Food-health claims are an important method of translating nutrition research to consumers. Whey and colostrum are thought to exert health benefits to adults, but it is unclear what measurable, objective health benefits they impart. This review aimed to identify the objective health benefits of bovine whey or colostrum-based beverages to healthy adults aged ≥35 years to substantiate a food-health claim. Seven databases were systematically searched. Eligible articles were RCTs that involved healthy adults aged ≥35 years, consuming whey or colostrum in beverage form and measuring objective health markers. Quality assessment and data extraction was conducted in duplicate. The searches identified 9943 papers and 16 were included in this review; 13 studies, reported across 15 papers, related to whey, one study to colostrum. The outcomes identified were body composition, bone mineral density, biochemical markers, such as blood glucose and lipids, and muscle strength and synthesis. Heterogeneous outcomes, high risk of bias and inconsistent findings resulted in inconclusive evidence to substantiate a food-health claim. Clearer reporting and consensus on a minimum set of objective measures would allow for more robust recommendations regarding food-health claims. Protecting consumers from misleading health claims will require collaboration between regulators, researchers, and the food industry.