Towards More Rigor in the Use of Fasting as a Therapy

Fasting produces benefits to health that are meaningful in comparison to the cost of this intervention - it is free, and the health benefits are reliable and repeatable. When it comes to improved metabolism and long-term health benefits, no medical technology is yet established to do better than the practice of intermittent fasting or calorie restriction in people without severe medical conditions. Senolytic therapies should hopefully greatly improve on this performance in older individuals, but that data has yet to emerge. As researchers point out here, fasting is not usually rigorously applied in medical practice. There are groups working on approaches, for example the fasting mimicking diet that is intended to set a standard for how to apply reduced calorie intake as a therapy. But more generally, much work is left to accomplish if fasting is to be integrated into medical practice in the same way as pharmacological approaches have been.

Recently, fasting has become one of the most compelling topics of the Nutrition Era. In the last five years, interest has passed from the Mediterranean to the Ketogenic Era, including the concept of caloric restriction and 'only water' fasting. Recently, research in animal models and humans has highlighted the potential health-promoting physiological responses to fasting including ketogenesis, hormone modulation, reduced oxidative stress and inflammation, and increased stress resistance, lipolysis, and autophagy. Although the panorama of evidence on fasting and caloric restriction is wide, there is a lack of a correct and safe fasting protocol to guide nutritionists and physicians in its application.

The act of fasting gained an increased focus in the scientific panorama thanks to several pieces of research developed around 30 years ago. The first studies referred to minor organisms and not directly to humans, because fasting and caloric restriction were considered tough interventions, combined with health risks if not adequately structured. Initially, studies on yeasts and murine models brought remarkably interesting results, later to be replicated in humans.

Some people, to be committed to their health, try adopting new habits as nutritional styles change. Nowadays, people are motivated by information from various sources: media, social networks, doctors, gyms, health coaches, and, simply, word of mouth and rumor. The accumulated information is not in line with scientific discoveries and safety protocols. Mere abstinence from food cannot result in efficacy if it is not well contextualized within a structured nutritional intervention. Fasting improves blood biomarkers for metabolic health, stress resistance, and suppresses inflammation. For example, most Westerners emulate their idols, picking up a fasting model that is supposed to help with losing and sustaining weight, keeping mentally sharp, and promoting longevity. Most of the time they do not experience the suggested benefits because of an unbalanced diet.

In the light of the above, the goal of our paper is to examine the context in which fasting could be practiced, and the most important discoveries in fasting used in pathological conditions such as chronic degenerative diseases. Moreover, it aims to offer to clinical experts in nutrition a specific guide to be consulted and personalized for each patient.



Yeah, it sucks we are on our own, but my suspicion is any assistance wouldn't be worth the oppression and negative attention it would bring. This is still something we can do in private.

The 4 day water fasts are becoming easier over time, and so adding a puke-worthy 5 grams of fisetin to a glass of water twice a day brings back the old "God, I hate doing this." feeling of the first few months. As I chug it as fast as possible, I always think "The wages of sin is death" and it makes me feel better....then quickly go wash out my mouth.

Posted by: Thomas Mark Schaefer at June 22nd, 2021 11:05 AM

I'm wondering whether long regular water fastings (let's say one 3 weeks water fasting every year) can destroy some percentage of senescence cells and act like Senolytics drugs?
My logic in this matter is following - when we are fasting, our body is losing its weight, appropriately 10 - 15 % of its weight. I guess it happens particularly because our body eats itself but eats its own weak cells in the first instance, mostly its weak senescent cells.
Normally after a fasting our body gains its original weight again. So the body renews its own cells, by eliminating its senescent cells. Dear fellows, what do you think?

Posted by: Alek Ales at June 22nd, 2021 2:21 PM

Sorry, I forgot to determine the "water fasting". The water fasting is when we drink only water during the fast and nothing else. So, during a 3 weeks water fast we drink only water and eat NOTHING, even don't take any medicine. And only after 3 weeks we start slowly drinking juice and then taking very carefully food. I know there are many types of Fastings, but my question above was about only the water fasting, and not about any another kind of calorie restrictions. Thank you.

Posted by: Alek Ales at June 22nd, 2021 2:43 PM


"Intermittent fasting is also a promising intervention for the targeting of senescent cells. "Zombie" cells don't respond well to being starved of sugar (sugar = brains!!) for long periods of time. Intermittent fasting has been shown in animal models to promote autophagy, or cellular "self-eating" that helps clear out damaged cellular components including mis-folded proteins."

And here is a video about fasting as a senolytic

Posted by: august33 at June 22nd, 2021 9:25 PM

I do Valter Longo's Intermittent Fasting. Should i take my Senolytics after the last day of the fast? Or during days 3,4,5?

Posted by: John at April 16th, 2022 11:33 AM


My favorite theory is that during fast some of the presenescent cells will be morphed back to "good" ones. Some will be destroyed. So it could mean that there's a specific cell population which is brought back from senescence but is prone to "fall from grace" again.

With this in mind I would (and actually do) take fisetin before fasting in order to clean as much of already senescent cells and the fasting will repair the rest. Of course, all this is not based on hard experimental evidence.

Posted by: Cuberat at April 17th, 2022 5:23 PM
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