Mycoprotein reduces energy intake and postprandial insulin release without altering glucagon-like peptide-1 and peptide tyrosine-tyrosine concentrations in healthy overweight and obese adults: a randomised-controlled trial

Abstract

Dietary mycoprotein decreases energy intake in lean individuals. The effects in overweight individuals are unclear, and the mechanisms remain to be elucidated. This study aimed to investigate the effect of mycoprotein on energy intake, appetite regulation, and the metabolic phenotype in overweight and obese volunteers. In two randomised-controlled trials, fifty-five volunteers (age: 31 (95 % CI 27, 35) years), BMI: 28·0 (95 % CI 27·3, 28·7) kg/m2) consumed a test meal containing low (44 g), medium (88 g) or high (132 g) mycoprotein or isoenergetic chicken meals. Visual analogue scales and blood samples were collected to measure appetite, glucose, insulin, peptide tyrosine-tyrosine (PYY) and glucagon-like peptide-1 (GLP-1). Ad libitum energy intake was assessed after 3 h in part A (n 36). Gastric emptying by the paracetamol method, resting energy expenditure and substrate oxidation were recorded in part B (n 14). Metabonomics was used to compare plasma and urine samples in response to the test meals. Mycoprotein reduced energy intake by 10 % (280 kJ (67 kcal)) compared with chicken at the high content (P=0·009). All mycoprotein meals reduced insulin concentrations compared with chicken (incremental AUClow (IAUClow): -8 %, IAUCmedium: -12 %, IAUChigh: -21 %, P=0·004). There was no significant difference in glucose, PYY, GLP-1, gastric emptying rate and energy expenditure. Following chicken intake, paracetamol-glucuronide was positively associated with fullness. After mycoprotein, creatinine and the deamination product of isoleucine, α-keto-β-methyl-N-valerate, were inversely related to fullness, whereas the ketone body, β-hydroxybutyrate, was positively associated. In conclusion, mycoprotein reduces energy intake and insulin release in overweight volunteers. The mechanism does not involve changes in PYY and GLP-1. The metabonomics analysis may bring new understanding to the appetite regulatory properties of food.

Keywords: Appetite hormones; Energy intake; GAA guanidinoacetic acid; GI gastrointestinal; GLP-1 glucagon-like peptide-1; Gastric emptying; IAUC incremental AUC; Metabonomics; Mycoprotein; Obesity; Overweight; PYY peptide tyrosine-tyrosine; REE resting energy expenditure; T2DM type 2 diabetes mellitus.

Figures

Fig. 1

Protocol of the study visits. Participants arrived at 08.30 hours in a fasted state. The test meal consisted of a standardised mycoprotein or chicken risotto. The ad libitum meal was consumed 180 min after the test meal until the participant was fully satisfied. Paracetamol was given in part B as a surrogate measurement of gastric emptying. VAS, visual analogue scale.

Fig. 2

Fullness ratings over time at low (a), medium (b) and high (c) protein contents following the consumption of mycoprotein and chicken. Values are means, with standard errors. * P≤0·05 on repeated-measures linear mixed model and post hoc comparisons with Bonferroni’s correction. , Low chicken; , low mycoprotein; , medium chicken; , medium mycoprotein; , high chicken; , high mycoprotein.

Fig. 3

Energy intake at ad libitum meal (a) and during the following 24 h (b). Values are means, with standard errors represented by bar charts. * P≤0·05, ** P≤0·01 difference between mycoprotein and chicken analysed with repeated-measures linear mixed model and post hoc comparisons with Bonferroni’s correction. , , , Chicken; , , , mycoprotein; , low protein; , medium protein; , high protein.

Fig. 4

Plasma concentrations of glucagon-like peptide-1 (GLP-1) and peptide tyrosine-tyrosine (PYY) following the consumption of mycoprotein and chicken. Values are means, with standard errors. , High chicken; , high mycoprotein.

Fig. 5

Plasma glucose and serum insulin concentrations at low, medium and high-protein contents and insulin sensitivity following the consumption of mycoprotein and chicken. (a–c) Plasma glucose concentrations at low (a), medium (b) and high (c) protein contents. (d–f) Serum insulin concentrations at low (d), medium (e) and high (f) protein contents. * P≤0·05, ** P≤0·01, *** P≤0·001 difference between mycoprotein and chicken analysed by repeated-measures linear mixed model and post hoc comparisons at each time point with Bonferroni’s correction. (g–i) Matsuda (g), Insulinogenic (h) and Disposition (i) indices. Values are means, with standard errors and log-transformed before analysis. * P≤0·05 difference between mycoprotein and chicken analysed by repeated-measures linear mixed model and post hoc comparisons with Bonferroni’s correction. , Low chicken; , low mycoprotein; , medium chicken; , medium mycoprotein; , high chicken; , high mycoprotein; , , , chicken; , , , mycoprotein; , low protein; , medium protein; , high protein.

Fig. 6

Appetite ratings following the consumption of mycoprotein and chicken: hunger (a), nausea (b), desire to eat (c), prospective food intake (d), fullness (e) and IAUC for all appetite ratings (f). Values are means, with standard errors. IAUC, incremental AUC. , Chicken; , mycoprotein.

Fig. 7

Serum paracetamol concentrations (a) and gastric emptying rate (b) following the consumption of mycoprotein and chicken. (a) Values are means, with standard errors. (b) Values are mean gastric emptying percentages for all participants with a non-linear fit of the curve. , Chicken; , mycoprotein; , non-linear fit (chicken); , non-linear fit (mycoprotein).

Fig. 8

Energy expenditure (per kg lean mass) (a), RER (b), carbohydrate oxidation (c), fat oxidation (d) following the consumption of mycoprotein and chicken. Values are means, with standard errors. CHO, carbohydrate. , Chicken; , mycoprotein.

Fig. 9

Orthogonal projection to latent structures-discriminant analysis models comparing the urinary metabolic profiles of volunteers following chicken and mycoprotein intake (a) and the plasma metabolic profiles 30 v. 180 min after mycoprotein consumption (b). Colour corresponds to the correlation of the metabolites to class discrimination ((a) mycoprotein v. chicken; (b) 30 v. 180 min post-mycoprotein consumption). Colour indicates the strength of correlation. N-acetylcarnitine, carnitine and anserine increase following chicken intake. Guanidinoacetic acid and unknown (2·48) increase following mycoprotein intake. Valine, isoleucine, leucine, and N-acetyl-glycoprotein increase at 180 min. Glucose decreases at 180 min. ppm, Parts per million.

Fig. 10

Orthogonal projection to latent structure models showing metabolic variation associated with fullness following mycoprotein (a) and chicken (b) intake. (a) Colour indicates the correlation of the metabolites with fullness. After mycoprotein intake, creatinine and the deamination product of isoleucine, α-keto-β-methyl-N-valerate, were inversely related to fullness and β-hydroxybutyrate was positively associated. (b) Significant associations are shown in red. After chicken intake, paracetamol-glucuronide was positively associated with fullness and creatinine was negatively associated.