Study: Fasting Helps the Immune System

I think this study is interesting:
Fasting triggers stem cell regeneration of damaged, old immune system

In the first evidence of a natural intervention triggering stem cell-based regeneration of an organ or system, a study shows that cycles of prolonged fasting not only protect against immune system damage -- a major side effect of chemotherapy -- but also induce immune system regeneration, shifting stem cells from a dormant state to a state of self-renewal.


The study has major implications for healthier aging, in which immune system decline contributes to increased susceptibility to disease as we age. By outlining how prolonged fasting cycles -- periods of no food for two to four days at a time over the course of six months -- kill older and damaged immune cells and generate new ones, the research also has implications for chemotherapy tolerance and for those with a wide range of immune system deficiencies, including autoimmunity disorders.

I’m hoping that I can get access to the study at UC Berkeley to see how often the subjects were fasting. I’d like to try it.

After a day or so, you don’t even feel hungry anymore.

I’ve done several months where I just didn’t eat anything on Sundays, and have done pretty much a year of fasting 18-20 hours a day. I would recommend starting with make a last meal at 4-6pm, then don’t eat until 6-10pm the next day. There you go, 24-30 hours of fasting. Coffee apparently helps some people with hunger. I never really felt it.


Actually, just yesterday I started a new plan of eating. For lunch 12-1 just drink a homemade juice(carrots, apples, beets, greens, reds, etc…) and/or oatmeal with milk. The eat a huge meal for dinner at 6-7.


Interesting… I skip meals often, but it’s usually by accident. I’ve been mostly disciplined about eating on time over the last week, but it takes a lot of effort. :slight_smile:

I’ll experiment with it…

Hi Josh,

This is really interesting because it is stated in the bible that Jesus pasted for fourty days and nights to strenghten his self. because of that action most of our great seekers and sages like Buddha; Mahatma Gandhi; Dalai lama and others doing the same thing.

That might be the reason they are so discipline in anything. according to the scriptures that Fasting is often associated with prayer. In Ezra 8:15-36 one can read of an account where there was a request made for God to grant a safe journey and the people not only prayed to God they also refrained from eating for an allotted duration.fasting

further, Matthew 6:16-18 says, “when you fast, do not look gloomy like the hypocrites, for they disfigure their faces that their fasting may be seen by others. Truly, I say to you, they have received their reward. But when you fast, anoint your head and wash your face, that your fasting may not be seen by others but by your Father who is in secret. And your Father who sees in secret will reward you.” The thrust of verses 16-18 is that God will know the situation of the one who is choosing to fast; and thus, there should be no reason to act gloomy, or walk around in sorrow, but rather to “wash up” and not appear to the world to be fasting.

On the other hand, The process of ketosis is one of the physiological effects of fasting in which the brain (and some other bodily processes) uses ketones produced from fatty tissues as a fuel instead of the usual glucose. This is called “muscle sparing”.

When glucose isn’t readily available via the diet (in the form of carbohydrates) and the glycogen stores in the liver become depleted, the body could break down muscle to get it. But ketosis is an adaptation that will spare muscle during times of shortage by instead breaking down fat stores and manufacturing ketones for brain fuel. It is said this state is attained at approximately 48 hours of a water fast for women and closer to 72 hours for men.

The effects of fasting ketosis have become a more popular and controversial subject in recent years due to low-carb, high-protein dieters relying on it long-term to “burn the fat”.

Where ketosis was once considered a “crisis response” of the body and fine only for short durations, there are some doctors who now contend ketones are an acceptable alternative fuel, produced and used by the body any time glucose is scarce, which can happen even in non-fasting, non-dieting individuals, such as during intense exercise or during sleep. They are considering it a natural metabolic process where ketone production and use fluctuates constantly in response to the body’s needs.

What is so controversial about the low-carbers use of ketosis is the long term, artificially produced, use of it. Over long periods of time, their high-protein diet produces excess protein by-products that become a strain on the kidneys to eliminate. Ketosis also creates a mild acidosis of the blood, which, over a long period of time is considered detrimental to our health. One effect being the leaching of minerals from our bones, causing osteoporosis.



Michael Angelo

I didn’t read this article yet, but it has some information on fasting in it, including a mention of learning and memory: Running on Empty

Regularly taking breaks from eating—for hours or days—can trigger changes both expected, such as in metabolic dynamics and inflammation, and surprising, as in immune system function and cancer progression.

I ended up heavily experimenting with fasting over the past year and a half, doing water fasting for 2-5 days at a time. Also a lot of experimentation with caloric restriction and alternate fasting. I found that alternate fasting (switching from eating to fasting at 4 pm every day) made me feel better, but I begin to feel very strange after about a week or two and wasn’t sure if it was healthy, so I’ve only tried that twice. If I could figure out how to avoid those side effects, I would try it again.

The following USC link has the same date as your quoted study (June 5, 2014). It mentions the same fasting interval: two to four days, over six months.

Following link (2016) says a “fasting-like diet turns the immune system against cancer”.

Following link (2017) says “a short-term fast appears to counteract increases in blood sugar caused by common cancer drugs, protecting healthy cells in mice from becoming too vulnerable to chemotherapy”:


That first link that you posted is what got me started last year. I’ll probably start the next fast a week from tomorrow. I’m still working on an “extreme salad” experiment. :slight_smile:

Best of luck :slight_smile:

Thanks for starting this thread. I have several female relatives who are at various stages of cancer treatment. They all say they’re going to have a go.


I found it very difficult at first. I think that drinking lots of water helped with later fasts. I was aiming for a gallon a day, though don’t remember if I drank that much.

The book Fasting and Eating for Health by Joel Fuhrman might also be worth checking out, mainly for the studies that are cited. I got a lot of ideas about my current diet from there (though I eat fish + olive oil, and he is vegan and doesn’t eat oils, iirc).

This microbiome research is also interesting.

Hope that it helps.