The effects of whey protein on blood pressure: A systematic review and dose-response meta-analysis of randomized controlled trials.

2023-09
Nutrition, metabolism, and cardiovascular diseases : NMCD 33(9)
- Mahdi Vajdi
- Vali Musazadeh
- Mohammad Zareei
- Shaghayegh Adeli
- Arash Karimi
- Ali Hojjati
- Melika Darzi
- Hamed Shoorei
- Mahdieh Abbasalizad Farhangi

PubMed: 37419751
DOI: 10.1016/j.numecd.2023.05.025

Study Design

Type: Meta-Analysis
Sample size: n = 177
Methods: systematic review and dose-response meta-analysis of 18 studies with 1,177 subjects

Aims

This systematic review and dose-response meta-analysis was conducted to summarize data from available clinical trials on the effects of whey protein (WP) supplementation on blood pressure (BP) in adults.

Data synthesis

A comprehensive literature search was conducted in the electronic databases PubMed, Web of Science, ProQuest, Embase, and SCOPUS from inception to October 2022. Weighted mean differences (WMD) and 95% confidence intervals (CI) were calculated to assess pooled effect sizes. Heterogeneity between studies was assessed using the Cochran's Q test and I². Subgroup analysis was performed to assess potential sources of heterogeneity. The dose-response relationship was assessed using fractional polynomial modeling. Of the 2,840 records, 18 studies with 1,177 subjects were included. Pooled analysis showed that whey protein supplementation resulted in a significant reduction in systolic blood pressure (WMD: -1.54 mmHg; 95% CI: -2.85 to -0.23, p = 0.021), with significant heterogeneity between studies (I² = 64.2%, p < 0.001), but not for diastolic blood pressure (DBP) (WMD: -0.27 mmHg; 95% CI: -1.14, 0.59, p = 0.534) with high heterogeneity between studies (I² = 64.8%, p < 0.001). However, WP supplementation significantly reduced DBP at a dose of ˃30 g/day, in RCTs that used WP isolate powder for their intervention, in sample sizes ≤100, in studies with an intervention duration of ≤10 weeks, and in those studies that were conducted in patients with hypertension and had participants with a BMI of 25-30 kg/m².

Conclusion

This meta-analysis demonstrated that WP intake significantly reduced SBP levels. Further large-scale studies are needed to specify the exact mechanism, and optimal dosage of WP supplementation to obtain a beneficial effect on BP.

Research Insights

Whey Protein→Reduced Diastolic Blood Pressure
but not for diastolic blood pressure (DBP) (WMD: -0.27 mmHg; 95% CI: -1.14, 0.59, p = 0.534) with high heterogeneity between studies
Effect
Neutral
Effect size
Small
Whey Protein→Reduced Systolic Blood Pressure
Pooled analysis showed that whey protein supplementation resulted in a significant reduction in systolic blood pressure (WMD: -1.54 mmHg; 95% CI: -2.85 to -0.23, p = 0.021)
Effect
Beneficial
Effect size
Small