Role of Amino Acids in Blood Glucose Changes in Young Adults Consuming Cereal with Milks Varying in Casein and Whey Concentrations and Their Ratio

Abstract

Background Increasing the total protein content and reducing the casein to whey ratio in milks consumed with breakfast cereal reduce postprandial blood glucose (BG). Objectives We aimed to explore associations between plasma amino acids (AAs), BG, and glucoregulatory hormones. Methods In this repeated-measures design, 12 healthy adults consumed cereal (58 g) and milks (250 mL) with 3.1 wt% or high 9.3 wt% protein concentrations and with casein to whey ratios of either 80:20 or 40:60. Blood was collected at 0, 30, 60, 120, 140, 170, and 200 min for measurement of the primary outcome, BG, and for the exploratory outcomes such as plasma AA, gastric emptying, insulin (INS), and glucoregulatory hormones. Measures were made prior to and after an ad libitum lunch at 120 min. Exploratory correlations were conducted to determine associations between outcomes. Results Pre-lunch plasma AA groups [total (TAA), essential (EAA), BCAA, and nonessential (NEAA)] were higher after 9.3 wt% than 3.1 wt% milks by 12.7%, 21.4%, 20.9%, and 7.6%, respectively (P ≤ 0.05), while post-lunch AA groups were higher by 10.9%, 19.8%, 18.8%, and 6.0%, respectively (P ≤ 0.05). Except for NEAA, pre-lunch AAs were higher after 40:60 than 80:20 ratio milks by 4.5%, 8.3%, and 9.3% (P ≤ 0.05). When pooled by all treatments, pre-lunch AA groups associated negatively with BG (r/ρ ≥ −0.45, P ≤ 0.05), but post-lunch only TAA and NEAA correlated (r ≥ −0.37, P < 0.05). Pre-lunch BG was inversely associated with Leu, Ile, Lys, Met, Thr, Cys-Cys, Asn, and Gln (r/ρ ≥ −0.46, P ≤ 0.05), but post-lunch, only with Thr, Ala, and Gly (r ≥ −0.50, P ≤ 0.05). Pre-lunch associations between AA groups and INS were not found. Conclusions Protein concentration and the ratio of casein to whey in milks consumed at breakfast with cereal affect plasma AA concentrations and their associations with decreased BG. The decrease in BG could be explained by INS-independent mechanisms. This trial was registered at www.clinicaltrials.gov as NCT02471092.

Glycemic response of honey and dates consumption

“…38 Adopting strategical dietary plan is undoubtedly support in GI control; for instance, dietary fiber content and with less sensitive affect the amount of protein content in food may affect the value of GI via the various mechanism of action (gastric emptying, starch enzymatic digestion reduction, and decreasing the mucosa absorption rate). 17,39 However, date and honey are low in fiber and protein, especially honey. 4,7 Furthermore, the gender effect and association to BG response for the tested foods in the study shows that females and males responses were not significantly (P>0.05) different if compared time by time as shown in Figure 2.…”

“…1,2 Honey is a natural sugary product produced by honey bees (Apis mellifera). 3 Natural honey is a sticky and viscous solution with an estimated percentage content of 80-85 carbohydrates that is mainly fructose (36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50) and glucose (28)(29)(30)(31)(32)(33)(34)(35)(36), and the remaining are 15-17 water, 0.1-0.4 protein, and 0.2 ash. 4 Besides, date palm (Phoenix dactylifera L.) is one of the oldest fruit source known in the dry and semidry areas.…”