Which cells can only utilize glucose as an energy source?

Nerve cells, or neurons, predominantly rely on glucose as their primary energy source. This reliance is due to their high energy demands, which are necessary for maintaining the electrochemical gradients essential for nerve impulse transmission. Unlike many other cell types, neurons have a limited capacity to utilize fatty acids or other substrates for energy, making glucose the critical fuel for their functioning and survival.

This characteristic is particularly important in situations of hypoglycemia, where the brain can suffer significant impairments because it lacks an alternative energy source. Neurons do not store glucose; instead, they depend on a continuous supply from the blood, underscoring their exclusive reliance on glucose for maintenance of neuronal health and activity.

In contrast, muscle, intestine, and skin cells can utilize a variety of energy sources, including fatty acids and amino acids, depending on the metabolic demands and the physiological state. Thus, those cell types do not share the strict glucose dependency that nerve cells exhibit.