Which nutrient generates the most energy per gram?

Fats are known to generate the most energy per gram compared to other nutrients. When metabolized, fats provide approximately 9 calories per gram, which is significantly higher than carbohydrates and proteins, both of which yield about 4 calories per gram. This high energy density is one of the reasons fats are an important energy source for the body, particularly during prolonged physical activity when energy demands are high. Additionally, fats play critical roles in the absorption of fat-soluble vitamins and the production of hormones, contributing to overall health and performance.

In contrast, carbohydrates and proteins serve other primary functions in the body despite their role in providing energy. Carbohydrates are the body's preferred energy source for high-intensity activities, while proteins are mainly involved in tissue repair and muscle synthesis. Vitamins are essential for various metabolic processes but do not provide energy directly. This distinction underscores the importance of fats as a dense energy source in nutrition.