Incorporating Milk Protein Isolate into an Energy-Restricted Western-Style Eating Pattern Augments Improvements in Blood Pressure and Triglycerides, but Not Body Composition Changes in Adults Classified as Overweight or Obese: A Randomized Controlled Trial

Abstract

Unhealthy Western-style eating patterns (WSEP) predominate, adversely affecting health. Resistance to improving dietary patterns prompts interest to incorporate a potentially health-promoting ingredient into typical WSEP foods and beverages. We assessed the effect of incorporating isocalorically matched carbohydrates versus milk protein isolate (MPI) into a WSEP on weight loss-induced changes in cardiometabolic health and body composition. In a randomized, double-blind, parallel-design study, 44 participants (age 52 ± 1 years, body mass index (BMI) 31.4 ± 0.5 kg/m2, mean ± standard error) consumed a weight maintenance WSEP (0.8 g total protein/kg/day) for 3 weeks (baseline). After, participants consumed an energy-restricted (750 kcal/day below estimated requirement) WSEP for 16 weeks, randomly assigned to contain either an additional 0.7 g carbohydrate/kg/d (CON: n = 23, 0.8 g total protein/kg/day) or 0.7 g protein/kg/d from MPI (MPI: n = 21, 1.5 g total protein/kg/day) incorporated into foods and beverages. Compared to CON, the MPI favored reductions in average 24 h and sleeping systolic and diastolic blood pressures (BP), waking hours systolic BP, and fasting plasma triglyceride concentrations. Reductions in fasting plasma insulin, glucose, total cholesterol, and low-density lipoprotein cholesterol concentrations were not different between groups. Among all participants, whole body mass, lean mass, fat mass, and thigh muscle area, each decreased over time. For adults finding it difficult to deviate from a WSEP, replacing a portion of their carbohydrate with foods and beverages containing MPI may be an effective dietary strategy to reduce BP after weight loss.

Effects of supplementation with milk protein on glycemic parameters: a GRADE-assessed systematic review and dose–response meta-analysis

“…The sample sizes ranged from 16 to 171 participants. Twenty RCTs [ 52 – 58 , 62 , 63 , 66 , 70 , 71 , 74 – 76 , 79 , 80 , 82 , 83 , 87 ] used a mixed-sex sample, while seven and nine studies had a women-only sample [ 64 , 68 , 69 , 77 , 78 , 81 , 86 ] or a men-only sample [ 59 – 61 , 65 , 67 , 72 , 73 , 84 , 85 ], respectively.…”

“…The trials enrolled patients with pre-or mild hypertension [ 52 , 79 ], amyotrophic lateral sclerosis (ALS) [ 55 ], metabolic syndrome [ 58 ], after bariatric surgery (> 24 months) [ 69 ], hypoalbuminemia on peritoneal dialysis [ 70 ], T2DM [ 73 , 76 ], and sarcopenic elderly men [ 67 ]. In addition, the RCTs were carried out among participants with overweight or obesity [ 53 , 54 , 56 , 60 , 61 , 64 – 66 , 75 , 78 , 80 , 84 ], visceral fat [ 57 ], or abdominal obesity [ 83 ], and post-menopausal women [ 68 ] with overweight [ 86 ] or obesity [ 81 ]. The studies also included older women with sarcopenic obesity [ 77 ], futsal players [ 85 ], nursing home residents [ 62 ], elderly adults [ 63 , 71 , 82 ], and healthy individuals [ 59 , 72 , 74 ] with mildly elevated blood pressure (BP) [ 36 ].…”

“…The RCTs were performed in Germany [ 52 , 58 ], Australia [ 53 , 56 , 86 ], Netherlands [ 54 ], Brazil [ 55 , 69 , 77 , 78 ], Japan [ 57 ], Portugal [ 85 ], Sweden [ 59 , 84 ], and Iran [ 60 , 61 , 65 , 81 ]. The settings of studies were also Finland [ 62 ], the Czech Republic [ 63 ], the United States(US) [ 64 , 66 , 68 , 72 , 74 , 80 , 82 ], the United Kingdom(UK) [ 87 ], Canada [ 67 ], Israel [ 70 ], Norway [ 71 ], New Zealand [ 73 ], Denmark [ 75 , 83 ], Italy [ 76 ], and China [ 79 ]. The length of the trials was between 3 and 72 weeks and the doses of MP, WP, or CP supplements ranged from 3.5 to 90 g per day.…”

“…The effect of MP administration on serum fasting insulin values was evaluated in 20 RCTs [ 52 – 54 , 57 – 59 , 62 , 64 , 66 , 67 , 75 – 78 , 80 , 81 , 83 , 84 , 86 , 87 ] that involved 1100 participants (603 cases and 613 controls). A pooled analysis of 24 effect sizes indicated that the level of serum fasting insulin was considerably lower in the MP-treated group than in the control group (WMD: -1.06 uU/mL, 95% CI: -1.76, -0.36; P = 0.003).…”

“…Seventeen trials [ 52 , 54 , 58 , 59 , 64 , 66 , 68 , 69 , 73 , 76 – 78 , 80 , 81 , 83 , 84 , 87 ] with 20 effect sizes and 940 participants revealed the impact of MP supplementation on HOMA-IR values. The meta-analysis displayed that the mean value of HOMA-IR was considerably lower in the experimental group than in the controls (WMD: -0.27, 95% CI: -0.40, -0.14; P < 0.…”