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by foxyv 2330 days ago
Lately I've been doing 7 day fasts two times a year mostly to reduce visceral fat and reduce my chance of type 2 diabetes. However a lot of science is pointing to it being a good way to reduce cancer risk. Nothing definitive, but it's nice to think I may be helping my body fight possible cancer too. Maybe I will catch some of these things early during these phases where the genes are present but the cancer hasn't begun to be diagnosable or slow it down.

I've also heard some doctors suggest that fasting during cancer treatment improves the effectiveness of chemotherapy.

4 comments

7 days fasting (electrolytes-only) gives me a week-long euphoria afterwards, but days 6-7 show some ugly symptoms of previous diseases, so persevering those is a bit tricky. It also leads to 10-12lb weight loss.
Lately I've been trying supplementation of potassium, magnesium and calcium which are supposedly lost during a fast. (I'm skeptical of most supplementation...) Pretty much just sea salt, creme de tartar, and lime juice. Seems to help a little with the weirder effects of a long fast. (Cramping, weakness, lightheadedness) In water they taste a little like gatorade without the sugar.
The electrolytes I use are some kind of salt combined with the elements you mentioned; without proper electrolytes you might die during longer fasts. I avoid any kind of juice to make sure that part of my digestive tract can rest and do some internal cleanup. Autophagy should start at around day 5 and immunity renewal at around day 3.

If I do sauna (many hot/cold cycles), I feel great for a day, if I do a 7-day fasting, I feel like that for a week. Sauna probably forces some mild cleanup through sweating, fasting through autophagy and burning off fat that stores toxins body didn't want to deal with earlier.

Can you share your exact recipe? I'd be curious what you're doing for magnesium and calcium. How about zinc?

Problem is a lot of those electrolyes can cause dihreah especially on an empty stomach.

Google snake diet - he has a mix.
Hmm, this seems dangerous or maybe unique to each individual.

In the past I've had low blood sugar issues (started shaking and got splitting headache) because I forgot to eat for 24h or so and worked long hours, it wasn't a nice experience and I most certainly wouldn't want to repeat that on purpose by fasting. In addition to that, I often "bonk" on longer bike rides (don't eat sufficiently) and do intensive cardio exercise 6 hours a week. I have a BMI around 22 (used to be lower but hey, I'm not getting any younger..).

So do you think this is something anyone can/should engage in? How do you decide if your body can safely engage in multiday fasting like that?

I don't know frankly. I was surprised it was so easy for me, but let's say first day I get headaches which I attribute to caffeine/sugar withdrawal, maybe that's your case as well. Drinking 1 liter of water quickly often resolves that though. It's possible you are actually dehydrated as most water comes from food and not drinks, so if you continue drinking like you are used to, you end up with insufficient water.
Just drinking water can lead to electrolyte imbalance or is am I mistaken?
You are completely right. If you scroll up 3 posts you'll see I mentioned "electrolytes-only".
what kind of activities do you do during the fast ? normal work life or retreat / reading ?
First 3 days normal stuff including intense HIIT training, then I try to relax in my spare time for the remaining 4 days (normal business). On the first day I might suffer from a slight headache if I was used to a lot of caffeine/sugar. On the second day I am the "smelliest", so it's best to have that one over the weekend when I don't have to be around other people.
> On the second day I am the "smelliest", so it's best to have that one over the weekend when I don't have to be around other people.

I've never done a 7 day fast and before I do I'd like to be better informed. What do you mean when you say the smelliest? What does it smell like? Is there some kind of smell throughout the fast? Thank you

Smell is like when you don't wash yourself for a week, quite unpleasant. It's gone on day 3, but on day 2 I am rather staying alone. Then from day 3 you might suffer from bad breath due to ketosis, regular oral hygiene is important when around other people.
Wow. I haven't not washed myself for a week but I imagine. Does showering more frequently help? I heard about the oral hygiene during the fast before. I am basically interested in doing a fast like this but am not sure if I could go to work if I smell unpleasantly but as you said I could probably start in such a way that the 2nd and 3rd days fall on a weekend. Thanks again!
HIIT + fast .. that's a first. How old are you ? 20 ?
I wanted to know myself better, how much I can do and if fasting affects my athletic performance. I did my 3x full-effort HIIT in a row each day and even went climbing steep mountains on a bike on days 2-3 during my first 3 day electrolytes-only fast. The second climb I had to abort in the middle of the climb due to "losing vision", i.e. I perceived my vision was deteriorating in an all-out effort (like when you overdo it with HIIT).

I read some study mentioning that HIIT during fasting helps to keep muscles from breaking down as muscles start being utilized at around day 4 to synthesize glycogen from proteins once liver storage is depleted, so I keep doing it, though days 4-7 only one series a day.

What do you consume during this time? How do you know it's safe? I'd like to try this sometime. Do you have any advice?
First, try just 1-2 days but remove all caffeine/sugar like a week ahead. Once you can do 1-2 days without any major problems, try doing 3 days (Friday + weekend). Once you are fine with that, try 5-7 days, water + electrolytes only, no food, no juice; drink however as much as you want, if you feel weird, drink more (always with electrolytes). If something really feels off, have some energy bars ready to intervene and break fast quickly and safely. Also, check yourself for diagnoses that might respond badly to fasting and in that case avoid doing it.
Thank you for this. Can you comment as to why you think it's necessary to remove all caffeine and sugar in advance? The reason I ask is that I have a penchant for black coffee and imagine that it's useful as an appetite suppressant.
Because you might have nasty withdrawal effects like strong headache on the first evening that could persuade you to break the fast immediately. You can gradually tone down your coffee intake so that at the beginning of the fast you won't have those effects.
Can you safely fast if you rely on medication?
Discuss this with your physician. People who have e.g. problems with kidneys should not fast.
I've only done 3-days and not 7, but for n=1:

- make sure to consume salt (adding to water is the easiest); if anything, err on the side of both too much water, and too much salt (we normally consume a lot of both through food).

- Some people still consume certain zero-calorie items, like black coffee, green tea, or bone broth. You still get most of the fasting benefits, and it might be a good way to start (bone broth with added salt is a great way to keep electrolytes up, and fill your stomach).

- I experienced a bit of back pain; apparently muscle pains are common, especially with new fasters. Accounts vary on this being evidence of "detox", or a side effect of mineral deficiency; but supplementing minerals in water probably couldn't hurt.

- Dr. Jason Fung is a great resource: https://www.youtube.com/watch?v=tIuj-oMN-Fk

- You'll find it odd that you don't know what to do during mealtimes. :) Have a plan for another way to take a break during lunchtime, etc.

- Optional: it's vastly easier if you start already in ketosis (IF and/or low-carb)

Bone broth has calories.
A lot of that loss is water weight, though.
Yes, but that stops at around day 5 and you can always drink a lot to compensate for it.
> show some ugly symptoms of previous diseases

This could be your body breaking apart old injuries to start repairing them better.

I can't really tell, I had 4 symptoms of past problems suddenly escalating on day 6 last time I took the fast, and since then I never experienced them again (so far), so there might be something interesting going on. It's possible autophagy and fat burning might remove some "memory" but I have no scientific explanation for it. My theory is that as body doesn't have to fight all kinds of pathogens coming in from food, it can start correcting internal problems/mistakes instead with the same processes it normally uses to fight external threats.
Breaking apart old injuries...? Never heard of this hypothesis, how would this work?
Many people report feeling older injuries/illnesses during prolonged fasting. It's not clear what is the nature of that, if it's just psychosomatic and some neural pathway is correcting/readjusting/"backpropagating" itself (think phantom pain) or if the original repair was "temporary" and body does a proper rebuild there, or something completely different is going on. Try 1 week then tell us if you felt something similar, I did.

EDIT: This Reddit thread has interesting comments, elevated HGH might be the culprit:

https://old.reddit.com/r/fasting/comments/5gl1aq/can_fasting...

> days 6-7 show some ugly symptoms of previous diseases

Could you describe this? I'm not sure what it means.

I started to feel some past problems in e.g. neck area from some botched gym exercises, inside head where I had often sinusitis problems, some left leg issues etc. They seemed to escalate quite a bit, to the point of pain, I was on the verge of breaking the fast but I kept going, then on day 7 all those symptoms disappeared and I haven't experienced them since my last long fast. Not sure if they were of physical or neural (memory?) origin.
Actually, this is quite cool, after 5 days of fasting human growth hormone jumps to 10-20x normal level and that corresponds to me feeling miserable on the 6th day, then again great on 7th. It's now starting to make sense why some physical injuries were felt and then disappeared.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC329619/

Yeah their is some research that suggests this. I think there are some clinical trials to test this as well. The hypothesis is that when you are fasting your cells go into a rest and repair mode vs growth mode. Cancer cells theoretically don't do this so that may activate an immunological response. This conflates with the idea that chemo would be more effective is that the drugs would be taken up by cancer cells b/c they are actively growing vs the regular cells. So maybe less side effects and maybe more drug available to the cancer cells. I don't think we know for sure.
Steve Jobs fasted often and ate a very limited diet, cancer still got him.
That reminds me of people who follow the Calorie Restriction Optimal Nutrition (CRON) diet. Only they practically starve themselves everyday. I know it's not the goal they do try to consume on the absolute necessary nutrients.

My theory is someday CRON will surpass veganism merely for one-up-manship.

Veganism is mostly about reducing animal suffering. It also has a health angle but it's mostly about the ethics of killing animals when we can have a complete and healthy diet eating plant-based (plus fungi).
I know what veganism is but it's promoted by its followers as healthy when in reality it's based on dogma.

Anyone can choose what diet they want. Vegetarianism is just as good but it seems to be too tame for some people. It strikes me that many follow veganism merely as one-up-manship, posturing, or due to intimidation.