Registered Dietitian Practice Test

An isotonic enteral formula is designed to have an osmolality similar to that of human plasma, which is typically around 280 to 300 mOsm/kg. This characteristic helps to ensure that the formula can be absorbed effectively without causing significant shifts in fluid from the intravascular compartment, thus minimizing the risk of gastrointestinal distress or complications like diarrhea. In practice, when a formula is isotonic, it allows for the maintenance of fluid balance and proper nutrient absorption. Formulas with an osmolality around 300 mOsm/kg are specifically formulated to match human physiological conditions, which is why this value is widely accepted in clinical nutrition. Various factors, such as the presence of carbohydrates, proteins, and other solutes in the formula, contribute to its total osmolality. Therefore, the correct answer of 300 mOsm/kg signifies that the formula is designed to be well-tolerated by the body, promoting optimal nutrient utilization and patient comfort during enteral feeding.