> As a backup mechanism your liver can also produce glucose by converting amino acids (muscle) and even fat, a process known as gluconeogenesis. Just a quick n

> As a backup mechanism your liver can also produce glucose by converting amino acids (muscle) and even fat, a process known as gluconeogenesis. Just a quick note, and your explanation is fantastic otherwise: this isn't quite correct. The (human) liver doesn't use fat directly for gluconeogenesis. It's just not efficient for humans: We wouldn't gain enough energy from it. The liver uses fat indirectly through glycerol (which is a product of fatty acid catabolism), but it's important to draw a distinction here because this is why ketosis occurs - if the liver could efficiently break down fat directly, ketosis would never happen at all! Most tissues would much rather use glucose directly if it's an option. While muscle breakdown occurs in small amounts normally it's mostly a last resort that occurs after an extended period of starvation. Which makes sense: You wouldn't want to break down the thing (skeletal muscle) you need to get more food except as a last resort. The amino acids involved in more typical gluconeogenesis largely come from other sources.