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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., (© The Author(s) 2020. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The aging process is frequently characterized by an involuntary loss of muscle (sarcopenia) and bone (osteoporosis) mass. Both chronic diseases are associated with decreased metabolic rate, increased risk of falls/fracture, and, as a result, increased morbidity and loss of independence in the elderly. The quality and quantity of protein intake affects bone and muscle mass in several ways and there is evidence that increased essential amino acid or protein availability can enhance muscle protein synthesis and anabolism, as well as improve bone homeostasis in older subjects. A thorough evaluation of renal function is important, since renal function decreases with age. Finally, protein and calcium intake should be considered in the prevention or treatment of the chronic diseases osteoporosis and sarcopenia., (© 2010 International Life Sciences Institute.)

The purpose of this study was to determine whether the quantity and quality of dietary protein affected the polysome profile of the brain in aged rats. Two experiments were done on three groups of aged rats (30 wk) given the diets containing 20% casein, 5% casein, or 0% casein (experiment 1), and 20% casein, 20% gluten, or 20% gelatin (experiment 2) for 10 d. The aggregation in brain ribosomes declined with a decrease of quantity and quality of dietary protein except in the hippocampus. The RNA concentration (mg RNA/g protein) did not differ among the three groups varying the dietary protein in any brain regions. The results suggest that the higher quantity and quality of dietary protein improves the polysome profile in the brain of aged rats, and that the polysome profile is at least partly related to the mechanism by which the dietary protein affects brain protein synthesis in aged rats.

In response to US dietary guidelines and health goals, the food industry has introduced a variety of innovative food products designed to help the American public lower its fat intake. The physical characteristics and safety considerations of these products are reviewed, as well as their association with chronic disease prevention.

The effect of the quality of dietary protein on the post-initiation development of aflatoxin B1-initiated putatively preneoplastic foci in Fischer 344 rat liver was compared with the effect of the quantity of dietary protein. Feeding wheat gluten, a low-quality protein, during the postinitiation period (between the end of aflatoxin B1 dosing and the death of the rats) inhibited the development of gamma-glutamyltransferase-positive foci when compared with that in animals fed high-quality protein (casein) diets during the same period. Lysine supplementation of wheat gluten during the postinitiation period enhanced the gamma-glutamyltransferase-positive response to a level comparable with that of the high-quality protein. These results suggest that one can inhibit the development of foci either by decreasing the quantity of protein intake and holding the quality of the protein constant or by decreasing the quality and holding the quantity constant.