You have to make your body metabolically flexible and get used to getting energy from both carbohydrates and fat reserves.
If you don't eat carbohydrates, your body produces glucose in the liver without problems if you are a healthy person. Be careful, we are not saying that carbohydrates are bad or that you should stop consuming them, we are just clarifying that your body is capable of maintaining the level of glucose you need in your blood, even if you do not consume carbohydrates.
For years we have been sold a nutritional pyramid in which BSA is full of carbohydrates, telling us that they should be our main source of food.
And it is not true. If you are a person who does not practice sports and do not move much, you will probably do much better by eating very few carbohydrates.
When we eat, the liver stores glucose in the form of glycogen for when we need it.
The liver can convert glycogen to glucose through a process called glycogenolysis. And it can also make glucose if we haven't eaten carbohydrates by collecting amino acids through a process called gluconeogenesis.
The liver can also make ketones , another fuel for the body, when we are low on glucose. Our body is responsible for storing the sugar it has for those organs that need it and the liver manufactures ketones to supplement the limited sugar reserves.
Ketones are used for energy by muscles and other body organs.
The liver is responsible for manufacturing this alternative fuel that comes from fats through a process called ketogenesis. This process begins when hormones indicate that there is a low level of insulin in the body and is essential to maintain minimum glucose levels during fasting periods.