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I have read about and tried intermittent fasting in the past few months with some great results. The only hiccup was getting sick for about 3 weeks and losing that will to continue with it, until I restarted it recently. I was wondering what others experience were with intermittent fasting and also any recommendation of websites, books, research, etc on the subject. My personal experience is that when I am fasting I actually feel better and seem to be a bit more engergized. I even feel more energy when I workout in a fasted state.
-rich

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closed as primarily opinion-based by Baarn, Matt Chan Sep 5 '13 at 1:45

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise.If this question can be reworded to fit the rules in the help center, please edit the question.

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I recommend adding a specific question, this is likely to be closed as too open-ended. See fitness.stackexchange.com/questions/703/… –  J. Winchester Mar 11 '11 at 7:04
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Yes it is a bit open ended but mostly I wanted references to review about intermittent fasting. I was hoping to get different point of views that I could research. –  Richard Fantozzi Mar 11 '11 at 19:23
    
Great information from Dr. Weil on the subject –  Aaron McIver Aug 7 '12 at 4:32
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3 Answers 3

http://www.leangains.com/

This is the site of Martin Berkhan, who is a guy who has based his entire coaching on the concept of intermittent fasting. He is a Swede, but the site is in English. It's quite a large repository of info, and it includes a bunch of before / after testimonies from some of his clients.

Personally, I've had very good results with the Leangains approach of a 16hr fast each day, combined with a paleo diet. I've dropped at least one pant size in the first 2 - 3 weeks. I don't know how much of that is due to the paleo or the IF. I try to do some walking or short, intense exercise while fasted (it wouldn't be a good idea to do a metabolic conditioning type of training as those require a lot of glucose and you could end up in glucose deficit.)

Alternatively, Tim Ferriss advocates a protein fast once a week, to trigger autophagy and other cell renewal mechanisms.

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Why the -1 vote? I.F. might or not be a good idea, but my answer is an adequate response to the question asked. –  JDelage Mar 9 '11 at 11:41
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This is a bad response, because "It may not be a good idea" –  KronoS Mar 9 '11 at 15:35
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Hmm. A paleo diet may be a bad idea? Or intermittent fasting may be a bad idea? Pretty vague comments. I'd be curious if there is actual science behind the claim that "this isn't generally good advice." +1 to get you out of the hole –  J. Winchester Mar 11 '11 at 7:02
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If fasting 8-12 hours at night is normal for pretty much everybody on the planet, how does 16 hours of it cause "undue stress?" Doing 50 pushups, sprinting up the stairs or running 10k also cause stress, but we recognize these stresses stimulate our bodies to grow stronger. Aside from that, the question asked for references about intermittent fasting, and a legitimate answer got downvoted with no explanation because somebody thinks intermittent fasting is a bad idea? That's not what I want this site to become. What's next, downvoting answers about vegetables because I don't like them? –  J. Winchester Mar 16 '11 at 23:20
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Grazing is good for food companies. So remember: eat 10 times a day or you will get fat and ugly! –  gruszczy Nov 29 '11 at 10:52
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Fasting for an extended period of time (usually more than 3 days) places your body into a state of ketosis, and you begin burning any excess fat on your body. If you are overweight and have fat that you can safely lose (safe is relative, but definitely over 3% body fat), then fasting will not hurt you as long as you get plenty of liquids. (see my answer to "At what point do I start to burn muscle on a calorie deficit diet?"

That being said, if you fast for 3 days and then eat like a pig for 3 days, you're going to do yourself some serious harm. There are no known benefits to intermittent fasting exceeding the benefits of simple calorie reduction. If you're looking to lose weight, restrict your calories first.

Personally, I'm a big fan of the Atkins diet. It places your body into the same state of ketosis as fasting, but you still get to eat as well. Even with Atkins though, you will still gain or maintain your weight if you eat too many calories. Atkins is safe while you are sick under most circumstances. Fasting can be seriously detrimental while you are sick if not done properly.

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"if you fast for 3 days and then eat like a pig for 3 days, you're going to do yourself some serious harm" Do you have evidence for this? Since I.F. eaters dont necessarily eat fewer calories overall, there has to be some heavy eating going on during the non-fasting periods. –  J. Winchester Mar 11 '11 at 7:00
    
You don't need to fast for three days to be in ketosis. In fact, you don't need to fast at all to be in ketosis. Ketosis means that your body is using fat rather than ingested glucose. It enters this stage if you don't ingest enough gucose. So any sufficiently low carb diet will eventually induce ketosis - even if you're eating plenty of proteins and fats. –  JDelage Mar 11 '11 at 8:51
    
@JDelage - I understand that, however, most people ingest enough carbs that it takes about three days for their bodies to flush them all out. –  Nathan Wheeler Mar 11 '11 at 13:42
    
@J. Winchester - Overeating (once) sends excess blood to your digestive tract to successfully carry away and store all the calories, vitamins, and nutrients that you've consumed. Just the first time you overeat, your triglyceride levels begin to climb. All of this increases the levels of stress on your body, and it's the same reason you shouldn't take all your vitamins at once if you can do otherwise. –  Nathan Wheeler Mar 11 '11 at 13:56
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I just read this about the purported benefits of intermittent fasting.

http://www.bbc.co.uk/news/health-19112549

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We're looking for long answers that provide some explanation and context. Don't just give a one-line answer; explain why your answer is right, ideally with citations. Answers that don't include explanations may be removed.

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Can you elaborate on the article further and summarize and quote its main points here? A link by itself is a nice reference, but will lose its value if the content changes or the link disappears. Consider editing your post accordingly. –  Matt Chan Aug 7 '12 at 11:52
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