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Introducing Fast-5

Back in 2006, my wife Judi heard from one of our nieces about Gary Long, a man walking across the country to lose weight. He was walking from St. Louis to New York City, then starting again from Los Angeles to continue back to St. Louis. Judi asked if she could walk with him starting in Los Angeles. Gary said okay, and in August of 2006 they set out from LA. Judi blogged during the walk on the Fast-5 website, but updates to this website meant leaving the blog content behind. By request, we've put her blog back on the web in its original, somewhat antiquated form. The blog doesn't permit comments, but they're welcome here. You can see the early days of telling the world about Fast-5 in her blog here: Photos are included in some posts starting on August 25.


I didn't knew about it! Thank you Bert.

This experience is very inspiring and could give some similar ideas to apply.

Hello Dr. Bert!

I'm just beginning the Fast-5. I am a 48 year old female who has just had some blood work done showing I am anemic and estrogen dominant. It's likely this is pre-menopause. Dr. is doing more tests though just to be sure.
Any specifics about going into menopause with this program?
Also, I take quite a few supplements a day. ex: Multivitamins, Vitamin D, Omega 3's, Vitamin C, Fibre, and just added some iron and some herbal hormonal supplements. I normally take most of these in the morning, but if I am fasting until 5 p.m. would you recommend waiting to take them all until the break-fast?

Thank you for this site. It is very generous of you to offer this information for free to us all. To me, that say's your intentions are truly altruistic and genuine. A rarity these days.


There are no specific differences to expect for Fast-5 during menopause. Several women have reported a reduction in symptoms during menstrual periods, so it may apply to menopause as well. However, most of the symptoms of menopause are hard to quantitate and tend to be highly variable. Since you can't just flip Fast-5 on and off like a switch, it's difficult for one person to judge whether Fast-5 is making a symptom better or worse -- you can't do both at the same time to compare exactly the same day's symptoms with one way versus the other.

I generally suggest taking vitamins, etc., for which timing doesn't matter after the window is open. They won't necessarily break your fast, but since I can't tell you precisely how much intake is too much to get the effects you want, it's just simpler to take them with or after break-fast.

Thank you for your response.

Thank you so much for the relative sanity of this diet. I have for so long been yo-yoing from insanely restrictive diets to absolute binge frenzies. The Five lets me actually balance between those two extremes. I've lost ten pounds so far. I know it probably won't keep coming off that fast (some was hormonal that I probably would have lost anyway) but I sure feel good about it. Thank you for providing this "alternative" method of self nourishment. I'm sure it's not for everyone, but I'm equally sure that it IS for me. :)

I'm glad you're finding it a good fit. I respect your courage and that of the many others who have stepped out of the dogma to try something different.

Best wishes for your success!

I'm starting tomorrow. At 5 pm can I make me a smoothie, than at 7 pm I eat my dinner than?

Yes that would work within the limits. Please see the summary page for more of the details. "Eat within 5 consecutive hours" is the only rule one needs to know, and even that one can be bent a bit. How you eat, what you eat and how much you bend the rule is up to you. If you bend the rule to the point it stops working, you can always go back to what worked before.

Since reaching my weight goal of 185 about 4 weeks ago, I have modified my Fast-5 to 5 days a week (Monday-Friday). On the weekends, I pretty much eat whenever and whatever I want (which is different than the way I ate in the past). I resume the Fast-5 on weekdays. I weighed in today at 184 and have never felt better in my life and I just turned 53 last month. My recent physical was stellar except for cholesteral numbers (which have always been moderately high). Maybe I should stop eating ice cream every day... well maybe not.

Neen doing fast-5 for 4 months and have real trouble lasting more than 14 hours. I get stocmach gurgles, cramps etc. where I get very weak and light headed. Have you had these kinds of problems and how did you resolve them. The feeling of weakness and light headedness is the hardest to deal with. Have very littel energy to want to do anything.

For me, reducing the amount of carbohydrates I ate really helped with the problem. Also, you might want to move your eating window to an earlier time and see if you can maintain that new eating window (especially if you work early in the morning and/or sleep early) or conversely, move it to a later time. It all depends on what time you go to sleep and wake up.

You have to prepare for bed, sleep, go to work, commute, etc. So that 19 hour fast should really only last 8-10 hours. You go to work, and the day just flies by. Go to the gym on your lunch break, or do something that occupies your mind such as reading or solving a puzzle. Before you know it, your shift is over, and you go home, or go out, then eat your fill for another day.

I agree with spectra blue. I do LCHF and it only took me 3 days to transition to 5pm-10pm window. I'm guessing that those who break-fast with high carb meals experience much stronger swings in blood sugar, insulin levels and mood than I do keeping my carbs to ~ 50g/day . Maybe that is why it takes up to 3 weeks to make the transition for some.

Your suggestions tell me that you have probably going throught the same thing. I love carbs. Just love them. That could be the problem. I'll weight more towards proteins and veggies. It took me at least 3 months before the headaches went away. Now I deal with the stomach cramps. The cramps feel like I have acid in there. When they pop up which is towards the end of 19 hours I also feel very light headed and weakish. Anyway, I'll do more opn the protein and unprocessed food. Thanks for the suggestions.

Thank you, thank you, thank you! :-) I was one of the ones who requested this fine journal to read again (emailed you under my name..."Bella" is just part of my email address).

Truly, this story is such an inspiration and an example of how Fast 5 is not weird or dangerous. If two people - Judi and Gary - can walk miles and miles a day on one meal, how easy for the rest of us, after an adjustment period, to do so in our own, comfortable lives.

Recently, I have been thinking of the negative things people have responded with when I tell them about fasting during the day, as if it were some dangerous fad. Really? So being obese and sick, dependent on pharmaceuticals with serious side effects, like those to lower blood pressure, blood sugar and cholesterol, just so people can eat many times during the day is better than skipping a meal now and then? Sorry. Not in my book. I'll take my freedom and a little tummy rumble any day. :-)

Bert and Judi, you are wonderful for sharing the Fast 5 concept so openly. Just today, I was trying to think of ways to help get the word out. You certainly have sought all avenues, and hopefully word of mouth and living examples will help, too. Perhaps we must hold tight to the belief in the quote you included in the front of your book, Bert, that nothing can stop an idea whose time has come.

God bless and live long, live lean, live well.


The fear and danger attributed to eating less often is very strange to me. Do people think there was some study done that said three meals a day was best? There wasn't. It was just a cultural development, probably the result of middle-class types mimicking the excess of the wealthy when the standard of living rose enough to make it possible (with a lot of help from advertising).

Not only is Fast-5 usually accompanied with a drop in blood pressure (by those who have reported -- no study has been done on this) and other changes of improved health, the satisfaction of no longer being overweight and having to fight food must be substantial in terms of reduced stress, more social and economic opportunities, and even the ability to participate in more activities without reservation. The physical health benefits come with mental health benefits, and hopefully a healthier, richer (I don't mean financially, but Fast-5 does save time and money), fuller life is within reach for those who dare to eat less often.

Fast-5 (before I even knew it by that name!) has been a very natural way of eating for me on weekends but I somehow manage to mess it up on weekdays - sitting behind a desk the whole day, not moving, colleagues asking for lunch, bringing cookies, pastries, etc. Anyhow, I am trying to overcome this pressure associated with eating at work and hopefully most days it will be fine. I have noticed, however, that during summer it is much easier to do than in winter or when it is not so warm outside. Anyhow, I was wondering if anyone can provide some light on the following issue: the fast-5 eating plan/lifestyle is supposed to induce ketosis allowing the burning of fat instead of glucose. If, however, the food eating during the 5 hour window is not strictly low carb, will this not take you out of ketosis? And if yes, for how long? I guess my question is whether it is possible to be in ketosis without eating strictly a low carb high fat diet and if yes, what is the scientific explanation for it. The LCHF community seems to think that it is only possible to be in ketosis when you consume very little carbs, moderate protein and a lot of fat.

This is one of the increasing number of concepts that you don't have to take anyone's word for -- you can test it yourself with ketone testing strips or a fingerstick ketone tester. During and shortly after the Fast-5 break-fast with carb intake, the ketosis is either stopped or turned way down. After the body is through storing the fuel that was consumed, the fat cells get busy providing fuel and the ketosis returns. It is probably highest just before break-fast.

It may be more difficult to detect ketosis in someone who is well-adapted to short-term fasting because the body has increased its ketone uptake efficiency, so in such a person ketones may only show up as a trace or may be undetectable with the strips. In someone with surplus fat who is new to fasting, the ketosis can be easily detected with the strips.

So yes, a carb-containing break-fast will take a person out of ketosis, but the cellular machinery stays around so that the fat-burning can resume shortly afterward. I can't give you a precise time since that would depend on the person, the amount of carbs consumed, how quickly they were consumed, and what the other content of the meal was.

Low-carb and Fast-5 work very well together because you can't get lower-carb than fasting, and if you eat low-carb during the window, the fat-burning doesn't get shut off by an insulin bump. Many people (including me) find a hybrid of the two ("lower carb" Fast-5) to be comfortably sustainable.

Many thanks for the quick and very informative response, Bert. I do agree that the best way to know what works for you in terms of dietary plan or anything else for that matter is to experiment with oneself. I have been reducing carbs consciously since February and in general feel quite ok on a low carb eating plan for a few weeks. After several months, however, I started to find it quite restrictive and especially the high fat part became too heavy for me. It was then I started looking for something which would have the same benefits but would allow a bit more freedom on occasion. And I found your website - talk about coincidences :-) Thanks again for all your insights and mostly for remaining open minded and non-dogmatic about this lifestyle. There is hardly anything more off-putting for me than someone explaining how what they do is the one and only and the best there is in the world!!! I am much more inclined to believe/trust someone who does not pretend to have all the answers and who is not afraid of experimenting and finding out new things as they go along.

By experimenting and observing myself I have found out that my body instinctively does not want any food before exams, for instance, or any other type of sustained effort. Some days it takes no effort at all to do all the 19 hours fast, other days I become intensely hungry after only 10 hours or so. I suppose this is just how things are - nothing is the same every day. Although I did ask for the scientific explanation of what is happening in the body re ketosis and breaking the fast I feel that we could learn so much more by just observing and listening to our bodies. The fact that science sometimes cannot explain certain things does not mean that they do not exist or that they are not valuable for us. Your website have reinforced this belief of mine which I sometimes find way too easy to overlook in the busy, busy, busy world of today.