Protein Quality Assessment of Follow-up Formula for Young Children and Ready-to-Use Therapeutic Foods: Recommendations by the FAO Expert Working Group in 2017.

The FAO of the UN convened an Expert Working Group meeting to provide recommendations related to protein quality evaluation of Follow-up Formula for Young Children (FUF-YC) and Ready-to-Use Therapeutic Foods (RUTFs). The protein and amino acid (AA) scoring patterns for the target age groups were defined and recommendations provided on the use of currently available protein and indispensable AA digestibility data. For FUF-YC, an age category of 1-2.9 y was identified, and a matching protein requirement of 0.86 g · kg-1 · d-1 with corresponding AA requirements were recommended. For RUTF, the protein requirement recommended was 2.82 g · kg-1 · d-1, to achieve a catch-up weight gain of 10 g · kg-1 · d-1 in children recovering from severe acute malnutrition. The AA requirements were factorially derived based on the adult protein requirement for maintenance and tissue AA composition. A flowchart was proposed for the best available methods to estimate digestibility coefficients (of either protein or AAs), in the following order: human, growing pig, and rat true ileal AA digestibility values. Where this is not possible, fecal protein digestibility values should be used. The Expert Working Group recommends the use of the Protein Digestibility Corrected Amino Acid Score (PDCAAS), with existing protein digestibility values, or the Digestible Indispensable Amino Acid Score provided that individual AA digestibility values are available for protein quality evaluation using the latter score. The Group also recommends the use of ileal digestibility of protein or of AAs for plant-based protein sources, recognizing the possible effects of antinutritional factors and impaired gut function. A PDCAAS score of ≥90% can be considered adequate for these formulations, whereas with a score <90%, the quantity of protein should be increased to meet the requirements. Regardless of the protein quality score, the ability of formulations to support growth in the target population should be evaluated. Future research recommendations are also proposed based on the knowledge gaps identified.

Ruminal degradation and estimated energy and protein values for ruminants of Durum wheat varieties grown in three locations.

Durum wheat is mainly used in pasta production, but may also be used as animal feed, for example as concentrate for dairy cows. Data on the ruminal degradation of Durum grains are scarce. Hence, the objective of the present study was to describe ruminal in situ crude protein (CP) and starch (ST) degradation, to investigate in vitro gas production kinetics, and to estimate utilisable CP at the duodenum (uCP) in vitro of five Durum varieties from three growing locations. Metabolisable energy (ME) and digestibility of organic matter (dOM) were also estimated using in vitro data. In situ incubations were conducted in three lactating jersey cows over defined timespans from 1 to 72 hr. Ruminal degradation parameters were estimated using exponential regression, and effective ruminal degradation was predicted for a ruminal passage rate of 8%/hr (ED8 ). In situ CP (a = 11%-19%; b = 80%-88%; c = 23%-33%/hr) and ST (a = 22%-39%; b = 60%-78%; c = 61%-123%/hr) degradation kinetics varied among samples and were influenced by location. Some samples showed a remarkably high ST degradation rate of up to 123%/h, which can significantly influence rumen pH and health when high amounts are incorporated into dairy rations. However, the ED of CP (77%-82%) and ST (91%-95%), and the in vitro estimates of ME (13.6-14.1 MJ/kg DM), dOM (92%-96%), and uCP (183-195 k/g DM) varied within a relatively small range. Hence, it may be adequate to use the mean values of these Durum grain characteristics when rations for ruminants are calculated and a differentiation depending on variety and location may not be necessary.

Importance of maternal diet in the training of the infant's immune system during gestation and lactation.

Latest forecasts predict that half of the European population will be allergic within the coming 15 years, with food allergies contributing substantially to the total burden; preventive measures are urgently needed. Unfortunately, all attempted alimentary strategies for primary prevention of allergic diseases through allergen avoidance so far have failed. This also holds true for the prevention of food allergies in breastfed infants by the common practice of excluding certain foods with allergenic potential from the maternal diet. As a preventive measure, therefore, exclusion diets should be discouraged. They can exhaust nursing mothers and negatively impact both their nutritional status as well as their motivation to breastfeed. A prolonged exclusion diet may be indicated solely in cases of doctor-diagnosed food allergy following rigid medical tests (e.g. double-blind placebo-controlled food challenges). Indicated cases usually involve exclusion of only a few food items. Continued breastfeeding is generally important for many aspects of the infant's health, including the training of the infant's immune responses to foreign compounds and avoidance of overshooting inflammatory responses. Recent studies suggest that the presence of maternal dietary proteins in amniotic fluid, cord blood, and human milk might support the induction of tolerance towards solid foods in infants. These are exactly the same species of proteins or remnants thereof that, in comparatively few cases, trigger allergic responses. However, the insight that the proteins of maternal dietary origin in human milk are more likely to be cure (or, more precise, directing prevention) than curse has still largely evaded the attention of health care professionals consulted by worried breastfeeding mothers. In this paper, we summarize recent literature on the importance of exposure to dietary proteins in the establishment of immunological tolerance and hence prevention of allergic disease. Multiple organizations have used the scientific knowledge to build (local) guidelines (e.g. AAAAI, EAACI, BSACI) that can support health care professionals to provide the best strategy to prevent the onset of allergic diseases. We thus hope to clarify existing confusion about the allergenic propensities of dietary proteins during early life, which has contributed to exaggerated fears around the diet of pregnant and breastfeeding mothers.

Low-protein diet-induced hyperphagia and adiposity are modulated through interactions involving thermoregulation, motor activity, and protein quality in mice.

Low protein (LP)-containing diets can induce overeating in rodents and possibly in humans in an effort to meet protein requirement, but the effects on energy expenditure (EE) are unclear. The present study evaluated the changes induced by reducing dietary protein from 20% to 6%-using either soy protein or casein-on energy intake, body composition, and EE in mice housed at 22°C or at 30°C (thermal neutrality). LP feeding increased energy intake and adiposity, more in soy-fed than in casein-fed mice, but also increased EE, thus limiting fat accumulation. The increase in EE was due mainly to an increase in spontaneous motor activity related to EE and not to thermoregulation. However, the high cost of thermoregulation at 22°C and the subsequent heat exchanges between nonshivering thermogenesis, motor activity, and feeding induced large differences in adaptation between mice housed at 22°C and at 30°C.

Protein quality & amino acid requirements in relation to needs in India.

The relevance of protein and its constituent amino acids (AAs) in the structure and function of the human body is well known. Accumulating evidence has conferred specific functional and regulatory roles for individual AAs, adding relevance to their requirements across different age groups. The methods for measuring AA requirements have progressed from the classical nitrogen balance to the current stable isotope-based AA balance methods. Requirements of most of the indispensable AA (IAA) have been estimated in healthy Indian population by the best available balance method and has shown to be higher than earlier 1985 WHO/FAO/UNU (World Health Organization/Food and Agriculture Organization/United Nations University) recommendations. In addition, potential changes in the requirement, through adaptation to chronic undernutrition or to infection, have also been evaluated. In 2007, the WHO/FAO/UNU released a recommendation that increased the daily IAA requirement, based on primary evidence from Indian balance studies. This meant that to ensure that the new IAA requirements were met, individual foods or mixed diets needed to be assessed for their protein quality, or their ability to deliver the required amount of IAA. The recent FAO report on protein quality evaluation recommends the use of a new chemical AA score, the digestible IAA score (DIAAS), to replace the earlier protein digestibility corrected AA score. The DIAAS requires the determination of individual AA digestibility at the ileal level. A minimally invasive dual stable isotope tracer-based approach has been developed in India and has been used to determine digestibility of various foods in Indian adults and children. The increase in IAA requirements and subsequent protein quality requirements have implications for national regulatory frameworks, growth and development, and in turn, for economic and agricultural policy.

Sufficient Protein Quality of Food Aid Varies with the Physiologic Status of Recipients.

Protein quality scores use the amino acid (AA) requirements of a healthy North American child. AA requirements vary with physiologic status. We estimated AA requirements for healthy North American children, children with environmental enteric dysfunction, children recovering from wasting, and children with an acute infection. The protein quality of food aid products was then calculated to determine whether it was sufficient in all these groups, and we found that it may not be adequate for all of them. Physiologic status is important when assessing the protein quality of food aid. Rates of weight gain from 8 published trials treating children with moderate acute malnutrition were abstracted, and protein quality scores from the corresponding food aid products were calculated with the use of the digestible indispensable amino acid score (DIAAS). Two DIAAS values were calculated, one in healthy children aged 1-3 y as a reference population and the other in malnourished children aged 1-3 y as a reference population. These data were used to calculate the best fit regression line between weight gain and protein quality. The slope of the regression line was greater when malnourished children were used as a reference population than when healthy children were used (0.128; 95% CI: 0.118, 0.138 compared with 0.097; 95% CI: 0.090, 0.105 measured in g · kg-1 · d-1 · DIASS U-1). These findings suggest that adjusting AA requirements for physiologic status may more accurately estimate the minimum protein quality of food aid products.

Amino Acid Absorption in the Large Intestine of Humans and Porcine Models.

Dietary protein quality has been recognized as a critical issue by international authorities because it can affect important functions of the body. To predict protein quality, the FAO introduced the Digestible Indispensable Amino Acid Score. This score depends on ileal amino acid (AA) digestibility; therefore, the assumption is made that AAs are not absorbed in nutritionally relevant amounts from the large intestine. This article reviews the evidence for this assumption by considering the role of the mammalian large intestine in dietary protein and AA digestion and absorption, with particular reference to adult humans. Although most dietary AAs and peptides are absorbed in the small intestine, substantial amounts can enter the large intestine. Nitrogen is absorbed in the large intestine, and a series of animal experiments indicate a potential small degree of AA absorption. In humans, colonocytes have the capacity for AA absorption because AA transporters are present in the large intestine. The absorption of nutritionally relevant amounts of dietary indispensable AAs and peptides in the human large intestine has not been convincingly demonstrated, however.

Dietary Protein Intake in Young Children in Selected Low-Income Countries Is Generally Adequate in Relation to Estimated Requirements for Healthy Children, Except When Complementary Food Intake Is Low.

Background: Previous research indicates that young children in low-income countries (LICs) generally consume greater amounts of protein than published estimates of protein requirements, but this research did not account for protein quality based on the mix of amino acids and the digestibility of ingested protein.Objective: Our objective was to estimate the prevalence of inadequate protein and amino acid intake by young children in LICs, accounting for protein quality.Methods: Seven data sets with information on dietary intake for children (6-35 mo of age) from 6 LICs (Peru, Guatemala, Ecuador, Bangladesh, Uganda, and Zambia) were reanalyzed to estimate protein and amino acid intake and assess adequacy. The protein digestibility-corrected amino acid score of each child's diet was calculated and multiplied by the original (crude) protein intake to obtain an estimate of available protein intake. Distributions of usual intake were obtained to estimate the prevalence of inadequate protein and amino acid intake for each cohort according to Estimated Average Requirements.Results: The prevalence of inadequate protein intake was highest in breastfeeding children aged 6-8 mo: 24% of Bangladeshi and 16% of Peruvian children. With the exception of Bangladesh, the prevalence of inadequate available protein intake decreased by age 9-12 mo and was very low in all sites (0-2%) after 12 mo of age. Inadequate protein intake in children <12 mo of age was due primarily to low energy intake from complementary foods, not inadequate protein density.Conclusions: Overall, most children consumed protein amounts greater than requirements, except for the younger breastfeeding children, who were consuming low amounts of complementary foods. These findings reinforce previous evidence that dietary protein is not generally limiting for children in LICs compared with estimated requirements for healthy children, even after accounting for protein quality. However, unmeasured effects of infection and intestinal dysfunction on the children's protein requirements could modify this conclusion.

Values for digestible indispensable amino acid scores (DIAAS) for some dairy and plant proteins may better describe protein quality than values calculated using the concept for protein digestibility-corrected amino acid scores (PDCAAS).

An experiment was conducted to compare values for digestible indispensable amino acid scores (DIAAS) for four animal proteins and four plant proteins with values calculated as recommended for protein digestibility-corrected amino acid scores (PDCAAS), but determined in pigs instead of in rats. Values for standardised total tract digestibility (STTD) of crude protein (CP) and standardised ileal digestibility (SID) of amino acids (AA) were calculated for whey protein isolate (WPI), whey protein concentrate (WPC), milk protein concentrate (MPC), skimmed milk powder (SMP), pea protein concentrate (PPC), soya protein isolate (SPI), soya flour and whole-grain wheat. The PDCAAS-like values were calculated using the STTD of CP to estimate AA digestibility and values for DIAAS were calculated from values for SID of AA. Results indicated that values for SID of most indispensable AA in WPI, WPC and MPC were greater (P<0·05) than for SMP, PPC, SPI, soya flour and wheat. With the exception of arginine and tryptophan, the SID of all indispensable AA in SPI was greater (P<0·05) than in soya flour, and with the exception of threonine, the SID of all indispensable AA in wheat was less (P<0·05) than in all other ingredients. If the same scoring pattern for children between 6 and 36 months was used to calculate PDCAAS-like values and DIAAS, PDCAAS-like values were greater (P<0·05) than DIAAS values for SMP, PPC, SPI, soya flour and wheat indicating that PDCAAS-like values estimated in pigs may overestimate the quality of these proteins.

Research Approaches and Methods for Evaluating the Protein Quality of Human Foods Proposed by an FAO Expert Working Group in 2014.

The Protein Digestibility Corrected Amino Acid Score (PDCAAS) has been adopted for assessing protein quality in human foods since 1991, and the shortcomings of using the PDCAAS have been recognized since its adoption. The 2011 FAO Expert Consultation recognized that the Digestible Indispensable Amino Acid Score (DIAAS) was superior to the PDCAAS for determining protein quality. However, there were insufficient human data on amino acid digestibility before adopting the DIAAS. More human data were needed before DIAAS could be implemented. In 2014, FAO convened an expert working group to propose and agree on research protocols using both human-based assays and animal models to study ileal amino acid digestibility (metabolic availability) of human foods. The working group identified 5 research protocols for further research and development. A robust database of protein digestibility of foods commonly consumed worldwide, including those consumed in low-income countries, is needed for an informed decision on adopting the DIAAS. A review on the impacts of using the DIAAS on public health policies is necessary. It would be advantageous to have a global coordinating effort to advance research and data collection. Collaboration with international and national agriculture institutes is desirable. Opportunities should be provided for young researchers, particularly those from developing countries, to engage in protein-quality research for sustainable implementation of DIAAS. To conclude, the DIAAS is a conceptually preferable method compared with the PDCAAS for protein and amino acid quality evaluation. However, the complete value of the DIAAS and its impact on public health nutrition cannot be realized until there are sufficient accumulated ileal amino acid digestibility data on human foods that are consumed in different nutritional and environmental conditions, measured by competent authorities. A future meeting may be needed to evaluate the size and quality of the data set and to determine the timeline for full adoption and implementation of the DIAAS.

Multipoint near-infrared spectrometry for real-time monitoring of protein conformational stability in powdered infant formula.

Powdered infant formula (PIF) can be the sole source of nutrition for babies and infants. Monitoring conformational changes in protein during manufacture of PIF is critical in order to maintain its nutritional value. This study presents the development of a calibration model for monitoring conformational changes in PIF protein by applying a novel multipoint near-infrared (NIR) spectrometry. NIR spectra were collected for PIF and PIF proteins, casein and whey protein isolate, before and after heat treatment. Results show that principal component analysis showed discrimination between native protein at room temperature and protein conformational changes caused at elevated temperature. Partial least squares regression analysis showed good calibration models with correlation coefficients ranging between 87% and 99% for the prediction of protein quality. This novel multipoint NIR spectrometry could serve as a simple in-line tool to rapidly monitor protein quality during processing stages, contributing to product nutritional value.

Effects of different dietary protein levels and DL-methionine supplementation on hair growth and pelt quality in mink (Neovision vision).

The effect of different dietary protein levels and DL-methionine (Met) supplementation on hair growth and the resulting pelt quality in mink was studied. Four groups of male mink were fed with four isocaloric diets containing 32% (P32), 24% (P24), 16% (P16) or P24+Met (0.8%) crude protein of dry matter (DM) from September to December. Skin biopsies were taken at the pelting. Histological techniques and computer-assisted light microscopy were used to determine the ratio of activity (ROA) of under hairs and guard hairs respectively. The results showed that when the dietary protein level reduced from 32% to 16%, body length, number and diameter of under hairs and guard hairs of minks declined, and pelt length and pelt weight of minks decreased significantly (p < 0.05). These parameters were similar between P32 and P24 with Met supplementation (p > 0.05). The hair follicle density of the winter coat was not influenced by the dietary protein levels and Met supplementation (p > 0.05). Low-protein diets content led to a reduction of hair follicle developing to next phase. It was documented that 24% crude protein of DM with Met supplementation during growing-furring period was sufficient for minks to express their genetic capacity to develop hair follicles and achieve the prime fur characteristics. Overall this study demonstrated that hair growth and hair properties in pelts are very dependent on the dietary protein and Met supply in the growing-furring period of minks.

Comparative proteome analysis of glutenin synthesis and accumulation in developing grains between superior and poor quality bread wheat cultivars.

BACKGROUND: Wheat glutenins are the major determinants of wheat quality. In this study, grains at the development stage from three wheat cultivars (Jimai 20, Jin 411 and Zhoumai 16) with different bread-making quality were harvested based on thermal times from 150 °C(d) to 750 °C(d) , and were used to investigate glutenin accumulation patterns and their relationships with wheat quality. RESULTS: High and low molecular weight glutenin subunits (HMW-GSs and LMW-GSs) were synthesised concurrently. No obvious correlations between HMW/LMW glutenin ratios and dough property were observed. Accumulation levels of HMW-GSs and LMW-GSs as well as 1Bx13 + 1By16 and 1Dx4 + 1Dy12 subunits were higher in superior gluten quality cultivar Jimain 20 than in poor quality cultivar Jing 411 and Zhoumai 16. According to the results of two-dimensional gel electrophoresis, six types of accumulation patterns in LMW-GSs were identified and classified. The possible relationships between individual LMW-GSs and gluten quality were established. CONCLUSION: The high accumulation level of HMW-GSs and LMW-GSs as well as 1Bx13 + 1By16 and 1Dx4 + 1Dy12 subunits contributed to the superior gluten quality of Jimai 20. Two highly expressed and 16 specifically expressed LMW glutenin subunits in Jimain 20 had positive effects on dough quality, while 17 specifically expressed subunits in Zhoumai 16 and Jing 411 appeared to have negative effects on gluten quality.

Dietary protein quality and quantity affect lactational responses to corn distillers grains: a meta-analysis.

Diet fermentability influences lactational responses to feeding corn distillers grains (CDG) to dairy cows. However, some measures of diet fermentability are inherently related to the concentration and characteristics of corn-based ingredients in the ration. Corn-based feeds have poor protein quality, unable to meet the essential AA requirements of lactating cows. We conducted a meta-analysis of treatment means (n=44) from the scientific literature to evaluate responses in milk yield (MY) and milk true protein concentration and yield to dietary CDG. The test variable was the difference in response between the CDG diet mean and the control diet mean (0% CDG) within experiment. Fixed variables were CDG concentration of the diet [% of dietary dry matter (DM)] and crude protein (CP) concentration and fractions of CP based on origin (corn-based versus non-corn-based feeds) of control and CDG diets. Diets with CDG ranged from 4 to 42% CDG, DM basis. Non-corn-based dietary CP averaged 6.3±3.32% of total DM. Milk yield and milk true protein yield responses to added CDG were maximized when approximately 8.5% of the total dietary DM was non-corn-based CP. Milk yield response peaked for higher-producing cows (>30.0 kg MY/cow per day) at 4.3% dietary corn-based CP, but decreased linearly for lower-producing cows (<30.0 kg MY/cow per day) as corn-based dietary CP increased. Milk true protein yield response decreased as corn-based dietary CP concentration increased but milk true protein concentration response was not decreased when CDG diets had more than 6.5% dietary non-corn-based CP. Overall, 8.5% dietary non-corn-based CP was necessary in lactation diets to maximize lactational responses to dietary CDG. The necessity of dietary non-corn-based CP to maximize milk and milk protein yields limits the amount of dietary corn-based CP, including that from CDG, which can be included in rations without overfeeding N.

Protein Amount, Quality, and Physical Activity.

Diet composition determines the risk of obesity, cardiovascular disease, malignant tumors, and type 2 diabetes mellitus [...].

Adjusting for protein quality by food source may affect nutrient density metrics.

Methods to assess nutrient density of foods, commonly known as nutrient profiling (NP), typically include protein as a component. In this study, the goal was to apply a correction for protein quality by food source to selected NP algorithms. Analyses of 378 component foods of the Fred Hutch food frequency questionnaire showed that animal-source foods (ie, meat, eggs, and dairy) along with some soy products and nuts were the only foods that provided > 20% of the daily value (DV) of protein per 100 g or per 100 kcal. Most beans, pulses, legumes, grains, and vegetables provided <10% DV of protein per 100 g or per 100 kcal. Adjusting for protein quality using a simplified Protein Digestibility Corrected Amino Acid Score (PDCAAS) had consequences for point-based NP models (namely, Nutri-Score) and for continuous nutrient density scores (namely, Nutrient Rich Foods). Quantitative methods that use protein content to capture nutrient density may require a protein-quality adjustment, especially when adapted for use in low- and middle-income countries where protein quality is an issue of public health concern.

Dietary Protein Requirement Threshold and Micronutrients Profile in Healthy Older Women Based on Relative Skeletal Muscle Mass.

Although multiple nutrients have shown protective effects with regard to preserving muscle function, the recommended amount of dietary protein and other nutrients profile on older adults for maintenance of high muscle mass is still debatable. The aims of this paper were to: (1) identify dietary differences between older women with low and high relative skeletal muscle mass, and (2) identify the minimal dietary protein intake associated with high relative skeletal muscle mass and test the threshold ability to determine an association with skeletal muscle phenotypes. Older women (n = 281; 70 ± 7 years, 65 ± 14 kg), with both low and high relative skeletal muscle mass groups, completed a food questionnaire. Skeletal muscle mass, fat-free mass (FFM), biceps brachii thickness, vastus lateralis anatomical cross-sectional area (VLACSA), handgrip strength (HGS), maximum elbow flexion torque (MVCEF), maximum knee extension torque (MVCKE), muscle quality (HGS/Body mass), and fat mass were measured. Older women with low relative skeletal muscle mass had a lower daily intake of protein, iodine, polyunsaturated fatty acid (PUFA), Vit E, manganese, milk, fish, nuts and seeds (p < 0.05) compared to women with high relative skeletal muscle mass. The minimum required dietary protein intake for high relative skeletal muscle mass was 1.17 g/kg body mass/day (g/kg/d) (sensitivity: 0.68; specificity: 0.62). Women consuming ≥1.17 g/kg/d had a lower BMI (B = -3.9, p < 0.001) and fat mass (B = -7.8, p < 0.001), and a higher muscle quality (B = 0.06, p < 0.001). The data indicate that to maintain muscle mass and function, older women should consume ≥1.17 g/kg/d dietary protein, through a varied diet including milk, fish and nuts that also contain polyunsaturated fatty acid (PUFA) and micronutrients such as iodine, Vit E and manganese.

Nutritional composition, assessed by chemical analyses, of prepared foods available for primary-school children: a comparison of public and private schools.

OBJECTIVE: To assess the nutritional quality of prepared foods available to primary-school children. DESIGN: Prepared foods available in a public and private school were sampled daily for 4 weeks (a total of forty-five samples) and chemically analysed for protein, fat, carbohydrate, iron, salt and sodium. The results were compared to the nutritional standards for children aged 7-10 years. SETTING: Alfenas, south-eastern Brazil. RESULTS: The concentration of protein, lipid, iron and sodium and the energy values of the foods at the private school were significantly higher than those at the public school. No differences were seen in the carbohydrate and salt values. The range of macronutrients was more balanced at the public school in relation to fat and protein. Foods at the private school were, in general, energy-dense. At both the public and private school, they provided the minimum energy and iron. Salt content was over twice the maximum amount, and that for sodium was over three times the amount, in both the public and private school. CONCLUSIONS: Overall, foods prepared at the public school were better nutritional quality than those at the private school and those offered in public schools in some developed countries. This finding can probably be explained by the fact that a nutritionist, as required by law, was responsible for planning the menus at the public school. However, corrective action is needed to adjust for the wide variability in energy and nutrient content during weekdays and in the sodium content of prepared foods available in both the public and private school.

Short report: Relationship between quality protein, lean mass and bone health.

BACKGROUND: Quality protein intake, and distribution of that protein, could play an important role with lean mass (LM), bone mineral density (BMD) and bone mineral content (BMC). Research has demonstrated that muscle protein synthesis is maximally stimulated at approximately 10 g of essential amino acids (EAA)/meal. This study sought to determine the relationship between the amount of quality protein consumed and the amount of times the approximately 10 g EAA threshold was reached at a meal, with respect to LM, BMD and BMC. METHODS: Twenty-seven subjects participated in this study. EAA intake was determined from a 3-day food record, and amino acid profiling was determined using a computer program (USDA Database, release 22). LM, BMD and BMC were measured using dual-energy X-ray absorptiometry. Quality protein was defined as the ratio of EAA to total dietary protein. Data were analyzed using Pearson partial coefficient correlations, controlling for body mass, with an α-level of 0.05. RESULTS: Quality protein consumed in a 24-hour period and the amount of times reaching the EAA threshold per day was positively associated with LM, BMD and BMC, and had an inverse relationship with body fat percentage. CONCLUSION: Both quality protein intake and frequency are positively associated with favorable body composition and bone health.