Evaluation of Protein Adequacy From Plant-Based Dietary Scenarios in Simulation Studies: A Narrative Review

Although a diet high in plant foods can provide beneficial nutritional outcomes, unbalanced and restrictive plant-based diets may cause nutrient deficiencies. Protein intake from these diets is widely discussed, but the comparison of animal and plant proteins often disregards amino acid composition and digestibility as measurements of protein quality. Poor provision of high-quality protein may result in adverse outcomes, especially for individuals with increased nutrient requirements. Several dietary modeling studies have examined protein adequacy when animal-sourced proteins are replaced with traditional and novel plant proteins, but no review consolidating these findings are available. This narrative review aimed to summarize the approaches of modeling studies for protein intake and protein quality when animal-sourced proteins are replaced with plant foods in diet simulations and examine how these factors vary across age groups. A total of 23 studies using dietary models to predict protein contribution from plant proteins were consolidated and categorized into the following themes-protein intake, protein quality, novel plant-based alternatives, and plant-based diets in special populations. Protein intake from plant-based diet simulations was lower than from diets with animal-sourced foods but met country-specific nutrient requirements. However, protein adequacy from some plant-sourced foods were not met for simulated diets of children and older adults. Reduced amino acid adequacy was observed with increasing intake of plant foods in some scenarios. Protein adequacy was generally dependent on the choice of substitution with legumes, nuts, and seeds providing greater protein intake and quality than cereals. Complete replacement of animal to plant-sourced foods reduced protein adequacy when compared with baseline diets and partial replacements.

Effect of Adding Pulses to Replace Protein Foods and Refined Grains in Healthy Dietary Patterns

Pulses are dry seeds of legumes which are high in fiber and contain plant protein and several important macronutrients. Our aim was to model the nutritional effects of substituting servings of protein foods and/or refined grains with servings of beans and peas in the Healthy U.S.-Style Pattern identified in the Dietary Guidelines for Americans, 2020-2025. Dietary modeling was accomplished by substituting nutrients of protein foods and/or refined grains with nutrients of the USDA's beans and peas (pulses) composite in the 2000 kcal Healthy U.S.-Style Pattern. A 10% or more change was used as an indicator of meaningful differences. Cost implications were computed by adding the cost of pulses and subtracting the cost of protein foods/refined grains according to the modeling scenario. The substitution of 6-8 oz/week protein foods with 1.5-2.0 cups/week pulses increased fiber and decreased cholesterol. Higher amounts of pulses replacing refined grains or combinations of protein foods and refined grains generally increase fiber, iron, magnesium, potassium, and copper depending on the modeling scenarios. All modeling scenarios of substituting the servings of protein foods alone or in combination with refined grains with the servings of pulses were associated with cost savings. Our results suggest that encouraging increased pulse consumption may be an effective strategy for improving diet.

Iron-Fortified Foods Are Needed To Meet the Estimated Average Requirement for Iron in Australian Infants Aged 6 to 12 Months

BACKGROUND

Meeting iron intake recommendations is challenging for infants 6-12 mo, especially breastfed infants. Three-quarters of Australian infants 6-12 mo have iron intakes below the estimated average requirement (7 mg), placing them at risk of iron deficiency. After 6 mo, breastmilk is no longer sufficient to meet the increased demand for iron, and iron-rich complementary foods are recommended. Iron-fortified foods may be a means of improving iron intake in infants, particularly those that are breastfed.

OBJECTIVES

The aims of the study were as follows: 1) to examine the effect of milk-type and fortified foods on iron intake and the prevalence of inadequacy in infants 6-12 mo; 2) to model the effect of fixed amounts of iron-fortified infant cereal (IFIC) at 6 levels of iron fortification on total iron intake and the prevalence of inadequacy; and 3) to assess the effect IFIC on the intake of other nutrients in the diet.

DESIGN

Secondary analysis of cross-sectional dietary intake data of infants 6-12 mo (n = 286) participating in the Australian Feeding Infants and Toddlers Study (OzFITS) 2021.

RESULTS

Median (interquartile range) iron intake was 8.9 (7.5, 10.3); 6.3 (4.5, 8.2); and 2.7 (1.5, 4.4) mg/d in formula-fed, combination-fed, and breastfed infants, respectively. The corresponding prevalence of inadequacy was 19%, 67%, and 96%. Infants who consumed fortified foods had higher median iron intakes than those who did not, 6.2 compared with 1.9 mg/d. Dietary modeling showed that consuming 18 g (300 kJ) of IFIC, fortified at 35 mg/100 g dry weight, reduces the prevalence of inadequacy for iron from 75% to 5% for all infants.

CONCLUSIONS

Iron intakes are low in Australian infants, especially for breastfed infants in the second half of infancy. Modeling shows that 300 kJ of IFIC, the current manufacturer-recommended serving, fortified at 35 mg/100 g dry weight, added to infant diets would be an effective means to reduce the prevalence of inadequacy for iron.

Corrigendum: Micronutrient intake inadequacies in different types of milk consumers in Indonesian children 1-5 years: dietary modeling with young child milk improved nutrient intakes

[This corrects the article DOI: 10.3389/fnut.2023.1169904.].

Micronutrient intake inadequacies in different types of milk consumers in Indonesian children 1–5 years: dietary modeling with young child milk improved nutrient intakes

Background

Indonesian children under-five have a high prevalence of micronutrient deficiencies. Improving young child feeding practices may be the solution. Increasing the consumption of appropriate milk products could help to reduce nutrient inadequacy.

Methods

The objective of this study was to assess nutrient inadequacy in Indonesian children to evaluate the potential improvement using dietary modeling analysis. Data from children aged 1-5 years from the Indonesian Individual Dietary Consumption Survey in 2014 were used in this analysis (n = 11,020). Diet modeling was conducted in two scenarios, substitution volume to volume and calories to calories.

Results

The proportion of children consuming young child milk (YCM) was the highest compared to other milk types across all age groups, followed by condensed milk and cow's milk. YCM, also called "Growing-Up Milk" (GUM), are marketed as a product specifically formulated for the nutritional needs of young children. YCM consumers had lower prevalence of inadequate intakes in iron, zinc, vitamins A, C and D across age groups when compared to condensed milk consumers. The prevalence of inadequate intakes of nutrients in condensed milk consumers was Vitamin A (67, 64%), folate (92, 91%), Vitamin D (87, 84%), iron (84, 76%), and zinc (76, 76%) in 1-2y and 3-4y, respectively. The substitution of condensed milk with a YCM reduced the prevalence of inadequate intakes of micronutrients, such as Vitamin A, vitamin D, folate, iron and zinc, which are important for immune function. YCM reduced the prevalence of inadequate intakes of micronutrients by 20-40% (Vit A and folate) and 40-50% (Vit D and zinc). The reduction of prevalence of inadequate iron intake was 31% in 1-2y and 63% in 3-4y.

Conclusion

The prevalence of inadequate micronutrient intakes was high among children aged 1-5 years old in Indonesia. YCM consumers had better nutrient intake. The substitution of condensed milk with a YCM reduced the prevalence of inadequate of micronutrient intake. Thus, nutrient intakes could be improved by YCM consumption in 1-5 years old children in Indonesia, along with nutrition education on feeding practices.

Vitamin D Biofortification of Pork May Offer a Food-Based Strategy to Increase Vitamin D Intakes in the UK Population

Hypovitaminosis D is prevalent worldwide, with many populations failing to achieve the recommended nutrient intake (RNI) for vitamin D (10-20 μg/day). Owing to low vitamin D intakes, limited exposure to ultraviolet-B (UVB) induced dermal synthesis, lack of mandatory fortification and poor uptake in supplement advice, additional food-based strategies are warranted to enable the UK population to achieve optimal vitamin D intakes, thus reducing musculoskeletal risks or suboptimal immune functioning. The aims of the current study were to (1) determine any changes to vitamin D intake and status over a 9-year period, and (2) apply dietary modeling to predict the impact of vitamin D biofortification of pork and pork products on population intakes. Data from the UK National Diet and Nutrition Survey (Year 1-9; 2008/09-2016/17) were analyzed to explore nationally representative mean vitamin D intakes and 25-hydroxyvitamin D (25(OH)D) concentrations (n = 13,350). Four theoretical dietary scenarios of vitamin D pork biofortification were computed (vitamin D content +50/100/150/200% vs. standard). Vitamin D intake in the UK population has not changed significantly from 2008 to 2017 and in 2016/17, across all age groups, 13.2% were considered deficient [25(OH)D <25 nmol/L]. Theoretically, increasing vitamin D concentrations in biofortified pork by 50, 100, 150, and 200%, would increase vitamin population D intake by 4.9, 10.1, 15.0, and 19.8% respectively. When specifically considering the impact on gender and age, based on the last scenario, a greater relative change was observed in males (22.6%) vs. females (17.8%). The greatest relative change was observed amongst 11-18 year olds (25.2%). Vitamin D intakes have remained stable in the UK for almost a decade, confirming that strategies are urgently required to help the population achieve the RNI for vitamin D. Biofortification of pork meat provides a proof of concept, demonstrating that animal-based strategies may offer an important contribution to help to improve the vitamin D intakes of the UK population, particularly adolescents.

Potassium chloride-based replacers: modeling effects on sodium and potassium intakes of the US population with cross-sectional data from NHANES 2015-2016 and 2009-2010

BACKGROUND

Sodium intake in the USA exceeds recommendations. The replacement of added sodium chloride (NaCl) with potassium chloride (KCl) provides a potential strategy to reduce sodium intake.

OBJECTIVE

The purpose of this study was to quantitatively estimate changes in intakes of sodium and potassium by the US population assuming use of potassium-based NaCl replacers in top dietary sodium sources.

METHODS

Data collected in the What We Eat in America (WWEIA) component of the 2015-2016 and 2009-2010 NHANES were used to identify top-ranking sources of dietary sodium among the population aged 2 y and older based on contributions from food categories aligning with the FDA draft guidance for voluntary sodium reduction. Predicted nutrient intakes were estimated in models assuming total and feasible and practical (F&P) replacement of added NaCl with KCl in foods and ingredients within the top food sources of sodium. An expert elicitation was conducted to collect information on the F&P KCl replacement of added NaCl.

RESULTS

Using 2015-2016 consumption data, the total replacement of added NaCl with KCl in the 18 top-ranking sources of dietary sodium results in a predicted sodium intake of 2004 mg/d from the replacement of 1406 mg/d sodium with 1870 mg/d potassium as KCl. Modeled F&P replacement predicted sodium intakes of 3117 mg/d (range of 2953 to 3255 mg/d) from the replacement of 294 mg/d sodium (155 to 457 mg/d) with 390 mg/d potassium (206 to 608 mg/d). Similar results are seen with 2009-2010 data.

CONCLUSIONS

The F&P replacement of NaCl with KCl in top-ranking sources of dietary sodium modeled in this study can result in decreased sodium to a level consistent with the short-term intake goal targeted by the FDA of 3000 mg/d, with the mean potassium intake remaining in the range recommended for the apparently healthy population.

Introduction to the SIMPLE Macro, a Tool to Increase the Accessibility of 24-Hour Dietary Recall Analysis and Modeling

BACKGROUND

Information on long-term dietary intake is often required for research or program planning, but surveys routinely use short-term assessments such as 24-h recalls (24HRs). Methods to reduce the impact of within-person variation in 24HRs, such as the National Cancer Institute (NCI) method, typically require extensive training and skill.

OBJECTIVES

We introduce the Simulating Intake of Micronutrients for Policy Learning and Engagement (SIMPLE) macro, a new tool to increase the accessibility of 24HR analysis. We explain the underlying theory behind the tool and provide examples of potential applications.

METHODS

The SIMPLE macro connects the core NCI statistical code to estimate usual intake distributions and includes additional code to enable advanced analyses such as predictive modeling. The related SIMPLE-Iron macro applies the full probability method to estimate inadequate iron intake, and the SIMPLE-1D macro is used for descriptive or modeling analyses of data with a single 24HR per person. The macros and associated documentations are freely available. We analyzed data from the US National Health and Nutrition Examination Survey (NHANES) and the Cameroon National Micronutrient Survey to compare the SIMPLE macro to 1) the core NCI code using the Estimated Average Requirement cut point method, and 2) the IMAPP software for iron only, and to demonstrate the applications of the SIMPLE macro for estimating usual intake and predictive modeling.

RESULTS

The SIMPLE macro generates identical results to the core NCI code. The SIMPLE-Iron macro also produces estimates of inadequate iron intake comparable to the IMAPP software. The examples demonstrate application of the SIMPLE macro to 1) descriptive analyses of nutrient intake from food and supplements (NHANES), and 2) analyses accounting for breast-milk nutrient intake and modeling fortification and supplementation programs (Cameroon).

CONCLUSIONS

The SIMPLE macros may facilitate the analysis and modeling of dietary data to inform nutrition research, programs, and policy.

Micronutrient Fortification of Commercially Available Biscuits Is Predicted to Have Minimal Impact on Prevalence of Inadequate Micronutrient Intakes: Modeling of National Dietary Data From Cameroon

BACKGROUND

Voluntarily fortified snack products are increasingly available but are not necessarily formulated to meet known dietary nutrient gaps, so potential impacts on population micronutrient intake adequacy are uncertain.

OBJECTIVES

We modeled the impacts of hypothetical micronutrient-fortified biscuits on inadequate micronutrient intake in children and women of reproductive age (WRA) in Cameroon.

METHODS

In a nationally representative survey stratified by macro-region (North, South, and Yaoundé/Douala), 24-h dietary recall data were collected from 883 children aged 12-59 mo and from 912 WRA. We estimated usual nutrient intake by the National Cancer Institute method for vitamin A, folate, vitamin B-12, zinc, and iron. We simulated the impact of biscuit fortification on prevalence of micronutrient intake below the estimated average requirement, given observed biscuit consumption, in the presence and absence of large-scale food fortification (LSFF) programs.

RESULTS

Biscuit consumption in the prior 24-h by children and WRA, respectively, ranged from 4.5% and 1.5% in the South, to 20.7% and 5.9% in Yaoundé/Douala. In the absence of LSFF programs, biscuits fortified with retinol (600 μg/100 g), folic acid (300 μg/100 g), and zinc (8 mg/100 g) were predicted to reduce the prevalence of inadequacy among children by 10.3 ± 4.4, 13.2 ± 4.2, and 12.0 ± 6.1 percentage points, respectively, in Yaoundé/Douala. However, when existing vitamin A-fortified oil, and folic acid-fortified and zinc-fortified wheat flour programs were considered, the additional impacts of fortified biscuits were reduced substantially. Micronutrient-fortified biscuits were predicted to have minimal impact on dietary inadequacy in WRA, with or without LSFF programs.

CONCLUSIONS

Given observed patterns of biscuit consumption in Cameroon, biscuit fortification is unlikely to reduce dietary inadequacy of studied micronutrients, except possibly for selected nutrients in children in urban areas in the absence of LSFF programs. As voluntary fortification becomes increasingly common, modeling studies could help guide efforts to ensure that fortified products align with public health goals.

Contribution of 100% Fruit Juice to Micronutrient Intakes in the United States, United Kingdom and Brazil

The contribution of 100% fruit juice (FJ) to the total daily intakes of energy, sugars, and select vitamins and minerals and to the recommended dietary allowances (RDAs) or adequate intake (AI) of these micronutrients was assessed in individuals reporting the consumption of 100% FJ in the national dietary intake surveys of the United States (U.S.; n = 8661), the United Kingdom (UK; n = 2546) and Brazil (n = 34,003). Associations of 100% FJ intake with the odds of being overweight or obese also were assessed. Data from the U.S. National Health and Nutrition Examination Survey (2013–2014), the UK National Diet and Nutrition Survey (2012–2014), and Brazil’s Pesquisa de Orçamentos Familiares (2008–2009) were used, and all analyses were limited to individuals reporting consumption of 100% FJ on at least one day of the dietary intake survey. Approximately 34%, 37%, and 42% of individuals surveyed reported the consumption of 100% FJ on at least one day of the dietary intake survey in the U.S., UK, and Brazil, respectively, and the average daily intakes of 100% FJ were 184 g, 130 g, and 249 g, respectively. Across the 3 countries, 100% FJ contributed to 3–6% of total energy intakes, 12–31% of total sugar intakes, 21–54% of total vitamin C intakes, 1–12% of total vitamin A intakes, 4–15% of total folate intakes, 7–17% of total potassium intakes, 2–7% of total calcium intakes, and 4–12% of total magnesium intakes. In a multivariate logistic regression model, juice intake was associated with a significant reduction in the odds of being overweight or obese in UK adults (OR = 0.79; 0.63, 0.99), and significant increases in the odds of being overweight or obese in UK children (OR = 1.16; 1.01, 1.33) and Brazilian adults (OR = 1.04; 1.00, 1.09). Nutrient contributions of 100% FJ vary according to regional intake levels. In all three countries studied, 100% FJ contributed to more than 5% of the RDAs for vitamin C and folate. In the U.S. and Brazil, 100% FJ contributed to more than 5% of the RDA for magnesium and more than 5% of the AI for potassium.

Intake of 100% Fruit Juice Is Associated with Improved Diet Quality of Adults: NHANES 2013-2016 Analysis

Fruit intake is generally associated with better diet quality and overall health. This report examined the effect of 100% fruit juice (considered a part of total fruit servings) and its replacement with whole fruits equivalents on nutrient intake and diet quality. National Health and Nutrition Examination Survey 2013-2016 data (24-h dietary recall) from adults 19+ years (n = 10,112) were used to assess the diet quality and nutrient intakes and to isocalorically replace with 100% fruit juice intakes whole fruit equivalents in a modeling analysis. About 15.6% adults were 100% fruit juice consumers. Consumers had higher diet quality (10% higher Healthy Eating Index, HEI 2015 score), and higher intakes of energy, calcium, magnesium, potassium, vitamin C and vitamin D than non-consumers. Consumption of 100% fruit juice was also associated with lower risk of being overweight/obese (-22%) and having metabolic syndrome (-27%). Replacing 100% fruit juice with whole fruits equivalents did not affect nutrient intake except for a modest increase (+6.4%) in dietary fiber. Results show that 100% fruit juice intake was associated with better diet quality and higher nutrient intake. Replacement of 100% fruit juice intake with whole fruits equivalents had no significant effect on nutrients except for dietary fiber.

Small Increments in Vitamin D Intake by Irish Adults over a Decade Show That Strategic Initiatives to Fortify the Food Supply Are Needed

BACKGROUND

Food fortification could be an effective method of increasing vitamin D intakes and preventing deficiency with minimal risk of excessive dosing.

OBJECTIVE

Secular trends in vitamin D intakes were examined over a 10-y period.

METHODS

We compared vitamin D intakes among 18- to 64-y-old adults from the base diet, fortified foods, and supplements in 2 nationally representative dietary surveys in 1999 and 2009 implemented using the same methodology.

RESULTS

There was a slight increase in the median (IQR) intake of vitamin D from 2.9 (3.2) to 3.5 (3.7) μg/d (mean ± SD, 4.3 ± 4.0 to 5.0 ± 6.4 μg). The median (IQR) intake from the base diet was 2.3 (1.6) μg/d in 1999 and 2.1 (1.8) μg/d in 2009. In vitamin D supplement users, median (IQR) intakes were 7.6 (6.7) and 8.7 (7.2) μg/d and the prevalence of inadequacy decreased from 67% to 57% in 2009. Although the consumption of vitamin D-containing supplements was similar in the 2 surveys (17% and 16%), the use of calcium-vitamin D supplements increased from 3% to 10% among women aged 50-64 y. The prevalence of fortified food consumption was also similar at 60%, and median (IQR) vitamin D intakes in consumers were 2.9 (2.2) and 3.7 (2.9) μg/d in 1999 and 2009, respectively. Mathematical modeling of food fortification using modified vitamin D composition data showed that there is potential to increase vitamin D intakes at the lower end of the distribution, without increasing the risk of exceeding the Tolerable Upper Intake Level.

CONCLUSIONS

We report small increases in vitamin D intakes among Irish adults over a decade of focus on vitamin D and in the context of a voluntary fortification policy. Strategic management of vitamin D in the food supply is required to yield measurable benefits.