Evaluation of a novel food composition database that includes glutamine and other amino acids derived from gene sequencing data

Abstract

Objectives To determine the content of glutamine in major food proteins. Subjects/Methods We used a validated 131-food item food frequency questionnaire (FFQ) to identify the foods that contributed the most to protein intake among 70 356 women in the Nurses’ Health Study (NHS, 1984). The content of glutamine and other amino acids in foods was calculated based on protein fractions generated from gene sequencing methods (Swiss Institute of Bioinformatics) and compared with data from conventional (USDA) and modified biochemical (Khun) methods. Pearson correlation coefficients were used to compare the participants’ dietary intakes of amino acids by sequencing and USDA methods. Results The glutamine content varied from 0.01 to to 9.49 g/100 g of food and contributed from 1 to to 33% of total protein for all FFQ foods with protein. When comparing the sequencing and Kuhn’s methods, the proportion of glutamine in meat was 4.8 vs 4.4%. Among NHS participants, mean glutamine intake was 6.84 (s.d.=2.19) g/day and correlation coefficients for amino acid between intakes assessed by sequencing and USDA methods ranged from 0.94 to 0.99 for absolute intake, −0.08 to 0.90 after adjusting for 100 g of protein, and 0.88 to 0.99 after adjusting for 1000 kcal. The between-person coefficient of variation of energy-adjusted intake of glutamine was 16%. Conclusions These data suggest that (1) glutamine content can be estimated from gene sequencing methods and (2) there is a reasonably wide variation in energy-adjusted glutamine intake, allowing for exploration of glutamine consumption and disease.

Effects of oral glutamine during abdominal radiotherapy on chronic radiation enteritis: A randomized controlled trial

“…A whole protein was considered a suitable, although not perfect, comparator. It should be noted that Gln is present in all protein foods, although represents <10 % of the amino acid content of casein [23]. The appropriate dose of Gln for each clinical condition is also unclear.…”

Where the Pendulum of Knowledge Stands Now: Is Circulating Albumin a Marker of Inflammation or of Malnutrition? How to Manage Hypoalbuminemia by Nutrition?

“…Thus, if nitrogen balance is used as the gold standard to certify sufficient quality of nitrogen intake, as we have observeded in animals [8] and paradoxically also in extreme human setting [9], [10] we may observe either a normalized nitrogen balance and the maintenance of clinical evidences of malnutrition comprehensive of unsuccessful treatment of hypoalbuminemia, unless we used very large doses of EAA as a major source of nitrogen. While nitrogen balance is used as a main standard to measure nitrogen intake, while in our opinion it certifies both dimensions of catabolic efflux of NEAA from wasting muscles and the excess nitrogen supplied by food to the body and potentially unsuitable to be fully used for maintaining adequate protein syntheses due to the reduced ratio (always < 0,9, but in beef, according cuts, may be near 0,7) among EAA and NEAA provided by food proteins [11]. and the ratios EAA/NEAA in animals have recently been found to correlate with a reduced life span [8].…”

Food and Drug Administration Approval of Glutamine for Sickle Cell Disease: Success and Precautions in Glutamine Research

“…The content of gln and other amino acids has recently been determined on the basis of genetic maps that are available for various food proteins 17 , 36 . The calculated quantity of gln was then compared with the U.S. Department of Agriculture's laboratory measurement to validate these calculations.…”

“…With this amino acid directory based on genetic information, the diets of 70,356 women aged 38–63 years who reported a yearly daily food intake for 18 years were analyzed. On study entry, the women were free of cardiovascular disease, cancer, and diabetes 36 …”