What macronutrient serves as a major energy supplier for the body?

The macronutrient that serves as a major energy supplier for the body is carbohydrates. Carbohydrates are the body's primary and preferred source of energy, especially for high-intensity activities. When consumed, they are broken down into glucose, which is used by cells for immediate energy or stored as glycogen in muscles and the liver for later use.

While fats also provide energy, they are utilized primarily during low-intensity activities and when carbohydrate stores are depleted. Proteins, on the other hand, primarily serve functions such as building and repairing tissues, and they are not the body's first choice as an energy source. Fiber, an essential component of a balanced diet, plays a critical role in digestive health but does not serve as an energy supplier like carbohydrates, fats, or proteins.

In summary, carbohydrates are the main macronutrient utilized for energy, which is fundamental for fueling daily activities and overall bodily functions.