans daily. An older survey of self-defined U.S. vegetarians who did not eat meat on the day of the survey found that their average consumption of dried beans was about ½ cup daily.13 The inclusion of more legumes in the Protein Foods Group could allow greater flexibility, especially if the subgroups were eliminated and the foods in the Protein Foods Group (soy/nuts/seeds/legumes/eggs) could be chosen at will.
We note that in Table D14.3 (pages 750-751/835), that legumes in the Vegetable Group are measured in cup eq/wk whereas legumes in the Protein Foods Group are measured in oz eq/wk. We are concerned that the use of different units of measure (c eq and oz eq) depending on whether legumes are being counted as a protein or a vegetable will be confusing to consumers.
The Healthy Vegetarian Pattern for age 12-24 months only includes guidance for those toddlers not receiving human milk or infant formula. Although the Committee states that “most infants in the United States (66 percent) are no longer receiving human milk after age 12 months” (page 429/835), a third of the infants in the United States are receiving human milk after age 12 months and require guidance. Guidance is needed for toddlers who are receiving some human milk or infant formula and who are being fed according to the Healthy Vegetarian Pattern.
The Healthy Vegetarian Pattern for age 12-24 months does not include legumes in the Protein Foods Group and only a small amount of legumes are included in the Vegetable Group. Legumes can supply significant amounts of protein, iron, and zinc for toddlers.14 Inclusion of legumes in the Protein Foods Group adds additional flexibility and increases the likelihood that toddlers will become familiar with foods such as lentils and garbanzo beans that will eventually play a significant role in their diet.
The report states (page 467/835), “Without supplements and/or fortified products, it is not possible to meet all nutrient goals with a vegan diet at this age [12-24 months]. We agree that supplements and fortified foods are needed to ensure the adequacy of nutrients such as vitamin B12 and vitamin D. We question, however, why fortified foods were not used to develop a vegan food pattern for this age group. The Committee endorses the use of fortified dairy products to supply vitamin D and fortified infant cereals to supply iron and zinc, suggesting that fortified foods are acceptable. Given this acceptance of the used of fortified foods, it seems reasonable to provide guidance for the use of fortified foods and supplements by parents/caregivers who want to use a vegan diet for 12-24-month-olds.
In addition to the preceding comments that specifically address the Healthy Vegetarian Pattern, we have comments on other parts of the Report.
We encourage the Committee to
more broadly consider alternatives in all Patterns. For example, the Committee
notes that 88% of people do not meet recommendations for dairy foods (page
136/836). The Report also notes, “The dietary patterns commonly consumed by
racial-ethnic and cultural groups often have unique characteristics (such as
the lack of dairy intake by some groups) that differ from the Healthy
U.S.-Style Pattern. These differences may cause the patterns from these groups
to appear inadequate because some of the unique foods consumed in these
populations that provide the missing nutrients are not represented in the food
item clusters used in food pattern modeling. It is now, and will become even
more, imperative that dietary guidance reflect dietary patterns of growing
demographic groups, particularly LatinX and Asian populations “(page 800/835).
Use of alternatives, such as leafy green vegetables, tofu, fortified plant
milks in addition to soy milks, could allow the nutrition recommendations to be
more acceptable to a greater spectrum of the American population.
Another example of an area where more consideration of options should be included is the egg subgroup. All of the three Patterns include eggs as a subgroup. As discussed previously, this inclusion seems contradictory to the Committee’s statement that Patterns are not prescriptive for specific types of foods consumed. We notice that the Food Pattern Modeling Report15 includes an examination of the effect of increasing the number of eggs included in the Patterns but does not examine the effect of decreasing or eliminating eggs and replacing them with plant-based protein sources in all Patterns. Greater flexibility in food groups and subgroups seems needed in all Patterns to meet the needs of those with different cultural, religious, and other influences.
Although the Healthy Vegetarian Pattern includes legumes as a subgroup in the Protein Foods Group, the other Healthy Patterns fail to emphasize legumes as a protein source. Legumes have numerous health benefits.11, 12 Some of these benefits are illustrated in Table D8.1 (page 513/835). Legumes should be included in all food patterns as a protein source.
We note that Table D1.4 (page 185/835) should include some additional foods in the last column. Fortified plant milks and fortified orange juice supply vitamin D and are more readily available than mushrooms exposed to UV light. Fortified plant milks and dark green leafy vegetables supply bioavailable calcium. Seaweed is not typically recommended as an iodine source because their content is variable, and some sea vegetables provide large amounts of iodine.16
The Report repeatedly recommends seafood consumption in pregnancy due to the high DHA content of some seafood. Since DHA consumption is what underlies the potential benefits of seafood consumption, research that included DHA supplementation can be used to examine whether increased DHA consumption offers benefits. Benefits of DHA supplementation in pregnancy are primarily associated with gestational duration and birth weight. A meta-analysis of 70 randomized controlled trials (RCTs) found that omega-3 interventions in pregnancy consisting of either supplements (mainly DHA) or food were associated with a reduced risk of preterm birth (<37 weeks) and early preterm birth (<34 weeks), a slightly longer gestational length, and a reduced risk of having a low birthweight infant.17 Omega-3 supplementation in pregnancy was not associated with significantly improved cognition, IQ, vision, or other developmental or growth outcomes.16 Approximately 20% of people in the United States reported no fish or seafood consumption over a 30-day period.18 Guidance is needed throughout the Report for those who avoid fish due to allergies, cultural influences, preference, or because they are vegetarian or vegan. This is especially the case for pregnancy and lactation where this Report seemed to emphasize the consumption of fish.
The Report includes many excellent ideas for further research including expansion of diversity among populations studied and the expansion of USDA databases to incorporate additional foods and beverages from diverse populations” (pages 766-767/835). We encourage increased sampling of those choosing vegetarian, including vegan, dietary patterns and the expansion of the USDA databases to incorporate additional foods commonly eaten by vegetarians, including vegans, especially fortified foods and replacements for animal-derived products. Additional research should be conducted, which could be used to inform future vegetarian food patterns, on the food choices of vegetarians who do not consume meat, fish, seafood, or poultry and those vegetarians who also do not consume dairy products and eggs.
We noted the statement in the Committee’s letter to the Secretaries, “In addition, comments identified the importance of evaluating sustainability of recommended dietary patterns, addressing the social and economic aspects of access to foods that are components of healthy dietary patterns, and considering systemic changes to encourage behavior change consistent with the guidelines. These comments point to areas that are important for USDA and HHS to address through appropriate mechanisms, and their consideration may provide useful approaches for implementing the recommendations in the Dietary Guidelines for Americans” (page 3/835). We support these comments and strongly encourage USDA and HHS to address the issues of social and economic access to foods that are components of healthy dietary patterns and of including sustainability as an important consideration when recommending dietary patterns.
References
- Juan W, Yamini S, Britten P. Food intake patterns of self-identified vegetarians among the U.S. population, 2007-2010. Procedia Food Sci. 2015;4:86-93. doi:10.1016/j.profoo.2015.06.013.
- How Many Adults in the U.S. are Vegan? Vegetarian Resource Group. https://www.vrg.org/blog/2020/08/07/how-many-adults-in-the-u-s-are-vegan-how-many-adults-eat-vegetarian-when-eating-out-asks-the-vegetarian-resource-group-in-a-national-poll/ Published August 7, 2020.
- Stahler C. How Many People are Vegan? How Many Eat Vegan When Eating Out? Vegetarian Resource Group. https://www.vrg.org/nutshell/Polls/2019_adults_veg.htm Published 2019.
- How Many Adults in the U.S. are Vegetarian and Vegan? Vegetarian Resource Group. https://www.vrg.org/nutshell/Polls/2016_adults_veg.htm Published 2016.
- How Many Teens or Other Youth are Vegetarian or Vegan? Vegetarian Resource Group. https://www.vrg.org/blog/2014/05/30/how-many-teens-and-other-youth-are-vegetarian-and-vegan-the-vegetarian-resource-group-asks-in-a-2014-national-poll/ Published May 30, 2014.
- Dinu M, Abbate R, Gensini GF, Casini A, Sofi F. Vegetarian, vegan diets and multiple health outcomes: a systematic review with meta-analysis of observational studies. Crit Rev Food Sci Nutr. 2017;57:3640-3649.
- Lee Y, Park K. Adherence to a vegetarian diet and diabetes risk: a systematic review and meta-analysis of observational studies. Nutrients. 2017 Jun 14;9(6). pii: E603.
- Huang RY, Huang CC, Hu FB, Chavarro JE. Vegetarian diets and weight reduction: a meta-analysis of randomized controlled trials. J Gen Intern Med. 2016;31(1):109‐116.
- Wang F, Zheng J, Yang B, Jiang J, Fu Y, Li D. Effects of vegetarian diets on blood lipids: A systematic review and meta-analysis of randomized controlled trials. J Am Heart Assoc. 2015;4(10):e002408.
- Orlich MJ, Jaceldo-Siegl K, Sabaté J, Fan J, Singh PN, Fraser GE. Patterns of food consumption among vegetarians and non-vegetarians. Br J Nutr. 2014;112(10):1644-1653.
- Messina V. Nutritional and health benefits of dried beans. Am J Clin Nutr. 2014;100 Suppl 1:437S-42S.
- Pribis P. The role of legumes in maintaining health. In Craig W, ed. Vegetarian Nutrition and Wellness. Boca Raton, FL: CRC Press; 2018:1-9.
- Haddad EH, Tanzman JS. What do vegetarians in the United States eat? Am J Clin Nutr. 2003;78(3 Suppl):626S-632S. doi:10.1093/ajcn/78.3.626S
- Mangels R, Driggers J. The youngest vegetarians: Vegetarian infants and toddlers. ICAN: Infant, Child & Adolescent Nutrition. 2012; 4:8-20.
- 2020 Dietary Guidelines Advisory Committee and Food Pattern Modeling Team. Food Pattern Modeling: Ages 2 Years and Older. 2020 Dietary Guidelines Advisory Committee Project. Washington, D.C: U.S. Department of Agriculture. Published 2020.
- Teas J, Pino S, Critchley A, Braverman LE. Variability of iodine content in common commercially available edible seaweeds. Thyroid. 2004;14(10):836–841.
- Middleton P, Gomersall JC, Gould JF, Shepherd E, Olsen SF, Makrides M. Omega-3 fatty acid addition during pregnancy. Cochrane Database Syst Rev. 2018;11(11):CD003402. doi: 10.1002/14651858.CD003402.pub3
- Jahns L, Raatz SK, Johnson LK, Kranz S, Silverstein JT, Picklo MJ. Intake of seafood in the US varies by age, income, and education level but not by race-ethnicity. Nutrients. 2014;6(12):6060-6075. doi:10.3390/nu6126060