Fasting for Health – Part 2

Fasting for Health – Part 2

Fasting,Nutrition, TLL LongevityLabs

Let us continue to talk about fasting. Today, we’ll also take a closer look at some critical voices and show you why, despite a certain amount of criticism, interval fasting is definitely the right choice for your health and the health of your body’s cells.

Not everyone is a great fan of fasting. On the contrary: There are people raising their voice to speak up against fasting and interval fasting in particular. Such people often state that the number of human studies looking at the effects of interval fasting conducted with a representative number of participants is rather small and that such studies so far have found little evidence for significant differences in the effects of intermittent fasting compared to other fasting methods. Would you like some examples? Here you are:

Opinions against interval fasting

In her 2016 human study, Krista A. Varady showed that alternating fasting over a period of 8 weeks yields a slight reduction in weight of up to 4 percent compared to the weight at the beginning of the fasting period. However, she failed to proof that interval fasting can result in an improvement of the glucose metabolism. That same year, Paul Carter compared moderate fasting with 5,000 to 6,500 kJ per day and interval fasting and could not find any significant differences in terms of weight loss and glucose metabolism.

In 2017, Nina M. Harder-Lauridsen and her colleagues came to the conclusion that there is no or hardly any difference between the effect of interval fasting compared to other types of diet. However, their study only looked at the Body Mass Index (BMI) and they did not try to validate the effects on the body’s composition, the glucose metabolism and cognitive functions. Let me say as much as that: When taking this approach, the researchers completely ignored the effect of interval fasting on stimulating autophagy.

In 2020, a study conducted by US scientists seemed to confirm this critical view on interval fasting: It found that people fasting according to the 16:8 method did hardly lose any more weight than subjects in the control group. Furthermore, they lost more muscular mass than expected. You probably wonder if we tried to fool you when we told you about the positive effects of interval fasting. No!

Should be regarded with a critically view

Because even the author of the study, the cardiologist Ethan Weiss from the University of California, said that the results leave room for misinterpretation. In fact, the obese subjects were split up into two groups: One group ate their three meals per day just like they always did and the second group followed a diet using the 16:8 fasting method. Both groups ate the same amount of food – while experts would normally assume that people fasting over a restricted period of time would tend to take in fewer calories. None of the groups received any support in form of nutrition counseling.

All this probably led to the result that the people following the interval fasting method lost slightly more weight but also more muscular mass. The director of the study assumes that the reason for this is that the subjects ate less protein than the control group – simply because they were not forced to follow a well-balanced and healthy diet.

Another negative factor could have been the time the food was consumed. Some studies suggest that meals which are taken early in the day are metabolized more efficiently and that early meals cause the blood sugar and insulin levels to increase less than later meals. The subjects in the study skipped their breakfast. The team led by Ethan Weiss suggests that it is better to take a hearty breakfast instead of a sumptuous dinner “to avoid excess weight and to prevent blood sugar peaks.” This theory, however, must still be explored in more detail.

Our conclusion with regard to these studies

Don’t let studies and newspaper headlines cause irritation. Take a close look at the initial situation. First of all, all these studies have a different objective. Fasting purely to reduce overweight must be analyzed differently than fasting for health reasons – and what we look at is the second type of fasting. The 2020 study mentioned above was purely about losing weight among obese subjects. Nevertheless, we would like to point out that even the participants of this study reported on positive effects for their well-being: They felt fitter and more productive as the participants in the control group.

What is important though – and that is one of the conclusions we draw from the 2020 study – is that it’s not just about WHEN we eat but also about WHAT we eat. Simply restricting the time of day we take our food without reducing the calories or paying more attention to following a healthy diet will not do the trick for our body. On the contrary: This can lead to a reduction of our muscular mass. A balanced diet and taking in a sufficient amount of protein is enough to ensure that this is not a problem during interval fasting, even if you are an athlete.

In any case, all these “critical” studies have shown that interval fasting produces the same results with regard to losing weight as normal fasting and that there are no adverse effects. And that is something we believe is pretty positive! Because, as we noted in the first part of our blog on fasting, interval fasting is usually easier to follow through for people unexperienced in fasting, making it a more simple and yet effective way of fasting.

Why it is definitely worth trying interval fasting

We would like to point out here that all of these studies – as mentioned before – do not look at the effect of intermittent fasting on our metabolism. Depriving ourselves of food does something to our metabolism: it lowers the insulin level in our body and controls our appetite. Our body usually takes carbohydrates as a quick source of energy. When sugar is burnt in our body, free radicals are released which can cause damage to our cells. When fasting, our body uses the ketones produced during the decomposition of fat for generating the energy we need. Unlike glucose, ketones do not affect the blood sugar level which ensures that our insulin level remains constant. If you want to refresh your knowledge about this process, click here.

Furthermore, having longer interruptions between two meals during interval fasting has an effect on the metabolism of our cells. Since they are not fed from external sources, they search for alternative energy sources and start decomposing their own damaged reserves – which stimulates the autophagy process. This could be regarded as a natural emergency system for periods of famine which our body luckily uses simultaneously as an essential cleaning and renewal process for our cells: damaged organelles are decomposed and removed while undamaged cell components are recycled.

Is fasting something we naturally do?

This brings us to the last item on our pro fasting list: Another theory indicates that our bodies are made for fasting from a purely evolutionary point of view! For examining this point, let’s venture back in time and look at how life was a few centuries ago when three fixed meals per day and a couple of snacks in between were something that most people could not even dream of. Our predecessors were forced to compensate short or long interruptions between meals when hunters and gatherers were not successful in providing something to eat. For them, intermittent fasting was something quite normal and part of everyday life.

Because our body consistently faced such periods of stress, it had to adapt. And instead of simply coping with the situation, it was clever enough to take advantage of such interruptions to carry out some maintenance: increased expression of antioxidant defenses, DNA repair, quality control of proteins, mitochondrial biogenesis and reduction of inflammations.

What is more, is that food supply required a certain physical effort those days. The result is that even today our metabolism and our digestive system are geared at a constant alternation of phases in which we eat and phases in which we don’t eat mixed with physical movement.

These are all arguments for reasoning for the positive effects of intermittent fasting on our body, our health and first and foremost the health of our cells. And, at least for us, these are enough good reasons FOR interval fasting.


Those who are not capable of fasting because of health issues, time constraints or personal reasons, or anyone who simply no longer feels up to the challenge after several weeks of fasting can, of course, opt for a simple solution to achieve the positive effects of fasting on cell cleaning and renewal: by choosing spermidineLIFE®. Because, combined with zinc, it has an effect on cell division, contributes to normal DNA and protein synthesis and protects the cells against oxidative stress. And, of course, you can use spermidineLIFE® to provide your cells with that extra support for cell cleaning while you are fasting.

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