Application of dairy-free vegetarian and vegan USDA food pattern models for non-pregnant, non-lactating healthy adults

Authors: Hess, Julie; Comeau, Madeline

Submitted to: Journal of Food Science
Publication Type: Other
Publication Acceptance Date: 11/9/2022
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Thank you for giving us the opportunity to reply to the letter you received about our paper entitled “Application of dairy-free vegetarian and vegan USDA food pattern models for non-pregnant, non-lactating healthy adults.” First, we’d like to thank Dr. Herby for raising her concerns about our paper to the editor so we can respond to them and clarify the points made in our manuscript. Primarily, we want to clarify what our study does- and does not- show. This publication is a proof of concept study, not a review paper, and its objective was to assess the feasibility of meeting recommendations in the 2020-2025 Dietary Guidelines for Americans (DGA) on an ovo-vegetarian or vegan diet. The 2020-2025 DGA recommends three dietary patterns— a Healthy Vegetarian Dietary Pattern (HVDP), a Healthy Mediterranean-Style Dietary Pattern, and a Healthy U.S.-Style Dietary Pattern. Even the DGA dietary patterns that include animal-source foods like meat, dairy, eggs, and poultry, will not meet recommendations for a few essential nutrients, including choline, vitamin E, and vitamin D, if followed perfectly. As with the dietary patterns in the DGA itself, our ovo-vegetarian and vegan adaptations- and the menus we crafted in this study to demonstrate how to follow them- do not meet all recommended levels of all essential nutrients. Our conclusion is not that ovo-vegetarian or vegan diets lack certain nutrients but rather that ovo-vegetarian and vegan diets specifically structured to align with the DGA may still be low in a few nutrients. Dr. Herby expresses concern regarding the amount of soy-based dairy alternatives in this menu and reliance on them as a source of protein. However, the soy milk and soy yogurt in these menus is not intended to be a protein food. The menus in this study were based on the DGA’s HVDP, which includes 3 cup-equivalents of the “dairy group” per day. Although there are several non-dairy alternatives on the market, fortified soy milk and soy yogurt are the only non-dairy alternatives included in the DGA’s dairy group. Therefore, our menu was limited by DGA recommendations to both include adequate daily amounts of the dairy group and adhere to the parameters of a vegan or ovo-vegetarian diet. A vegetarian or vegan diet may well provide adequate amounts of choline, vitamin D, zinc, and iron just like omnivorous diets may. Our article does not deny the possibility of crafting a vegetarian diet that meets those nutrient needs. However, this study was conducted to assess whether an ovo-vegetarian or vegan menu that aligned with recommendations in the DGA could meet recommendations for these nutrients. Therefore, we acknowledge that this menu does not contain enough choline to meet current recommendations. We do not address whether current nutrient recommendations are aligned with evidence or not, as that discussion is beyond the scope of this research. The potential detriments- or lack thereof- of consuming amounts of any nutrients below recommendations is also beyond the scope of this research. As Dr. Herby notes in her letter, sunlight is a natural source of vitamin D. It is quite challenging to consume enough vitamin D from food sources to meet recommendations. As we note earlier, even if the DGA dietary patterns were followed perfectly, they would not provide enough dietary vitamin D. Yet, as both you and Dr. Herby may have observed, we are based in North Dakota. Vitamin D is produced with exposure to UVB radiation, specifically. While enough UVB photons reach the surface during the spring, summer, and fall to enable vitamin D production, during winter, which is 6 months of the year in North Dakota (October to March), not enough UVB photons actually reach us to allow for cutaneous vitamin D production (Holick 2008). We felt it important to mention the potential insufficiency of vitamin D amounts in these dietary pat