Effect of whey protein on blood pressure in pre‐ and mildly hypertensive adults: A randomized controlled study

Abstract

In China, the frequency of mild hypertension cases remains prevalently high. Meanwhile, diets containing functional ingredients that control blood pressure have received considerable attention. In this randomized, controlled intervention study, 65 participants were randomly assigned to consume 30 g of whey protein or maltodextrin daily for 12 weeks. Blood pressure, body composition, biochemical analysis in plasma, and flow‐mediated dilation (FMD), an index for evaluating endothelial function, were measured. Finally, 54 participants (27 participants in each group) completed the study. At the end of the intervention, the average systolic blood pressure (SBP) was 129.5 ± 7.7 mmHg in the control group and 128.2 ± 6.9 mmHg in the whey protein group ( p = 0.052). In the overweight and obese participants, the SBP was significantly lower in the whey protein group than in the control group (126.5 ± 6.9 mmHg vs. 128.8 ± 7.4 mmHg, p = 0.033), and body fat, fat percentage, and waist circumference significantly decreased in the whey protein group ( p = 0.010, 0.016, 0.019, respectively). No difference was observed between the control and whey protein groups with regard to the changes in plasma lipids, inflammatory cytokines, antioxidative indexes, endothelium‐1, nitric oxide, angiotensin II, and angiotensin‐converting enzyme. The increase in FMD was significantly higher in the whey protein group than in the control group (5.2% vs. 0.3%, p = 0.040). In conclusion, whey protein significantly decreased SBP in pre‐ and mildly hypertensive adults, who are also overweight and obese. Whey protein also improved endothelial function. The lowering effect of blood pressure was probably related to body fat loss in these participants.

Effects of whey protein on glycemic control and serum lipoproteins in patients with metabolic syndrome and related conditions: a systematic review and meta-analysis of randomized controlled clinical trials

“…Characteristics of included studies are summarized in Table 1 . Participants had chronic diseases like HTN [ 22 , 28 , 31 , 40 ] and T2DM [ 33 , 36 , 38 ] in some studies. The intervention period varied from 4 weeks to 24 weeks.…”

“…In 5 studies, a dosage of ≤20 mg/d was used [ 9 , 23 , 28 , 29 , 32 ]. Six trials used whey protein in dosages between 20 and ≤ 40 mg/d [ 25 , 30 , 33 , 36 , 38 , 40 ]. Five other studies used it at a daily dose between 40 and 60 mg [ 10 , 26 , 31 , 35 , 41 ].…”

“…Three studies did not report the amount of whey protein used in their interventions [ 22 , 24 , 37 ]. Eight studies used isolate [ 10 , 24 , 27 , 28 , 31 , 37 – 39 ] and 4 studies used concentrate whey protein [ 33 , 34 , 36 , 40 ]. Combined isolate plus concentrate [ 30 ], hydrolysate [ 41 ], and intact [ 23 ] whey protein was reported each in one trial.…”

“… Mohammadi-Sartang et al [ 9 ] 2018 44/43 Iran/ Overweight/obese subjects with metabolic syndrome (BMI: 25–34.9) on energy reduction BMI: 30.1 ± 2.6, 30.8 ± 2.2 Both 17/27, 17/26 No Fortified yogurt containing 10 g/d WP, 1000 mg calcium, and 1000 IU vitamin D NR Placebo product: low-fat conventional yogurt 10 20–65 FPG Insulin HOMA-IR TG TC HDL-C LDL-C HOMA-IR and TG significantly decreased and HDL-C significantly increased in both groups and between group changes were significant compared control. Yang et al [ 40 ] (a) 2019 12/12 China/ Overweight subjects with prehypertension and mild HTN BMI: NR Both NR No 30 g/d WP powder concentrate CHO supplementation: 30 g/d maltodextrin powder 12 ≥18 FPG TG TC HDL-C LDL-C No significant changes compared control. Yang et al [ 40 ] (b) 2019 15/15 China/ Normal weight subjects with prehypertension and mild HTN BMI: NR Both NR No 30 g/d WP powder concentrate CHO supplementation: 30 g/d maltodextrin powder 12 ≥18 FPG TG TC HDL-C LDL-C No significant change compared control.…”

“…Among studies analyzed in this meta-analysis concerning the significance of between group changes for glycemic parameters, significant decrease of FPG was reported in one study [ 33 ], while it was unaffected by treatment in 12 studies [ 9 , 22 , 24 , 27 , 30 – 32 , 34 , 35 , 38 , 40 , 41 ], and it was increased in two studies [ 29 , 39 ]. A significant decrease of insulin was shown in one study [ 9 ], while it was unaffected by treatment in 9 studies [ 22 , 24 , 29 – 32 , 34 , 35 , 38 ].…”