Intermittent Fasting: What is it and how does it work?

Intermittent fasting, like other weight loss methods, is recommended by celebrities and CEOs because of its weight loss and health benefits.

There is promising evidence that fasting can help our body regenerate and prolong life, but it may not be the best way to lose weight, and dietitians should be careful before restricting their diet.

Should You Try Intermittent Fasting to Lose Weight?

Intermittent fasting

Is a type of diet with a time limit that increases the time between the last meal of the day and the first meal of the next day, compressing the meal into shorter times of the day.

Faster people usually move at 16-hour intervals without eating and try to eat in an 8-hour time frame. Intermittent fasting is not the only form of a time-limited diet.

Others, like a 5: 2 diet (participants eat a normal amount of food for 5 days and then consume 25% of their normal calorie intake for 2 days), rather than the time between meals. Focus on the amount of food. ..
“Timed meals are used as a weight-loss tool, but that’s not my favorite approach,” says Rachel Clarkeson, founder of London-based consulting firm The DNA Dietitian.

“You are reducing calories, but you have not learned important behavioral changes about how to feed your body.”

people who didn’t know what a healthy diet would look like would gain weight when they stopped fasting. “If you feel hungry and restricted, you may overeat the next day.

Intermittent fasting may not be the right way for people trying to lose weight, but there may be other reasons to change your diet.

Fasting is associated with a process called autophagy, which has received a lot of attention for its potential health benefits.


Autophagy is the process by which the body begins to recycle the intracellular structures that contain the nucleus where DNA is stored.

Mitochondria synthesize the chemicals that our cells use to generate energy. Lysosomes remove waste products from cells. In this way, the cell can remove the defective structure and release new raw materials to build a new cell structure.

Some of these new ingredients can be used to make protective proteins that further extend the lifespan of cells.

Intermittent fasting

There is also the question of whether autophagy can extend the lifespan of the entire organism, but this hypothesis has so far only been reproduced in animals such as nematodes and 1 mm long mice and has not been reproduced in humans.

No (inhibition of autophagy is also associated with premature aging). … It is premature to say that it will extend our lifespan until a longitudinal study of people practicing intermittent fasting is done.
However, in other animal studies, autophagy is associated with improved memory of the immune system.

The fact that autophagy is essential for maintaining cell health has also sparked interest in its role in the fight against cancer.

In addition to extending lifespan, there may be other reasons for your interest in autophagy.

For most of us, autophagy occurs during sleep, but it can also be caused by exercise and starvation.

Can a controlled Intermittent fasting help cause it?

Unlike a low-calorie diet (which is also associated with longevity), the goal of an intermittent fast is to increase the time interval between the last meal of the day and the first meal of the next day.

Theoretically, people who fast intermittently can burn the same amount of calories as they normally do, but in practice, most people reduce their intake slightly.
Even if you stop eating at 7 pm, you will remain in a “refueling” state until 10 pm. We’re still digesting the nutrients, “.

All carbohydrates in our diet provide glucose, the main fuel source, for several hours.
In saturation, the body uses blood sugar as an energy source. When this energy source is exhausted, the body usually becomes catabolic about 3 hours after eating.

At this stage, glycogen stored in the liver and muscles is converted to glucose. Once glycogen stores are depleted, the body switches from glucose to ketones, which are formed in the liver from fatty acids.

At this point, in a phase called ketosis, autophagy is activated. “We don’t know exactly when the switch from glucose to ketones occurs,” 

“It depends on a lot of things: genetics, health, lifestyle. The amount of glycogen available depends on what you’ve eaten and how much energy you expend.

People on a high-carb diet will not go beyond catabolism because they still have glycogen stored.

However, people on a low-carb diet who exercise regularly can overcome this problem very quickly (as well as a “ketogenic diet” that cuts almost all carbs to keep blood sugar and glycogen storage low.

“We don’t recommend intermittent fasting because of fat loss. If you’re using it, you need to think about its health benefits,”.

How to make it faster ?

Fasting is about reducing the feeling of hunger. Hunger occurs when the hormone ghrelin released from the stomach causes the production of two other hormones, NPY and AgRP, in the hypothalamus.

These three hormones cause a feeling of hunger, while other hormones suppress it. One of the important satiety hormones is leptin.

Leptin is released from fat cells and suppresses the production of ghrelin, which tells the body “this is the fat you can burn.
Ghrelin is also known as a short-term response to hunger because it is released when the stomach is emptied and the pressure on the stomach wall is low.

Intermittent fasting

It can be supplemented to some extent by drinking water. Leptin, on the other hand, has long-term effects.
“Our hunger hormones are regulated by many factors, including genetics,” explains Clarkson.

But when you think about the nerves that connect the stomach to the digestive tract, you think your body is hungry when your stomach isn’t full.

He adds that adequate fluid intake can help overcome the initial feeling of hunger until the body gets used to it. “The first few weeks will be difficult, but then you get used to it,” he says.

For most people, ketosis occurs 12 to 24 hours after the meal. So if dinner is eaten between 6 p.m. and 8:30 p.m., the nutritional state ends between 9 p.m. and 11:30 p.m., while ketosis and autophagy can occur between 6 a.m. and 8:30 a.m. the next morning.

“But most people sit down after dinner and open a package of something else,”. If you finish your snack at 9:30 pm, your diet will continue until 1:30 am,”.

This may mean that ketosis does not occur until the next meal.
If you consciously eat dinner an hour before and choose not to snack between meals, you may get ketosis in the morning, but those who eat high-carbohydrate meals and snacks get up at 6 am. , Never enter ketosis.

Starting a meal early on Sunday night or having breakfast an hour later and gaining weight one or two days a week. With care, intermittent fasting can help the body recover and heal.

Self-feeding seems to decrease with age, so it may be helpful to give yourself an additional boost as you get older.

However, it is important to understand that this is not the right strategy for losing weight and cannot be replaced by a balanced diet.