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Fasting impact on immune system



Study finds fasting for 72 hours regenerates the entire immune system

This is a nice summary of what has been reported before. The key take away for me is that fasting induces stem cell regeneration of the immune system. This means quiescent stem cells start dividing including leukemic ones. Only when leukemic stem cells divide are they susceptible to a TKI drug.

I have done several 3 day fasts so far - about to start a new one to end Lent. I have a suspicion that fasting for three days several times a year will go a long way to added health. It's like a reset for the body. The first time you do this it is very difficult. Salt intake is very important during absence of food. But once you succeed, your body has produced - probably for the first time in your life, key enzymes necessary for fat mobilization and energy production (ketones). Once established, fasting on a regular basis is easy ... you already have the building blocks.

An interesting side note - populations that have experienced starvation and survived show a dramatically increased life span. Many live to be over 100. I have a thought that it is due to the "fasting" immune response (in this case forced fasting against their will).

I wonder - truly wonder - what would have happened to my CML prior to diagnosis when my white blood cells were over 35,000 and I did a 3 day fast first. Imagine a clinical trial in which patients are first put on a fast at diagnosis of CML to learn what the body does to CML. There is no research I can find that has anything reported on this.

Hello, how are you? I decided to do the 72-h fast on my own, taking advantage of the Lent, I'm at Nilotinib 600 per day in two doses every 12 hours, can you give me some advice? I am in RMM PCR 0.022 to 9 months of treatments. On April 22, I have my monthly follow-up blood count
Thank you

The first time is the toughest because your body has never had to produce the enzymes needed for energy before. This requires 12 - 36 hours ramp up time. During this phase of the fast, your carbohydrate level is used up and leads to fatigue, possible headache and intense hunger. It's very important to drink plenty of water. Also add some electrolytes (I use Himalayan salt) to your first glass in the morning and at night. Salt helps a great deal. I also take extra magnesium (~ 400 mg per day).

After the first day, assuming you are still somewhat active (walking, etc.), your body will begin to convert fat into ketones for energy. Buy Ketone strips at the local chemist or pharmacy so you can determine when this happens. You'll be surprised how long it takes with no food before ketones show up. Ketone burning is when autophagy and other cell cleaning takes place.

Sometime during day two, you will feel very good and hunger decreases dramatically. You will feel much more 'aware' and energy returns. The energy returning is simply because your fat is now converting easily to ketones and the process is set up and working. You will have plenty of energy - as long as you have fat on your body (which most of us do!). Your body is in ketosis at this point.

On the third day of the fast, major benefits occur. White cell count is reduced as your body scavenges old cells for "parts". This scavenging of white blood cells is what sets the stage for stem cell rejuvenation once you begin to eat again. Stem cells in bone marrow (and elsewhere) mobilize and come out of quiescence. And stem cells in other parts of the body get busy as well.

On the fourth day (or end third day), break your fast with some bone broth or a very light meal to give your digestive system, which has been resting, a chance to ramp back up. I'll typically eat some nuts (almonds). If you keep carbohydrate intake to less than 30 grams, you will likely remain in Ketosis (test strips confirm) and autophagy continues. I tend to stay in ketosis 5 days out of 7...On weekends I enjoy most any food - except sugar.

Once you begin eating, signals are sent to your bone marrow to replace all of the lost cells and your immune system is regenerated and rejuvenated.

Continue to take your Nilotinib as you would normally.

(My own personal theory is that when CML stem cells are signaled to divide, the presence of our TKI kills them, reducing CML stem cell numbers. During a fast, this is probably the single largest opportunity for massive LSC death to occur - triggered by fasting. Fasting alone puts stress on LSC's and may have prevented my CML in the first place, but having TKI present insures their death. That is the theory. I am PCRU, so I don't have any evidence personally that this works. Just that the science behind fasting and the research is very compelling. And - I feel better, lost a few pounds, joints are healthier and no chance for diabetes to occur.)

Thank you very much for the information, I follow your posts always very informative. I will do my PCR in the month of June approximately, do you think I should do the fast now or just before doing the pcr?

Better to do the fast sooner rather than later so by the time your PCR is taken, your blood system has had time to rejuvenate. During a fast and for a time after, your blood markers are skewed (cholesterol will go up a bit and then drop, WBC's are lowered, and other markers are shifted). You don't want these temporary effects to show up in any blood test. It could confuse your doctor. Also - any bcr-abl protein (CML) produced prior to the fast will have had a chance to diminish. This is the experiment - that bcr-abl is greatly reduced because LSC's and daughter CML cells are greatly reduced in number beyond what Nilotinib was accomplishing.

Also - listen to your body as you start the fast. The first day is pretty easy except for the hunger you will feel by afternoon of the first day. That hunger is very impressive. The first time I tried a three day fast, my heart started to race on the second day and I stopped the fast. What happened is I was dehydrated and lack of salt. The next time I tried, I was more aware and avoided all of that. Here's additional info.

Please keep us posted on your journey especially how you feel during the fast. Also - when you do get your PCR taken, it will be very useful to learn whether your PCR dropped significantly from your last test (i.e. < 0.01%). Keep in mind that if your PCR does drop a great deal following your fast, it is anecdotal evidence not scientific, but still very encouraging.  Only a true clinical trial could verify whether fasting coupled with TKI can significantly impact CML stem cells potentially leading to successful treatment free remission. But the science is compelling to me regardless.

Hey Scuba! Thanks for your insight on this. The month of Ramadhan (fasting month for Muslims) is a few weeks away & my friend who has CML will be trying his best to fast throughout the month. He is on Nilotinib & his PCR is at 0.7% & his next PCR test will be in June, which is a month after fasting. Will be interesting to know his BCR-ABL counts & will keep you posted. 

Hi scuba,
Some thoughts on 40 hrs fasting+moderate exercise.

I have done many 40 hour fasts. It is great for metabolic restoration (prevents diabetes type 2) and weight management, but probably of no use for stem cells in terms of CML. The body needs time to work through its carbohydrate stores (glycogen) and that takes about 40 hours of no eating. So just when you would begin to enter autophagy (process of old cell breakdown), you begin eating again. Body never gets to reset.

The studies I posted suggest a full 3 days is needed - perhaps even longer for some people. A sure way to know is when you enter ketosis (as indicated by ketone sticks) at the moderate level. From that moment on you are in autophagy (cell renewal).

(note: intense aerobic exercise like sprinting for 20 minutes (on/off sprints) or any other high intensity workout (20 minutes) can burn through carbohydrates quickly and put you into ketosis much sooner, but still there are not enough hours left in 40 hours to benefit much. Although some autophagy will have started following intense exercise.)

I am going to try 40+hours fast.
Thanks Scuba for great information

Great link - here is an additional one cited in the article:

There is no doubt in my mind that fasting coupled with an alternating ketosis, non-ketosis metabolism can have profound effects on preventing cancer, increase longevity and facilitate overall better health.

What I have learned is that our bodies actually need long periods (3 days) of not eating during which the body 'cleans house' and recycles old cellular material. It is as if the body is preparing for new incoming (like selling your old furniture in order to make room for new and better furniture) building materials to replace the old ones. Once fasting has gone on long enough (ketosis in full vigor for a few days) and you begin to re-feed (including adding carbs), the body quickly rebuilds what it has lost and prepares for the next "no food" period. This switching back and forth is normal and healthy.

In our modern diets, we have perfected the art of never going without food. It turns out this is bad for our health. Going without food is necessary for health.

My own approach has been to become seasonal in how I eat. Normal fruits and carbs during spring (northern hemisphere) when fresh carbs are growing normally available and then switching to fats when spring is over combined with periods (3 times per year) of 3 day fasting.

I can tell you once your body has acclimated to a ketosis based metabolism the first time, you can do this during the year easily - because hormones and enzymes necessary to switch between carb fueled or fat fueled are established and balanced. It is that first time which is hardest because ketosis based enzymes and hormones are practically non-existent - you haven't needed them.

Ketosis, non-ketosis is the normal way to live.


Hello, first attempt of fasting failed, I only achieve 48 hours of fasting, I hope it works for something, I felt very tired this morning and I had no strength and some dizziness, I had to suspend the fast, next month I will try to go for 72 hours .
Thank you

Hi Damian,

First time is tough. What helps is drinking Himalayan salt water (1/4 teaspoon in an 8 oz. glass) first thing in the morning and then again in the afternoon. All other times need to drink plain water to stay hydrated. Check for ketones using a ketone strip. Only when your body is producing ketones (mid-scale typically shown on the strips), is your body coming out of low sugar fatigue and getting the benefit.

Next time you try and feel the need to end the fast, end it with nuts, olives, avocado or some cheese so you can stay in ketosis. Avoiding carbs will help get you into ketosis and feel much much better.

It does give you an idea of what our ancestors went through when there was no food. I found the experience enlightening.

Totally, I think I went into ketosis, I did not have to check it, but if I had strong breath with extreme tiredness and urinated a lot, I think if I was not there or I was very close. The next I'll do that, some broth or soup with some almonds. I ate some whole grain galetas when I suspended
Thanks again