I was wondering all of this and so it was time to invite Samefko Ludidi to my 'Drive' Podcast. He is a nutrition and exercise scientist and wrote the book 'the Fasting Method' which is about this method of fasting.
M: What is intermittent fasting?
S: In the society we live in, our machine, our metabolism, runs mainly on carbohydrates. If you don't eat for long periods of time, these reserves get depleted. When this happens, fats have to take over as fuel. The body's own fats are used as fuel in the body after twelve hours. Normally, you eat at seven or eight o'clock at night at the latest, but now you eat twelve hours later. You actually eat breakfast just at the time your body switches to fat as an energy source. So, you never give your body a chance to use fat as fuel. If you extend this by five or six hours, you give your body a chance to switch.
So intermittent fasting is moving away from the standard ""eat three times a day"" routine we all find so common and switch to 16:8 routine. Meaning that you will not eat for sixteen hours bu only drink water, then eat normally within a maximum of eight hours. For example, you could skip your breakfast and thus only eat between lunch and dinner time.
M: Does this work right away?
S: No, your body needs time to adapt. Often, the beginning is most difficult as your body is not used to making that switch to fat burning. You may be a little more tired the first two weeks. When you start intermittent fasting, really take the time during the first two weeks to get used to this. Drink enough water, don't exercise too much or too hard, and take a small step back.
M: How do you keep this up?
S: With fasting, you actually stimulate your body's biological mechanism to act in times of food scarcity. Nowadays, we have food in abundance; it used to be different. Periods of abundance and scarcity alternated. So we need to reinstate this. What this means is that you should not fast continuously but cyclically. So in periods of, let's say, eight weeks twice a year. Six to eight weeks twice a year is good to do, it's not necessary to do more.
M: Scientists say that you just have to use calorie restriction to lose weight. No matter what method you follow, simply eating less than you burn will make you lose weight. How do you see this?
S: On the one hand, people find it more difficult to eat a little bit four or five times a day than not to eat a whole day, when it comes to calorie restriction. There are plenty of studies that indicate that there are actually adjustments in your metabolism as a result of fasting. There are many different methods of intermittent fasting. Calorie deficit is an effect that occurs more easily with longer fasts such as not eating for two days in a row. With daily fasting for, say, sixteen hours, you can easily take in as many calories as normal.
M: Another benefit would be to promote the process of cell repair?
S: That is certainly true and explainable. You have to look at it this way. If you don't eat for more than 24 hours, your body thinks that there is not enough new food coming in for a longer time and it will automatically scale back cell division a bit. Cell division can only happen a limited number of times. With each division there is a risk of dividing the wrong cells. The moment no food comes in for a long time, the body actually says, instead of making new cells, let's see how we can repair the ones we have. We call that process 'autophagy', which is why fasting is said to have a rejuvenating effect. Better said, it inhibits aging.
M: So this can only be done with prolonged fasting?
S: Yes, that's right. We humans can easily go four or five days without eating. We had to cope with that in the historic past. Our bodies have developed clever ways of dealing with this. Indeed, this process of autophagy occurs when our body is really without food for longer periods of time (days).
M: What methods of intermittent fasting are there?
S: To begin, you have to ask yourself the question: what do you want to achieve? Do you want to lose weight? Then a 16:8 system would be very good because that increases your fat burning versus your carbohydrate burning. So sixteen hours of fasting and eating within eight hours.
If you want to improve your sports performance or be less dependent on food during exercise, then it's different. I coach many athletes, such as Badr Hari. I focus on making these athletes less dependent on food before or during their exercise. This allows them to focus on the exercise itself much better. If you know that you perform well on burning body fat, then you take away the gastrointestinal pressure in your body which promotes performance.
M: Aren't you then losing the energy you actually need in that workout?
S: The question is whether you already have enough reserves in your body to meet the excercise. Muscle glycogen is present, even if you are fasting. That eventually gets depleted, but if your body has gone through that adaptation phase of fasting, it can also simultaneously employ fats as an energy source. If you haven't made the adaptation, you lean very much on carbohydrate burning and need food beforehand.
M: Now what is practical when applying intermittent fasting in workouts?
S: If you want to have the maximum effect on workouts, you actually have to make sure you start training sober and extend that into fasting. For example, I coach Badr Hari in this area. During Ramadan, he was not allowed to eat for 20 hours and still continues to train. When he finished the Ramadan, he was even even fitter. We trained in the morning and he only ate in the evening, so once a day. So, the combination with elite sport is certainly possible, only it is rarely tested. Also make no mistake, you can't just get into this. You have to let your body get used to this. You have to go through this adaptation phase and it can take six to eight weeks. Implementing this in elite sports is also often difficult, because athletes are so used to certain dietary patterns.
M: So, in addition to fasting, eating is also important?
S: Eating well is the basis of fasting, learn what food is good. It should be tasty and nutritious. From there, you start fasting. A common mistake people make is that they both start fasting and eat crackers and salad. If you know why you are doing it, it will help you tremendously, including keeping it up. It seems difficult, but generally we see that people can easily get used to not eating for sixteen hours in a row.
I'm going to give it a try myself anyway. I do always try to watch my food and some periods I deliberately eat a little less. I do a lot on instinct and my gut feeling. What appeals me the most and what I would like to try myself is creating the surprise effect on my body. I know that it is effective to let your body switch gears sometimes and that includes nutrition and burning. Twice eight weeks a year should be doable to me!