What is the primary source of energy for the brain?

The brain primarily relies on glucose as its main source of energy. This carbohydrate serves as the primary fuel for neuronal activity and is crucial for maintaining cognitive functions such as memory and attention. Glucose is readily available in the bloodstream and is transported into brain cells, where it undergoes metabolic processes to produce the energy needed for various brain functions.

While fatty acids can be utilized as an alternative energy source during prolonged fasting or low carbohydrate availability, glucose remains the preferred and most efficient fuel for the brain under normal circumstances. Proteins typically serve other roles in the body, such as building and repairing tissues, rather than functioning as a direct energy source for the brain. Additionally, vitamins play essential roles in metabolic processes and overall health but do not provide energy in the form that glucose does. Thus, glucose's significance as the primary energy source for the brain is well-established in nutrition science.