Intermittent fasting: the best pros / cons health ratio

intermittent fasting skipping breakfast - comic

Intermittent fasting has become very famous. It mostly known as an efficent solution to loose weight, but it actually hides a tremendous amount of health benefits.

What is intermittent fasting, exactly?

Intermittent fasting is simply the fact of stretching the duration that separates two meals. The goal is to exit the postprandial state in order to enter the fasting state. The postprandial state is when nutrients are absorbed by the digestive track and released into the blood stream, which is, after meals. Between 8 to 12 hours after a meal, the body transition from the fasting state. If you have a dinner until 8:30pm, and then a breakfast at 8:30am, only 12 hours were spent and your body may have enough reserves not to switch into the fasting state.

Health benefits

Benefits are countless. I seleted only those who seem the more accurate to me, but there exists many more.

Insulin blood level regulation

Insulin resistance is the process that precedes type 2 diabetes. This disruption comes from an excessive carbs intake, over a long period of time. It is quite expected that, conversly, a shortage of carbs regulates this mechanism1.

Schema of the type 2 diabetes
Insulin resistance prevent some glucose to access the muscles and the organs

The body first uses the glucose available in the blood, then the glycogen stored in the liver, along with the glycogen stored in the muscles (expected behavior that, despite what some people may believe, doesn’t shrink the muscle mass). It must then switch mode in order to get its energy from the fats. During short intermittent fasting periods, this mecanism is barely used because the body has a lot of reserves. Still, that is enough to regulate the insulin blood level and fix insulin resistance. Needless to say, that works only when done over sufficient period of time…

glucose and insulin with 3 meals - schema
With 3 meals a day, insulin and glucose are permanently active to feed the body.
glucose and insulin with 2 meals a day - schema
Skipping breakfast fixes insuline resistance by lowering insuline blood levels.

Knowing all the risks related to insulin resistance and diabetes, that’s definitely a big deal!

Weight loss

Weight loss is directly linked to insulin blood level reuglation. While the insulin level is high, you can’t loose weight. Intermittent fasting lowers that level and thus makes it possible to burn fats.

Beyond the aesthetic aspect of loosing wheight, this especially enables to lower the risk of cardio-vascular diseases2.

loosing weight selfies - comic
Selfie before / after

Conversly, if you are a bit too skinny, fasting can become dangerous because it needs a minimum amount of fat in order to prevent burning the vital reserves.

Increase in growth hormone secretion

Like sport, intermittent fasting can increase the growth hormone release. This hormone trigger growth in kids, but also cell repair an renewal. Which statistically raise your lifespan.

growth hormone released into the body
The growth hormone is released by the hypothalamus

This hormone stimuation triggers a rise of the metabolism. You will consequently use up more energy and loose weight more easily (whether you want to or not).

Oxidative stress reduction

Oxidative stress is a bit like rust in the body. Brain, organs, skin, articulations, nothing is safe. It plays a core role in chronic and degenerative diseases.

oxidative stress lowering - comic
Very scientific drawing

Some studies prove that intermittent fasting can reduce that oxidative stress and inflamations by increasing the production of natural antioxidants3.

Heading back to the intermittent fasing protocol

I hope that you now feel like trying. So let’s head back to the principle of intermittent fasting.

Nope, it is not a diet

The big plus is that it is not a diet. Intermittent fasting does not change WHAT you eat, but it changes WHEN you eat.

In that way, it is much easier that most diets / cleanse, because that means less constraints: you can keep your food habits. And less social pressure: nobody saw that you skipped breakfast, and nobody is judging your plate in a weird way, because you just eat like everybody else.

With a bit of unwillingness, you can thus do intermittent fasting and it like shit. It’s definitely possible. But bad food habits act as a severe aggression and you may therefore not profit from all the promised benefits. A balanced diet is obviously always advised, wheter you fast or not.

How long without eating?

There is an infinite number of combinations. The most common pattern is a period of 16 hours without eating: one meal at 1pm and another one at 8pm. So, no breakfast there. You must idealy reproduce this patter every day in order to experience the positive effects. Setting a routine enable the body to get used to it and not panicking anymore when it is deprived of food.

It is up to you to experience what fits you the best. Some will prefer skipping dinner. Some prefer fasting for a whole day per week. Some make it to only one meal a day, two times a week. Some diets go way beyond that. Try various combinations and see what seems the most natural to you. The beginning is often the hardest, so let yourself a chance to make it and don’t give up on the first few days.

exemples of intermittent fasting - table
Exemples of intermittent fasting schedules

The key point is to find a combination that will suit your way of life. If you work for a company, you can’t really delay lunch time that much.

The myth of 3 meals a day (or more)

Who never heard that you need to feed at least 3 times a day? And that breakfast was the most important meal of all? And that snacking can help against lows?

Actually, that was bullshit, set up by the food industry. There is no scientific proof of that.

Humans are animals. Animals (not your pet, but in the wild) eat when they are hungry and when they managed to find some food. The chances that it comes up to 3 meals a day, every day, is quite low. Sometimes, there is nothing to eat. The body takes advantage of that moment to do something else (like cleaning). I know there is nothing scientifique in that, but for me, that makes sense.

We could argue for a while about whether it’s logical or natural or not. Luckily, the benefits of intermittent fasting have been proven and we now know that it’s great: end of the debate \o/

Skipping a meal will simulate that temporary food shortage, which will force the body into exiting its comfort zone. It will then activate some forgotten mechanisms.

The main issue is that our whole life is built up upon those 3 meals a day (or even more). So it’s quite hard to eat only when you want to. That’s the reason why skipping a meal is the easiest way for most of us.

Important rule: if you’re not hungry, do not force yourself into eating. Listening to your body is a basic move. Not listening to the advices of the food industry is also wise.

There is also another myth in popular believes: “when you skip a meal, the body will store more in order to compensate the loss“. Bullshit again. It has been demonstrated that intermittent fasting is associated to a weight loss of overweight people. Plus, if you think about it for a sec: if your body is capable of storing more, that may also mean that it just became more efficient, right? Besides, intermittent fasting mecanisms are much less powerful than those of long term fasting.


Depending on your daily habits, the first days may come up difficult. Your body has never been deprived of glucose and it doesn’t know what to do otherwise. You will experience a few moments of fatigue and cravings.

hungry - comic

If you keep on (and you will), you will feel that the body slowly gets used to it. You will not experience intense cravings anymore (maybe some small ones, but you can handle it). Also, you sensation of wellness may increase and you should feel better.


During the fasting stage, you can of course drink water (unless you don’t feel thirsty). Coffee, tea and other calories free are allowed. But, no sugar into the coffee! Just black. And it is not an excuse for drinking to much of it either.


Drinking water or green tea or an infusion in order to fill up the stomach is a very efficient solution to bypass the craving sensations.


Exercising while fating stimulates the metabolism. The body needs energy and the glucose is missing. It imperatively has to active the plan B.

running - comic

So, don’t go challenge yourself too hard (especially in the beginning), but if you feel for it, don’t hesitate to add some sport or even just walking to your fasting stages in order to multiply its effects.


Intermittent fasting is without a doubt one of the most benefical health pattern if you consider the ratio constraints / benefits. Still, it can be hard for the first few days because the body is not used to be deprived of energy. Once that problem is behind, it’s not a big deal anymore!

If you have any questions about intermittent fasting, do not hesitate to ask me using the comments below.

  1. Effect of intermittent fasting and refeeding on insulin action in healthy men.
  2. The Effects of Intermittent Energy Restriction on Indices of Cardiometabolic Health
  3. Alternate day calorie restriction improves clinical findings and reduces markers of oxidative stress and inflammation in overweight adults with moderate asthma.

2 thoughts on “Intermittent fasting: the best pros / cons health ratio”

  1. Awesome article! thank you! I just started keto and want to maximize my weight loss by implementing IF. I know you posted a table of possible eating schedules but can you tell me what a good hour ratio is if I want to fast every day/How many hours of not eating at the least is effective for your body to kick in to fasting mode? I wake up at 7am and am usually not hungry until about noon. I am a big night time eater and stay up until about midnight. So what would you suggest a good ratio (eating window/fasting window) for me to be? Thank you for your time 🙂

    1. Hi kirstin.
      If you are already on a keto diet and skipping breakfast, that’s a great plan for weight loss. Don’t put too much pressure on yourself though. At least for now. You don’t want to loose weight too fast. That wouldn’t be healthy. I suggest you try to have lunch one hour later every week. So at 1pm the first week, 2pm the 3rd week. At some point, your body is gonna tell you if you go too far. Just listen.
      Enjoy en keep me in touch!

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