Remembering Kevin Moore

My Thoughts And Analysis About My First-Ever One-Week Fasting Experience

I don’t think I’ll ever forget the incredible experience I put myself through beginning on the evening of April 10th through Sunday, April 17, 2011 when I consciously chose to do one of the most unlikely things for the first time ever in nearly four decades of living–I embarked on a one-week fast–ON PURPOSE–just to see how I would do. This isn’t something I just flippantly decided to try on a whim, though. I had asked my readers in this February 2011 blog post if they had ever tried an extended fasting period like this before and so many of them responded with their feedback about how it went for them–good, bad and ugly. In fact, one sweet Christian lady named Wendy blogged daily about her own 40-day fast after her pastor challenged their congregation at the beginning of the year to do it for spiritual renewal. So many other people I talked to about fasting shared with me how amazing they felt both during and after fasting that I concluded this was something I wanted to try for myself.

This personal interest in doing a one-week fast actually started ruminating in my mind way back in November 2009 when I interviewed a Boston College brain cancer researcher named Dr. Thomas Seyfried (listen to him share about how doing an annual 7-10 day water fast can be used as a therapeutic means for preventing cancer starting at around 27:48 in the interview). At the time I thought the idea of going without food for a couple of days, much less a week, was virtually impossible (and crazy!) for me. I was already dealing with some reactive hypoglycemia that saw my blood sugars dropping out of the blue even eating low-carb foods. However, this seemed to normalize itself last year when I went on my “eggfest.” So with my concerns about my blood sugar causing me issues beginning a genuine attempt at a weeklong fast, the only question was when to do it. After attending the low-carb science conference in Baltimore the weekend prior to this and knowing the 4th Annual Low-Carb Cruise wasn’t coming up for a few more weeks, I decided this was the perfect time to give it a go. And so I decided to do it in earnest.

I’ll admit that I went into this extremely skeptical whether I’d be able to last very long. It’s not that I didn’t have confidence in myself that I could do it, but it just seemed too implausible for a food lover like me to lay down the fork for an entire week. My expectations for attempting this were wide open and I simply wanted to go through the experience just to see what it would be like. So many people asked if I was doing this to lose weight and the emphatic answer is not at all. Any weight loss on a complete fast would not likely stay off once food is reintroduced to the body. That’s not to say a few stubborn pounds of fat wouldn’t find a way to leave my body and that’s never a bad thing. But my primary purpose was to monitor how I felt going without any food for a week. Here’s my 7 daily update videos about how each day of my fast went:


I learned so much more than I could have ever bargained for in a variety of ways:

The first three days for me were some of the most difficult because my body was screaming at me to eat something. I felt “spacey” for much of the time as if everything around me was running in slow motion. At the same time, my thoughts were clear and I was fully functioning despite having no food. And honestly, I felt good for most of the time through this fast. Days 4 and 5 were the BEST of the seven as I experienced the big “whoosh” of renewed energy that I had heard so many people share would happen. Day 6, though, I struggled early on with a strong desire to eat again and by Day 7 when I was at church I felt absolutely horrible feeling like my blood sugar had dropped to a level that zapped me of all my energy. When I saw a reading in the 50s and could barely stand up around 2PM on the final day of the fast, I knew it was time to break it.

I didn’t measure my blood sugar every single day, but the few times I did show readings like the one you see above in the 60s. Sure, this is below the around 80 fasting blood sugars I generally see on my healthy low-carb lifestyle, but that’s what happens when you don’t eat any food at all. Controlling blood sugar and giving your pancreas a week to rest from producing insulin (if you aren’t a diabetic) is an excellent reason for attempting a fast like this. My weight on the other hand was monitored each day starting at around 261 when this began. The first few days saw about a pound a day come off and then Days 4-7 saw a couple to several pounds drop. While I wasn’t doing this to lose weight, it certainly produced a sizable drop on the scale of 13 pounds in one week. I fully expect to put some of that weight back on this week as I return to eating again.

Believe it or not, I decided to keep up with my exercise routine during my fasting week and I did a whole lot better than I thought. I knew not to push it too hard and if I told my wife Christine if I started to feel dizzy or anything that I would stop. Even still, I played competitive volleyball TWICE and did a couple of Pilates/yoga classes with no problems to be concerned with. Although I was “spacey” on the volleyball court, I was able to perform quite well running, jumping, and blocking spikes on the front row! BRING IT!

Yes, I know it’s gross to talk about, but it was a part of the fasting experience. I expected to visit the porcelain goddess frequently in the first couple of days or so, but when I was still seeing massive amounts of “stuff” coming out late in the week during the fast, that was pretty freaky. It reminded me that there’s a lot more waste in the body than we even realize and doing this fast may have helped clean a good bit of that out.

I did not stop taking my regular supplements for the duration of the fast. I continued on with my multivitamin, Vitamin D3, magnesium, probiotics and other array of vitamins that have been a part of my healthy low-carb lifestyle for years. Perhaps I could have given this routine a rest for a week, too, but I didn’t.

This was my first attempt at fasting for longer than a day ever, so I didn’t have any idea what to expect beyond what I had heard from others. One of the challenges I found was how to ward off the symptoms of not eating anything. I was guzzling a lot of water throughout (very important for anyone fasting), but I decided I wanted more. So I added in some diet sodas again to help get me through. While I realize consuming diet soft drinks is controversial to some people who think you shouldn’t ever consume this stuff, it’s what I chose to do during my fast. Right or wrong, it’s what I did and I believe it helped me get through it. To me, it was most important to make it to the end of the seven days with non-caloric liquids throughout. I also used chicken bouillon cube broth after a few days on the fast as recommended by a dozen low-carb researchers and practitioners for electrolyte balance. It most definitely helped me feel revived and renewed when my energy started to wane. While I didn’t do this fast primarily for spiritual purposes, it certainly helped remind me to focus on the vital role God plays in my life on a daily basis.

When I started sharing my fasting experience and what I was doing on my menus blog, at Facebook and Twitter, on YouTube and elsewhere, the reaction I received was probably the most surprising part of this entire process. It ran all across the spectrum from encouraging words from people who thought this was a great idea and cheered me on all the way to people telling me I was killing myself and undermining the very low-carb lifestyle principles I promote. Wanna see just a small taste of what I’m talking about? Check out my favorite quotes both positive and negative from the fasting week:

And it seems I’ve inspired another low-carb blogger named Steve Cooksey to try a one-week fast, too:

GO GET ‘EM STEVE! It’s interesting to see how quickly his fasting blood sugar numbers have fallen.

I hate to say I’d change anything about this first experience trying a one-week fast. The experience was what it was with all that I did. If I had it to do all over again (and perhaps I’ll try this again sometime), I’d go in one direction or another. Either a full-out water only fast or a coconut oil-based fast for some nourishment. I had on my protocol of things to do for this fast to add in coconut oil if the hunger became too much to bear. It never did, but I can’t help but think if the addition of coconut oil to the mix might have made a difference in the way I felt. It might have stoked some hunger, but maybe not. I guess that means I’ll need to try it again sometime and do it that way just to find out.

After the fast ended, I decided to write to the man who inspired this one-week fast–Dr. Seyfried himself–who I met in person at the Baltimore Nutrition & Metabolism Society Symposium the weekend before I started. When I told him what I had done, he said he was happy to hear I “survived” my fasting experience. Noting my concern about feeling bad on the final day of the fast, Dr. Seyfried said this “surprised” him because “most people who do the water-only fast feel good on Day 7” and that blood glucose levels in the 50s are “good and should not make you feel bad.” He said the vitamins I took and bouillon may have sent “mixed signals to the body” which made it more difficult.

Dr. Seyfried noted that a cancer-preventing fast should probably be done using distilled water only and nothing else:

A therapeutic fast should not contain any nutrients. The body will release vitamins from fat and minerals from bones during the fast.

He explained that the weight loss on a one-week fast like this is mostly water weight because the fasting process depletes glycogen stores which retain most of the water in the body. Dr. Seyfried noted that there is some “minor” protein loss “especially if fat is mobilized” and he lamented that I didn’t measure blood ketone levels with a ketone meter like Medisense Xtra. He explains this is better than measuring ketones in the urine using Ketostix as is popular among low-carb dieters.

If your blood ketone levels are elevated then you are definitely burning fat.

I’ll be sure to do that the next time I do an extended fast. When I asked what this weeklong fasting does to cancer cells, he said the “damage to mitochondrial respiration is the origin of all cancers.”

Fasting will induce cellular autophagy thus allowing the cells of the body to consume damaged or defective mitochondria. Metabolism of ketone bodies will reduce damaging oxygen radicals while enhancing the metabolic efficiency of the mitochondria. Fasting prevents cancer by enhancing the metabolic efficiency of mitochondria and by eliminating damaged mitochondria.

With the diarrhea I experienced midway through my fast, Dr. Seyfried said this is “not expected” because it’s a way the body is cleansing itself of toxins. He recommended a book Herbert M. Shelton called Fasting for Renewal of Life that gets into the nitty gritty of what is happening when you fast. I’ll be sure to read this book before beginning my next fast. He reiterated the importance of consuming only distilled water or a small amount of non-caffeinated green tea. As for the vitamins I took during my fast, he said they are “not needed for short fasts (less than 20 days).” If a 20-day fast is short, then remind me not to try a long one!

He didn’t have an issue with me exercising during my fast “as long as it is not too extreme.”

I think walking is fine, but I am not sure about Pilates, volleyball or other types of vigorous exercise. Fasting is a time for rejuvenation and relaxation. Excessive exercise will prevent this and potentially harm the body. This might have accounted for some of your tiredness.

That’s a good point. Perhaps laying off the exercise just for the week of the fast would have been a better idea that trying to keep my regular routine up. I’ll remember that for the next time I attempt to do this. All in all, it was quite the education going through my first-ever one-week fasting experiment and I feel fantastic just a few days afterwards since I reintroduced food into my diet. I’m back to engaging in daily intermittent fasting of about 19 hours a day which doesn’t sound so daunting anymore after going a week without eating! I’d love to know what you think about this idea of fasting for a week, whether you think it helps or harms in the long run, and if you have or would ever try this for yourself. Leave your comments below! I expect a wide array of ideas and opinions and all are welcome here.

  • Kelly

    Thanks for sharing.
    I know a lot of judgment comes with the sharing of something like this. Glad you stuck to your guns and did what you set out to do.

    I haven’t really read anything about fasting more than a day (I do I.F. sometimes), but not having to think about food at all for a week. . .sounds relaxing to me 😉

  • mary titus

    I know I shouldn’t let it bother me but we’ve discussed fasting so much in the past. I surprised me that you got so many negative reactions to doing this. I do not believe that you become more insulin resistant from fasting. How does one becme insulin resistant in the first place? By eating, not by fasting. My theory about fasting and insulin resistance is that fasting reduces the work on the pancreas. The pancreas does not need to shell out unneeded insulin. As we’ve also read here, cellular strength increases and the outer layer becomes more plyable, or should I say less caloused or resistant to insulin. Thanks for sharing this experience with us Jimmy.

    • I appreciate all your support last week Mary.

  • Michael

    I remember not too long ago hearing your interview with Robb Wolf where you asked him about IF and told him that you really couldn’t go more than a few hours without eating. People will have different opinions about your fast, but what seems clear is that your metabolic health must continues to improve to the point where you can do this. And I must say, the Dr makes a convincing case. I definitely want to try … some day not too soon!

    • It is amazing how adaptable you can become this. Try it buddy…it’ll change your perspective.

  • Michael Kovacs

    Jimmy, thanks for sharing your experience. I too have been doing 24 hour IF, eating just one meal a day and nothing but water the rest. I plan to do a one week fast as you did for health reasons but I need to wait till I am on holidays first, as my job is too physically demanding. I cant believe some of the negative comments from some people. Anyway Jimmy, Take care, and keep up the good work that you are doing. You are appreciated by many, many people. If you ever make it to Vancouver, Canada, let me know. I would love to sit and have a coffee with you and just shoot the breeze at English Bay.

  • Belinda

    Wow Jimmy, you have inspired me. If you can do it, maybe I can give it a go! Well done.

  • GrannyMumantoog

    Congrats on completing your task. I’m glad you seem none the worse for wear. Not sure how I feel about fasting to tell the truth. I know many people & cultures swear by fasting for long periods of time, and of course I know that the human body can go several days without food if they need to… I am curious about the 19 hour fast thing, however. I remember I read about it quite a while ago but I forget…senior moments are hell. Do you go 19 hrs everyday without eating?? I always read that several small meals every 2-3 hrs was optimal for the body & always felt bad that I couldn’t ever seem to accomplish that 🙁 So if you only eat 5 hrs a day that would mean only a couple of meals right?? I’m probably just not getting this. Maybe you could put in a link to the original article(s) you did about the 19 hr thing. Thanks, Sue
    PS: I hope this doesn’t look as nonsensical to you as it does to me.

    • HAHAHA! You’re so funny, Granny. The five-hour eating window is something I started doing periodically in my menus beginning in January. I later found out there’s actually a plan out there called “Fast-5” that actually advocates for doing just that–eating all your meals in a five-hour window and then fast for the next 19 hours. I’d love to interview the author of that plan to hear the reasoning behind it, but it matches up with the intermittent fasting teachings of people like Robb Wolf. If you’re hypoglycemic or diabetic, it’s probably not such a good idea though.

      • GrannyMumantoog

        Thanks for the link. Interesting for once in a while but don’t think I’d do it regularly either.

      • Curtis

        Hi Jimmy,

        If you would like to have Dr. Herring (of the Fast5 website) as a guest on your show, I think you can email him at info@fast-5.com. I hope he agrees to be on the show because he has a great story to tell.

        • I’d DEFINITELY love to have him on my show…I’ll e-mail him now. THANK YOU Curtis!

  • Congratulations Jimmy on your successful fast! I do IF but I’m not sure I could go for a week. I have ADD and fat is uber important for my brain function.

    Your dedication is admirable. Isn’t it amazing how those of us who have had years of weight issues can really do something difficult when we put our minds to it yet we carried those additional pounds failing diet plan after diet plan? That’s the glory of blood sugar regulation done with high nutrient foods. I believe that once the body is nourished, so many other things that were impossible in the past are made easier. Maybe we have more nutrient to draw from in storage?

    The poop part is pretty interesting too! I love to talk poop…..you know our buddy Sean and his Poop 2.0 videos!

    In good health my friend!

    • I didn’t mention this in my post, but it helped that I haven’t been addicted to sugar for many years. I couldn’t imagine doing this if I was still stuck on the cravings for sugar.

  • Mike

    Hi Jimmy,
    Good job! I believe the brown stuff in poop is liver bile and the solid stuff is gut flora. I also think you don’t need any supplements for a week. The major problem of diarrhea can be entirely blamed on the magnesium because it sucks water out of you cells into the colon. If there’s no food to mix with this water, you get the “runs”. Try distilled drinking water from the grocery store. It’s great and only costs like $1.10/gallon. I’m planning to read the recommended book – thanks.

    • I’ve got good ammo for the next time I do this. 🙂

  • Lucy

    I’m inspired! My biggest concern is I don’t have a lot of body fat to burn away. I’m one of the skinny metabolic syndrome sufferers, I’d probably look like a stick figure after a week without food.

    Thanks for sharing not only your experience, but what you’ve learned about what you did right and what you did wrong. We can all only make decisions on the best information we have at the time, and the more we know the better it gets.

    • Lucy, I don’t know that body fat has much to do with it. I’m sure this could clear up some of the metabolic stuff you’re dealing with. Lemme know if you try it!

  • Lucy

    I forgot to add that I read Sheltons’ books on food combining way back when, and the summer I practiced that was the best I ever felt in my life. A lot of people poo-poo food combining; and there is minimal “hard science” to support it – except when you break it down, a low-carb diet is in essence, properly combined.

  • Jimmy,

    If we are doing something… people will complain. If you do nothing… people will complain about it.

    Bottom Line for me???? … a diabetic friend tried a daily fast because of my postings and for the first time in YEARS she was sub 100mg/dl. The very next day …she was 79 mg/dl.

    I could CARE less about negative criticism when affecting positive changes in people’s lives.

    That ladies life has been changed because I read your post … I know you have personally changed 1,000’s of lives directly … and even more indirectly. For the WIN!!! 🙂


    • THANKS Steve! You can’t blog for as long as I have without letting some things roll off your back. I appreciate your encouragement.

  • Congratulations! Reading this actually made me think I will try it sometime in the future, which is something I’ve never considered before. It certainly won’t be anytime soon since I’m pregnant. Thanks for the insights and the “guts” to try it!

    • Tiffany, it’s certainly something to consider on a personal level for everyone who is concerned about their health. CONGRATS on the pregnancy!

  • Thanks – am hoping to say the same to you and Christine in the very near future 🙂

  • ValerieH

    This is so interesting! You might want to talk to Chet Day (chetday.com). He has done lots of water fasts. He had a health newsletter in the 1990’s (the kind that was mailed). I read his archives and many articles on his site. He used to be very interested in Natural Hygeine, which promotes water fasts for healing. Within the last year he went low carb.

    • Awesome! I’ll look him up. Thanks Valerie!

  • A few years ago I would have ran the other way screaming if someone suggested fasting… because they must have meant sprinting – surely not giving up food.

    LCing definitely helped your metabolism – and health! IF probably further prepared you for this. I remember reading in a few books that giving food a rest helps clear out the waste in your cells. (I’m probably paraphrasing more than necessary) and then I hear/read it several more times (some through your sites). I don’t think it hurts anything as long as you feel good. After all this time it seems how we feel is more important than any other marker. It’s usually the best indicator that something is right/wrong.

    Thanks for being the guinea pig! Now we have an idea of what to expect. I won’t be doing it anytime soon while little man is at home, though. I think I’d be upset cooking food and not eating it. Maybe this summer?

    • Holly, I’d love to see how you do with a total one-week fast. Lemme know if you decide to do it!

  • Galina L.

    Great job, Jimmy!
    I love your blog. Doing IF was my New Year resolution, and I managed to stick to it, however, my longest time without food was 22 hours.
    I think , your BS drops could be due to diet soda consumption. Body may react on it with small release of insulin, and it should affect the sugar level. It is not a criticism, just a thought. I would try to find something to help too, if I were you, especially during first time.

    • They were invaluable this time around. Will attempt to do without them next time.

  • cremes

    I’ve done several 8+ day water fasts. Here are a few things I have learned along the way.

    1. Do it in the summer. As your metabolism slows, you get cold. It’s easier to deal with that when it is 80 degrees outside.

    2. The first 3 days are the toughest. Once you get over that hump, your body switches to ketosis, your hunger pangs stop and you’re in the clear.

    3. You do *not* need vitamins or other supplements. Water only. Your body will release vitamins from your bones as it needs them. This is only a potential problem if you have been malnourished for *years* prior to attempting a fast.

    4. Fasting is mostly a mental challenge. I noted how “addicted” I was to the routine surrounding my thrice daily feedings. Breaking the habit of stopping for breakfast, lunch & dinner is one of the hardest things to do. At some point you realize you aren’t even hungry; you miss the routine!

    5. After about 5 days, my average sleep time goes from 8 hours to 5 hours. Fasting reduces the need for sleep.

    6. After pooping everything out the first 4 days, don’t be surprised if you have another random poop about 9 or 10 days into it. 🙂

    7. The whites of your eyes will be absolutely brilliant about a week into it. Your tongue will also get really pink and healthy looking.

    8. The first time I fasted, I noticed that 6 days in I had a weird acne breakout on my shoulders. It cleared up within 2 days. It has not happened again on subsequent fasts.

    9. Hyperventilation can occur due to ketone build up in your blood according to a doctor I spoke to. It also suggests there might be an issue with kidney function. If you start to hyperventilate while fasting, break the fast immediately. Then, go see your doctor and get your kidneys tested.

    10. Don’t do more than one 5+ day fast per year. Throughout the year I’ll do a 24-hour fast 1 or 2 times per month.

  • As I’ve come to fully embrace everything about the LC lifestyle, including getting over my fear of eating a lot more fat than previously, I’ve started to try intermittent dry fasts lasting around 36-40 hours. I did find myself somewhat woozy and spacey around the 24 hour mark, and, for some reason, when I do these fasts, I find I keep wanting to soak in a long hot bath a couple of times a day. I’m now getting myself together mentally to go for a week; your experiment has definitely given me a push. Thanks for the rec on the book; also, I’ve read that even water diverts energy to digestion that the body could otherwise use for detoxing, which is why, on my short career in fasting thus far, I’ve done dry fasts. Question: do you happen to know what the absolute minimum amount of water you can get away with daily on a 7-10 day fast? Thanks for sharing about your experience in such detail – really, really appreciate it.

    • I don’t have any idea, but I wouldn’t want to deprive my body of water during a fasting period. From what I’ve learned, water is an essential part of making it work.

  • mary titus

    Here is my theory about water. Ketosis is meant to protect the body during famine. Realistically during a real life famine, would there also be a lack of safe drinking water. So wouldn’t ketosis also sustain the body through say a drought? Therefore when ketosis reduces our need for food, wouldn’t it also reduce the need for water?

  • Hi Jimmy,

    I read your story about your week’s fasting and I would add just a few things:
    In Europe and especially in Germany fasting is very common just as a relaxation period and/or as a cure (paid by Medical Care). And many diseases are cured only by fasting!
    The advantage there is that everybody and everything supports you. The physicians do check ups before, during and afterwards, you get massages, enema’s, there’s a sauna, swimming pool, fitness room, meditation, yoga; it’s quiet, peaceful and all the people do the same as you do!
    Normally you get yourself ready before a week’s fast. You won’t eat meat, dairy, grains etc anymore, only vegetables and some fruit; normally I drink the last day before my fast only vegetable juice.
    During the fast you may walk one or two hours (In Germany they organize specifically walk fasting!)
    The enema’s are very important and also some sodium sulfate to clean the small intestines!
    After the fast you should also build it up with only cooked vegetables and some fruit.
    You really don’t need vitamins (unless there is a medical reason), maybe some magnesium and potassium.
    I used to feel much more energetic afterwards for at least 3 months! It’s a very healthy thing to do and it’s based on what we’re evolved to do! We make a metabolic switch from a sugar to a fat burner and you may keep it that way afterwards……as long as you do some form of exercise and burn the carbs you might eat.

    By the way, I read about an interesting method here in Holland called “sportvasten” (translated: something like sports fasting; http://www.sportvasten.nl , you could have the website translated by Google). It’s developed on Paleo principles by a guy named dr. Remco Verkaik, medical biologist). The goal of the program is to let people make a metabolic switch from sugar burner to fat burner. And it’s done by the combination of intense sport and fasting, that’s even the essence! It’s supported by some supplements to make the switch easier. Some impressive improvements are (after 10 days fasting – 4 days preparation, 4 days real fast, 4 days build up), combined with ONLY real intensive training of 30′ a day): 12.5% better VO2max, fat% from 11 to 8% and some other markers of fitness with a semi professional biker. Of course the people will also have to change their food intake after the program to loose some more fat and/or keep the switch. This 10-day’s program is only for people who more or less eat natural and are active in some sports. For other people there is a preliminary 4 weeks program to change the way they eat and sort some light sports program, in order to make this sport-fasting program possible at all.


    • Wow, that is so cool George. Thanks for sharing!

  • Jeanine

    The information on fasting to prevent cancer is really interesting. I’m curious, does a fat fast do anything similar to prevent cancer?