The science of dietary fats has evolved, and a body of evidence indicates they are complex bioactive nutrients that have different effects on health depending on their food source, chain length, degree of saturation, and other factors that can be affected by food processing, handling, and storage. As such, it is becoming increasingly clear that the effects of foods on obesity and metabolic health cannot be predicted simply with their fat content. The aim of this opinion article is to provide a brief overview of select recent research on the effects of whole-milk dairy foods on body composition and indicators of metabolic health across the lifespan to show the gap between current knowledge and dietary guidance. As the state of the science on dietary fats and human health evolves to consider the complexity of food matrices, the total nutrient package they deliver, and the health impacts associated with dietary patterns, so too must guidelines for dietary fat.
Keywords: dietary fat; dietary fat guidance; metabolic disorders; obesity; saturated fat; whole-milk dairy foods.