Plasma amino acid response to single test meals in humans

Abstract

The postprandial plasma amino acid response to test meals containing different amino acid mixtures was analysed in six young adults. The amount of amino acids given in each test meal was equivalent with 3.5 g of nitrogen. Each test meal also contained a large amount of carbohydrate (mainly as wheat starch). Five different amino acid mixtures were used, and the effects on the plasma amino acid response of different dietary levels of lysine, isoleucine and methionine were studied in detail. The plasma amino acid responses were evaluated both by a modified Longenecker and Hause procedure (PAA ratios) and by the procedure proposed by Graham and Placko (percentage changes in the postprandial essential amino acid molar ratios). The plasma amino acid response of lysine was found to be less sensitive to reductions in the dietary supply than the isoleucine and methionine responses evaluated by these procedures. The influence of altered levels of dietary supply on the postprandial plasma concentrations of isoleucine and methionine seemed to be specifically great at the intake levels where these essential amino acids become limiting for protein utilization according to the amino acid score of the test mixtures. The nutritional significance of the postprandial pattern and level of essential amino acids is discussed on basis of the present results. Experimental conditions and evaluation models are examined with regard to the use of single-meal plasma amino acid responses to assess the protein quality of human diets.

Lysine fortification reduces anxiety and lessens stress in family members in economically weak communities in Northwest Syria

“…The average total daily intake of protein in males was 70.1 Ϯ 2.7 g, of which Ͼ65% was of cereal origin. Only dietary intake was used as a measure of lysine adequacy because plasma lysine is a poor indicator of dietary changes (14). The diet of the studied communities was characterized by only marginal total protein deficiency; thus, we were able to separate the probable effects of lysine inadequacy from those of general protein malnutrition.…”

Effect of lysine supplementation on hypertensive men and women in selected peri-urban community in Ghana

“…For the 24 h recall, the participants were asked to mention all the foods they had consumed in the past 24 h prior to the interview. With the help of food models they were made to estimate the quantities or portions they consumed and with the help of food composition tables, their nutrient intake was estimated Blood plasma lysine is known to be poor indicator of dietary lysine status thus only dietary information was used to determine lysine levels [8]. Dietary data were converted into nutrient content using Ghanaian Food Composition Tables and [9] supplemented by US Department of Agriculture Table [10], owing to absence of amino acid data in the 'Ghanaian Food Composition Tables'.…”