Question

How long does it take the muscle to start synthesizing ketones after it runs out of glucose to synthesize? When the transition occurs, does this affect the brain in a specific way? If you used a website to answer this could you please attach it.

Answer 1

Ketone bodies are usually present in the human body in a very low amount. when the human body goes under starvation i.e. they don't get their regular supply of glucose for body functions then the body activates the ketogenesis process in which it creates ketone bodies from the stored fatty acids which then is used by our organs,.Intially after staving for overnight the ketone concentration increase up to 6-7%. After 3 days of starvation, the ketone concentration increases up to 40% and ketone is used in the metabolic process to get energy for various body function.

Like any other organ brain also gets its fuel requirement from ketone bodies in the absence of glucose. During the Initial days of starvation the brain gets around 25% of its energy from ketone bodies after prolong starvation for around 3 weeks it reaches up to 70%. Although the brain uses 100-150 grams of glucose per day while ketone body only provides between 15-30 grams of it. This decrease in fuel intake prolongs the death which will happen in 10 days if ketone bodies starts providing the same amount but instead a person survives up to 50-70 days due to the decrement.