Microblog: The Body Does Not Just Run on Glucose or Ketones

Why do we only talk gluconeogenesis?

❗️There are other fatty acids than ketones.

❓Do we need glucose in the body?

Yes.

❓Does it need to come from food?

No.

🍬Here are some ways our body mechanistically uses, stores, and breaks down energy in the body for glucose (had to dig back from my board exam):

🔅GLYCOGENESIS: liver converts glucose to glycogen and stores it for future use.

💡The average adult can store about 100 gr of glycogen in the liver, about 10% of the organ’s weight. Skeletal muscle cells also convert blood glucose to glycogen (via glycogenesis), and store it locally.

💡The average adult can store about 400 gr of glycogen in the muscles, accounting for 1 to 2% of muscle mass. (glycogen stores in the muscles can only be used locally, liver glycogen can be used anywhere)

🔅LIPOGENESIS: When the liver and muscle glycogen stores are full, the liver then converts any remaining glucose to TRIGLYCERIDES, which are then stored in fat cells. (why trigs are low on a keto diet)

🔅LIPOLYSIS: The breakdown of triglycerides (stored in body fat) into GLYCEROL and free fatty acids. (When blood sugar is low, fat cells release free fatty acids into the blood)

🔅GLYCOGENOLYSIS: Converting glycogen back to glucose for energy

🔅GLUCONEOGENESIS: Protein converted to glucose within the liver (lactate, GLYCEROL, and amino acids to glucose)

🔅GLYCOLYSIS: The metabolic pathway that converts glucose into pyruvate, which can then enter the Citric Acid Cycle. (Krebs)

🔅KETOGENESIS: Converting fatty acids into ketones in the liver

⛑Don’t worry about all the terms but know that there are MANY mechanisms for the body to produce glucose within the body.

🧬The body leverages insulin and glucagon hormones to pull all these energy levers (pancreas—where digestive enzymes are made).

⁉️Do you see how fat via LIPOLYSIS > GLYCEROL can ALSO be converted to glucose for energy?

💡Our body does not require an external glucose source for glucose.