Which nutrients are critical for maintaining energy levels?

Carbohydrates, proteins, and fats are the primary macronutrients that provide the body with energy. Carbohydrates are the body's main source of quick energy. When consumed, they are broken down into glucose, which is used directly by cells for fuel or stored as glycogen for later use. Proteins, while primarily involved in building and repairing tissues, can also be converted to energy if necessary during prolonged exercise or when carbohydrate stores are low. Fats are essential for sustained energy, particularly during extended periods of activity; they provide a dense energy source that the body can utilize during lower-intensity exercise over a longer duration.

The other options, while important for various functions in the body, do not primarily supply energy. Vitamins and minerals (first option) are crucial for processes that involve energy production and overall health but do not provide energy directly. Water and fiber (third option) are vital for maintaining bodily functions and digestion but do not contribute caloric energy. Antioxidants and omega-3 fatty acids (fourth option) play significant roles in reducing inflammation and supporting overall health but are not direct sources of energy for the body. Thus, carbohydrates, proteins, and fats are the key nutrients that maintain energy levels effectively.