Hey Guys, Welcome back to my blog 🙂 As we are moving on to the Carbohydrates topic I would hope that through my four previous reflections that you guys got a good grasp on the topic Cells.
Today we are going to look at glucose and why is it that glucose is the sole fuel for the human brain and nervous system.
Except in prolonged periods of starvation, glucose is the sole fuel for the human brain. This is because the brain lacks fuel stores and it requires a continuous supply of glucose. According to statistics, the brain consumes about 120g daily accounting for 60% of the utilization of glucose by the whole body in the resting state. It is suggested that over 50% of this energy is used to power transport mechanisms that maintain the Na+-K+ membrane potential required for the transmission of the nerve impulses. The brain must also synthesize neurotransmitters and their receptors. Overall, during mental activity glucose metabolism remains relatively unchanged, although there has been signs of some increase from certain activities carried out. Glucose is transported into brain cells by the glucose transporter GLUT3.
When doing research I found out that fatty acids do not serve as a fuel for the brain because they are bound to albumin in plasma and do not traverse the blood brain barrier. However in starvation, ketone bodies are generated by the liver partly replacing glucose as fuel for the brain.
Hope this was a bit informative. Thanks for reading 🙂