Purpose: The dietary egg-protein hydrolysate Newtricious (NWT)-03 has previously demonstrated improvements in blood pressure and metabolic profiles. However, the long-term effects on vascular function and cardiometabolic risk markers are unknown.

Methods: Forty-four older (aged 60-75) adults with overweight/obesity experiencing elevated Subjective Cognitive Failures (SCF) were randomized into a 36-week, double-blind, placebo-controlled trial. Participants either consumed 5.7 g of an egg-protein hydrolysate (NWT-03) or maltodextrin placebo. Endothelial function (brachial artery flow-mediated vasodilation [FMD] and carotid artery reactivity [CAR] responses after a cold pressor test), arterial stiffness (carotid-to-femoral pulse wave velocity [PWV(c-f)]), retinal microvascular calibers, and cardiometabolic risk markers (insulin sensitivity using a 7-point oral glucose tolerance test, serum lipid profiles, and blood pressure) were evaluated.

Results: FMD observed a non-significant trend towards a 0.3 percentage point (pp) increase in the intervention compared to the placebo group (95% CI: [0.0, 0.7]; p = 0.08), and a significant intervention effect was observed on CAR responses based on a 0.7 pp improvement after a cold pressor test (95% CI: [0.1, 1.3]; p = 0.03). No significant overall changes were observed for arterial stiffness as measured by PWV(c-f). Retinal microvascular calibers and cardiometabolic parameters also did not change.

Conclusion: Long-term supplementation with 5.7 g of the egg-protein hydrolysate NWT-03 for 36 weeks improved vascular endothelial function in older adults with overweight/obesity experiencing elevated SCF, which may benefit cardiovascular disease risk. No overall changes in other vascular function markers, retinal microvascular calibers or cardiometabolic risk markers were observed.

Clinical trial registration: The study was registered at ClinicalTrials.gov in January 2021 as NCT04831203: https://clinicaltrials.gov/study/NCT04831203.