Writing in the journal Clinical Nutrition, European researchers reported findings from a meta-analysis of 21 randomized controlled trials investigating the protein’s effect on lowering systolic blood pressure (SBP), LDL cholesterol and total cholesterol levels.
“To our knowledge, this is the first systematic review and meta-analysis of RCTs that investigated the effect of whey protein supplementation on multiple markers of cardiometabolic health in adults,” they wrote.
Nutritional role
The prevalence of hypertension in adults over the age of 30 has doubled in the last three decades, while type 2 diabetes is estimated to impact more than 6,000 people per 100,000. Obesity, hypertension, insulin resistance and dyslipidemia are the factors that lead to diabetes and cardiovascular disease.
Dietary changes can influence a person’s cardiometabolic state and more evidence demonstrates dietary protein can reduce cardiovascular disease risk.
“The primary nutritional role of dietary protein is the provision of amino acids for the synthesis of new functional proteins, including skeletal muscle,” the researchers noted. “Specifically, whey protein as a by-product of cheese manufacturing and ‘high-quality’ protein source has been purported to improve markers of metabolic and cardiovascular health via multiple mechanisms linked with the increased delivery of bio-active peptides.”
Studies also indicate that whey protein can improve post-meal glycemic and insulin control. According to the research, this may be a result of enhanced β-cell function, which increases GLP-1 and glucose-dependent insulinotropic peptide (GIP) in adults who are middle-aged and have type 2 diabetes.
Study details
The researchers reported a 3-mmHg drop in SBP for individuals under the age of 50 who supplemented with whey protein. This calculated to a 6% reduction in cardiovascular disease risk for the cohort. The study suggested that this could be due to the increased bioavailability of bioactive peptides found in whey protein.
In the studies reviewed, participants experienced a 5 mg/dL reduction in LDL-cholesterol when whey protein use was combined with exercise. This equated to a 1.5 % reduction in all-cause mortality and 2.5 % risk reduction from coronary heart disease.
“Studies suggest that combining whey protein ingestion with exercise enhances the expression of LDL receptors, facilitating the clearance of LDL-cholesterol from the circulation,” the researchers noted. “Our observation of an ∼5 % reduction of LDL-cholesterol supports the recommendation for daily ingestion of whey protein in potentially reducing chronic disease risk.”
They added that a synergistic effect from combined protein ingestion and exercise could contribute to the management of total cholesterol levels.
Whey protein also reduced triglyceride levels, partly due to physiological responses that improve lipid metabolism. It has also been shown to increase fat oxidation, enhance insulin sensitivity and decrease hepatic triglyceride synthesis in rat models, according to the analysis.
“Our meta-analyses revealed that whey protein supplementation may lower SBP, LDL-cholesterol, and total cholesterol levels compared with placebo, with exercise conferring an additive effect,” the researchers concluded. “Moreover, subgroup analyses revealed a greater response to LDL-cholesterol and SBP via whey protein supplementation in adults aged <50 years of age, while reductions in HDL-cholesterol, total cholesterol, and triglyceride were primarily observed in healthy adults as opposed to adults with overweight and/or obesity.”
For future study, they called for further investigations into the long-term effects and potential variations across diverse populations to establish a broader applicability of their observations.
Source: Clinical Nutrition. doi: 10.1016/j.clnu.2024.12.003. “The effects of whey protein supplementation on indices of cardiometabolic health: A systematic review and meta-analysis of randomized controlled trials”. Authors: Konstantinos Prokopidis et al.
