A high-protein diet can significantly affect metabolism by increasing the thermic effect of food (TEF), which is the energy required to digest, absorb, and process nutrients. Proteins require more energy to metabolize compared to carbohydrates and fats. This higher TEF can result in a slight increase in daily caloric expenditure. Additionally, protein helps preserve lean muscle mass during weight loss, which is essential for maintaining a healthy metabolic rate. However, it’s vital to balance protein intake with other nutrient needs to support overall health and metabolism effectively.