I have been doing a lot of fasts during the years:
It rarely works for permanent weight reduction - mostly because when you are off the fast you don't have proper new eating habits ingrained.
It takes 3 days to forget about the hunger. After that you have a lot of energy for the next 2-3 days.
Your senses become extremely sharp - you see better, hear better, smell better.
The moment you have acetone in your breath is a good time to stop.
When you start eating - your digestive tract is really fast to evacuate for the first few times. Be at home. Avoid hard foods.
After the first week you may have problems with the blood pressure - stand slowly, take your time waking up - if the world becomes more colorful - lay down on the ground ASAP - you are on the way of passing out.
Sex during the fast is awesome - see the senses thing above - the orgasm is multiple times more intensive than usual.
The moment you get acetone breath is also a great moment to begin a ketogenic diet if you want to experiment with that diet as well. The acetone breath is probably a function of ketogenic metabolism, and if you've already engaged it, why not continue and see what a primarily fat-burning metabolism paradigm does for you.
Also, self control. <20g carbs a day is a whole different kind of diet based self control.
But the results from 30 days for me was fun, definitely worth a month as a body hack.
About 4 months was enough for me to drop right around 70lbs a couple of years ago.
Keto has a lot of cultists that think it's magic when it comes to weight loss. It's not; it's still fundamentally a caloric deficit diet for that purpose.
But it is a really interesting metabolic hack when you start doing some research into it. It's an absolutely fascinating testament to the adaptability of the human body and its ability to metabolize energy from other sources when the "cheap" energy it can get from carbohydrates is unavailable. There's a lot more going on than just burning fat when the body is in ketosis.
Ultimately, it's a bit too restrictive for me to stay on indefinitely, but the shift in mental state and energy level is beneficial enough for me to cycle on it a few times a year just because.
> it's still fundamentally a caloric deficit diet for that purpose
This is true. I think the misconception of magic comes from the illusion that you basically can eat until one becomes satiated. It is easier to become satiated and hunger is more infrequent.
I think a lot of it is the popularity of Gary Taubes and people not fully understanding what he means when he says that the calories in/out theory doesn't really explain obesity.
His actual argument is a bit more nuanced, but tends to get lost in the soundbite.
It's probably best to not do that, if you're looking to get more substantial benefits out of fasting.
In fact, what works really great is practicing some meditation while fasting - if you already have some experience with it. The calm, clarity and joy from both fasting and meditation amplify each other.
The association between fasting and meditation appears over and over again in many cultures, many places and historic periods, as people re-discovered the synergy between the two. But the classic recommendation is to abstain from "indulging" in sex, drugs, etc during the practice. YMMV.
I have fasted for 2 weeks. I think that for a young healthy human one week will rarely cause problems. But after the first week I was permanently cold on the inside (I am a person that never wears long sleeves or jacket even if it is -10 Celsius outside) so I said - enough for now.
Medical supervision - whatever makes you feel best - if you will be calmer with having someone check you daily go for it.
Fasting is something that is individual - I have had involuntarily fast lasting 72-96 hours while playing diablo. But I have friends that cannot get a single afternoon without food - they fainted.
A good test is 18 hour inteminent fast, then cut your teeth with 32 hour one (you eat dinner on Monday before going to bed and next meal is Wednesday breakfast) - if you feel anything than hunger and some psychological discomfort - maybe it is not for you.
> How long would you be comfortable fasting for without medical supervision?
One week if you don't have any major health issues.
Not even a day if you're suffering from some serious condition.
Plan for less physical activity than usual, but do not become a vegetable. Take some short walks, do some small work with your hands. Meditation is great during this time, but you have to be somewhat accustomed to it.
Restart eating step by step. Begin with some fruit juice or clear soup. Then graduate to very soft, almost overcooked rice or something like that. A vegetarian diet for the first few days is beneficial. The longer you're fasting, the more cautious you have to be with restarting your diet.
> The longer you're fasting, the more cautious you have to be with restarting your diet.
Do you have any experience on what happens if you don't? It certainly makes intuitive sense that you need to ease yourself back into "normalcy", but what are the potential risks that everyone is very explicit about trying to avoid?
> what are the potential risks that everyone is very explicit about trying to avoid?
http://en.wikipedia.org/wiki/Refeeding_syndrome (fluid disorders, neurologic, muscular and hematologic complications, gastrointestinal disturbances, can culminate in coma and cardiac arrhythmias or failure)
i'm guessing those things are heightened because your body thinks you're starving to death, so it amps the food-seeking abilities (senses) and reproduction incentives (sexual pleasure) to 11.
Fasting spikes stress hormones and lean tissue catabolism. It's clearly a very stressful thing for the body. Small doses of stress have hormetic benefits but it's easy to go too far.
Vigourous exercise is stressful, too. A bit is good for you, but a lot is clearly bad. High energy expenditure athletes prematurely age and have elevated death rates. I'm sure it's the same with fasting. I would be careful about doing "a lot" of fasts.
It rarely works for permanent weight reduction - mostly because when you are off the fast you don't have proper new eating habits ingrained.
It takes 3 days to forget about the hunger. After that you have a lot of energy for the next 2-3 days.
Your senses become extremely sharp - you see better, hear better, smell better.
The moment you have acetone in your breath is a good time to stop.
When you start eating - your digestive tract is really fast to evacuate for the first few times. Be at home. Avoid hard foods.
After the first week you may have problems with the blood pressure - stand slowly, take your time waking up - if the world becomes more colorful - lay down on the ground ASAP - you are on the way of passing out.
Sex during the fast is awesome - see the senses thing above - the orgasm is multiple times more intensive than usual.