The Association of the Proportion of Plant-Based Protein With Nutrient Deficiency Risk Among Older Adults in the US

Objectives: To evaluate the relationship between the proportion of plant-based protein (%PP) ratio and risk of nutrient deficiencies in older adults. Methods: Community dwelling individuals aged 65 or over were recruited for the Nutrition Interventions for Cognitive Enhancement (NICE) study in the Midwestern region of the US. All participants completed three-day food records and the records were entered into the Nutrition Data System for Research. Baseline data were used. Total protein, essential amino acids and fatty acids, dietary fibers, and all micronutrients were analyzed using logistic regression to predict deficiency risk (less than the US reference values for each nutrient). The resulting intercept and slope parameters from each model were extracted and used to estimate the predicted probability of deficiency for each nutrient as a function of %PP. Wald chi square values were also collected for these logistic regression parameters. Using linear regression, further exploration with the ratio allowed for an evaluation of whether the degree of deficiency was associated with %PP for those with no statistical relationship detected for %PP with nutrient deficiency. Results: Approximately 74% participants were female (age, 71.5 ± 4.9 years; n=205). The range of %PP was between 12.6 – 65.4%. For %PP >50, the probability of consuming less than protein requirement, which was calculated by 0.8g/kg, and vitamin B12 below an estimated average requirement (EAR) was 39.6% (p = 0.0033) and 29.3% (P < 0.0001), respectively. When %PP increased >60, a risk of protein and vitamin B12 inadequacy increased to 46.9% and 50.3%, respectively. Regardless of %PP, more than 80% of participants did not meet an EAR/adequate intake for choline, vitamin D, and potassium, and those consuming higher %PP had an increased risk of choline (p = 0.0007) and vitamin D (p = 0.0087) deficiencies. Conclusions: For adults 65 years old or over who consumed %PP >50, additional overall protein intake and the incorporation of vitamin B12 fortification/supplementation and/or animal protein may be necessary. In addition, choline, vitamin D, and potassium consumption needs to be increased regardless of %PP; in particular, ensuring increased consumption of choline and vitamin D is significant for higher %PP diets. Funding Sources: This work was funded by the National Institute of Health's National Institute on Aging.