Which macronutrient provides the highest energy yield per gram?

Fats provide the highest energy yield per gram compared to other macronutrients. Each gram of fat delivers approximately 9 calories of energy, making it significantly more energy-dense than proteins and carbohydrates, which provide about 4 calories per gram each. This higher caloric content makes fats an efficient source of energy for the body, particularly during prolonged physical activities or during periods when the body is in a state of fasting, as the body will often rely on fat stores for energy.

In the context of nutrition, understanding the energy yield of macronutrients is essential for formulating diets, planning meals, and advising individuals on energy requirements based on their activity levels and health goals. Fats not only serve as a concentrated energy source but also play vital roles in the absorption of fat-soluble vitamins and provide essential fatty acids that the body cannot synthesize on its own.