Which of the following is the preferred fuel for the functioning of the brain and nerves?

• A. Fatty acids
• B. Amino acids
• C. Lactate
• D. Glucose

Answer: (D)

Verified step by step guidance

1. Understand the role of glucose in the body: Glucose is a simple sugar and the primary energy source for most cells in the body. It is especially important for the brain and nervous system, which rely heavily on glucose for energy due to their high metabolic activity.
2. Recognize why other options are less preferred: Fatty acids and amino acids can be used as energy sources, but they are not the primary fuel for the brain under normal conditions. Fatty acids cannot cross the blood-brain barrier efficiently, and amino acids are primarily used for protein synthesis rather than energy production.
3. Consider lactate: While lactate can be used as an energy source by the brain under certain conditions (e.g., during intense exercise or starvation), it is not the preferred fuel under normal physiological conditions.
4. Recall the importance of glucose in maintaining brain function: The brain consumes a significant portion of the body's glucose supply, and its reliance on glucose is critical for maintaining cognitive functions, nerve signaling, and overall brain health.
5. Conclude that glucose is the preferred fuel for the brain and nerves: Based on the physiological requirements and metabolic pathways, glucose is the correct answer to the question.