Fasting can be an incredibly powerful tool to jump-start a healthier lifestyle. It may not suit everyone, but it also doesn't have to be as difficult as many people think. There are different ways to fast and often it's about finding the way that suits you.

Why should we fast? What do we get out of a fast? On the one hand, it can be an effective way to lose a few kilos and increase your fat burning. But it is also a very good way to bring down your blood sugar and thus lower your insulin levels. Lowered insulin levels in the body give the body room to burn stored fat. Many people find that with the help of fasting they can reach a more stable and balanced blood sugar.

Already after 12 hours without food, the body is put into a fasting state and the insulin level is lowered. If we do not fill up with food, the body starts to use the stored sugar, the so-called glycogen. It usually lasts for about a day. If we choose to fast longer, the body will regulate energy levels first by converting amino acids into glucose, i.e. sugar, and then switch to using stored fat for fuel. At the same time, the body's metabolism increases. Important to point out here that when the body converts amino acids into glucose to create fuel, we should see it more as a cleaning process in the body. It is not muscle that is directly broken down, but excess protein that is converted into glucose.

This can be interesting to compare with diets that involve calorie restriction for a longer period. Instead, the body's metabolism drops and it becomes easier to put on kilos again when you let go of the calorie restriction.

When we eat, it always becomes a high priority for the body to take care of this food to convert it into energy or building blocks in the body. When we let the body rest from food intake and let it come to this phase we refer to here as the cleaning process, then the body can focus on other things and amazing things can happen. As already mentioned, excess is automatically cleaned out. A process in the body called Autophagy increases significantly. Autophagy is actually about cell death. It might sound scary, but it's actually extremely important. The cells break down worn-out components and then give the body the opportunity to replace them with new, fresh ones. Our cells are actually programmed to have a certain lifespan. How long depends a bit on the type of cell it is but everyone has a programmed lifespan and we don't actually want the cells to outlive that lifespan. Instead, we want to leave room for new, fresh cells.

After about 24 hours of fasting, autophagy kicks into action in the body and after 36 hours of fasting, it has increased significantly. After about 4 days of fasting, autophagy has reached maximum levels and stays there. This is what we mean when we talk about cleaning process. 

After a longer fast like this, you also see that the inflammatory markers in the body go down and the immune system renews itself.

How we should fast depends on what we want to achieve with our fasting. As said, the cleaning process already starts after about a day, but of course has more effect if you continue to fast for a few more days. If your goal with the fast is more about getting rid of a few kilos, you can also achieve it with a shorter fast.

Intermittent fasting

Also called intermittent fasting. It's about lowering your so-called eating window on the day you fast. You eat for 8 hours out of the 24 hours of the day and thus fast for 16 hours. The most common is that the eating window lasts between 12 in the day and 8 in the evening. In between, you abstain from food but drink water, tea or coffee. For many, this form of fasting is a good way to get off to a soft start. It is relatively easy to achieve in everyday life, and there is also no social pressure to explain why you don't eat.

The so-called 5:2 method is also a periodic fast. The difference there is that you eat as you usually do 5 days a week, while the other two have a maximum intake of 500 calories if you are a woman and 600 calories if you are a man.

One-day fasting

Here you abstain from food completely for one day. Or it will actually be longer as you usually stop eating in the evening, abstain from food for the entire next day and then eat for the first time the morning after. 

Multi-day fast

During a multi-day fast, you abstain from food for 3-5 days. Hardcore is water fasting for several days. Please read carefully and prepare properly for such a fast. I myself have also tried fasting for so many days, but have then indulged myself in drinking bone broth a few times a day. It has quelled the worst of the hunger plus the broth contains enough nutrition to make fasting easier to manage.

Fasting mimicking diet

Another way of fasting that has become very popular. Here you get all the benefits of a fast without actually fasting. How? Well you eat three times a day but with a special set of carbohydrates and fat and at the same time minimal protein. The portions are not large, but you still eat a little three times a day. Something many find a relief. 

No matter what form of fasting you do, it can be worth thinking healthily after the fast. Here you've just completed this amazing cleansing of your body and got your blood sugar down, lowered your insulin levels. You can see it as having turned a new page and that here you have every opportunity to fill your body with plenty of nutrition and building blocks. Feel free to think of all the colors of the rainbow together with healthy proteins and fats.

When should we not fast?

We would not recommend you to fast when you are pregnant. Nor if you have a history of eating disorders or suffer from any form of thyroid disease. Even if you have a history of fatigue syndrome or feel that your health is greatly affected by stress. If you are being treated for any other illness, I think you should consult your doctor before you fast.

You may have to experiment to find out which fast is right for you. Why not start with intermittent fasting to see how you react to fasting. How you handle hunger perhaps. Then possibly go further and try fasting for a longer period. At a later date, we can also go through how different types of fasting work better or worse if you are a man or a woman. It unaffected much of our hormonal makeup. But to begin with, I would recommend you to test and listen to your body. Often it signals clearly whether this is something for you or not.

I myself was nervous before my first fast. Always felt that I was more of a person who needs to eat a little but often to keep the energy going. Started by trying the 16:8 method. So I was surprised when I realized that I have never had such balanced energy levels as when I fast. My usual afternoon dip disappeared and the hunger, which I also worried about, was much easier to manage than I thought. Another plus on the edge is that food never tastes as good as when you break a fast. It's like the whole body is on alert:)

After realizing that fasting actually works for me, I've also tried longer fasts and think it's amazing. Especially afterwards 😉

A fast can feel tough if you are alone. Maybe try together with a friend and encourage each other. Feel free to share your own thoughts about fasting on instagram @scriptnutrition so we can encourage each other.

Anna Fagerström, Functional medicine therapist