Ultra-processed foods help vegans meet protein requirements
Limited research has shown that vegans consume more foods classified as ultra-processed by Nova than non-vegetarians, at least that was the conclusion of a French study published in 2021.1 This finding is unsurprising because nearly all plant-based meat and dairy alternatives are classified as ultra-processed foods (UPFs) whereas as their animal-based counterparts are classified as unprocessed or minimally processed foods.
In general, UPF intake is associated with a wide range of adverse health outcomes.2 However, this is not the case for all sub-categories of UPFs. For example, the results of a recently published cross-sectional analysis of the UK Biobank showed that the consumption of animal-based UPFs was associated with shorter leukocyte telomere length (LTL) whereas the consumption of vegetarian alternative UPFs was associated with increased length.3 Longer LTL is associated with longevity.4 UPFs also help meet protein requirements among adherents of plant-based diets, according to a newly published Brazilian cross-sectional study by Leitão et al.5
For this study, researchers analyzed the dietary intake of 774 (82.3% female) vegans with a median [interquartile range] age of 29 [24-35] years based on a self-administered 1-day food diary. Only 13.2% of total energy intake was derived from UPFs, which is extremely low compared to the intake of most other countries and lower than the average previously reported for Brazil.6
The median protein intake among the vegans was 1.12 g/kg/d, which significantly exceeds the RDA of 0.8 g/kg/d. The nutrient adequacy ratio for protein intake was 0.93. Nutrient adequacy is calculated by dividing nutrient intake by its recommendation (with scores being truncated at 1) for each participant and then finding the mean of values. Nutrient adequacy ratios were higher than 0.90 for all essential amino acids except for lysine, which was 0.90. Lysine is the limiting amino acid in grains. The second lowest nutrient adequacy ratio for essential amino acids was for methionine/cysteine at 0.93. Methionine and cysteine are the limiting amino acids in beans.
The percentage of total energy from protein primarily came from unprocessed and minimally processed foods (61.8%), followed by UPFs (23.6%), and processed foods (7.4%). Soy played a significant role in meeting protein needs. When textured soy protein was classified as unprocessed and minimally processed rather than as ultra-processed, the percentage of energy from protein derived from UPFs decreased from 23.6% to 14.3%. Furthermore, adjusted logistic regression models showed that consuming protein supplements and textured soy protein decreased the changes of inadequate protein intake by 94% and 68%, respectively. Conversely, unprocessed and minimally processed protein intake was associated with an increased probability of protein inadequacy.
Finally, Leitão et al.5 noted that soy is a challenging food item to classify given that there is significant variability in formulations with ingredients such as food additives and cosmetics. More importantly, they commented that it is hard to reconcile that textured soy protein would have detrimental health outcomes (despite its classification as ultra-processed) given the ample evidence suggesting otherwise. This observation holds true for protein supplements. Leitão et al.5 concluded that, at least with respect to individuals who adhere to a vegan diet, unrestricted advice to avoid UPFs may have unintended consequences, such as protein intake inadequacies.
References:
1. Gehring J, Touvier M, Baudry J, et al. Consumption of ultra-processed foods by pesco-vegetarians, vegetarians, and vegans: Associations with duration and age at diet initiation. J Nutr.2021;151(1):120-31. https://10.1093/jn/nxaa196
2. Lane MM, Gamage E, Du S, et al. Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ.2024;384(e077310. https://10.1136/bmj-2023-077310
3. Li C, Zhang Y, Zhang K, et al. Association between ultraprocessed foods consumption and leucocyte telomere length: A cross-sectional study of UK Biobank. J Nutr.2024. https://10.1016/j.tjnut.2024.05.001
4. Arbeev KG, Verhulst S, Steenstrup T, et al. Association of Leukocyte Telomere Length With Mortality Among Adult Participants in 3 Longitudinal Studies. JAMA Netw Open.2020;3(2):e200023. https://10.1001/jamanetworkopen.2020.0023
5. Leitao AE, Esteves GP, Mazzolani BC, et al. Protein and amino acid adequacy and food consumption by processing level in vegans in Brazil. JAMA Netw Open.2024;7(6):e2418226. https://10.1001/jamanetworkopen.2024.18226
6. Touvier M, da Costa Louzada ML, Mozaffarian D, et al. Ultra-processed foods and cardiometabolic health: public health policies to reduce consumption cannot wait. BMJ.2023;383(e075294. https://10.1136/bmj-2023-075294
This blog is supported by SNI Global and U.S. Soy.