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Intermittent Fasting Guide

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My Story

While I started Intermittent Fasting in the fall of 2016, for several years before I had had a few entrepreneurs suggesting I try it. I didn't feel a huge need to do it because during my 40's I had steadily become more and more disciplined about what I ate. My basic approach was what I described as a 95% vegetarian diet: green smoothie for breakfast, light vegetarian lunch and regular dinner. Why 95%? I calculated that I only had meat in my mouth for about an hour during dinner which was less than 5% of my day, so 95% of the time I was vegetarian. ;) While many of my vegetarian friends had an issue with my characterization, the approach was basically working except for that stubborn belly fat that was hiding my six-pack. Actually, to be honest, more like a one-pack.
After seeing that this IF fad was not dying out, I decided to research it and I was really intrigued by two elements: a) the ketogenic state burns fat as a cleaner source of energy for the body and b) the autophagic process which renews the body's cells. Your body enters ketosis after ~12 hours, switching to burning fat as the main source of calories. Besides uncovering my one-pack, the consumption of ketones vs glucose is a less oxidative process for generating energy to the body. Autophagy is a fascinating phenomenon for which Yoshinori Ohsumi just won a Nobel Prize for in 2016. With a greek etymology meaning literally "eat self", the autophagic cycle involves the identification of weak/damaged cells, breakdown of such cells and then conversion of the recycled material into new cells.
So, losing weight wasn't really the primary reason I was interested in it, but rather burning fat and weeding out weaker cells. The good news was that once I started, I saw instantaneous results as my belly fat started burning down noticeably. Over time, other sources of motivation developed including: 1) valuing the experience of increased focus due to the increased secretion of the hunger hormone grelin (body is saying "Yo! We need calories; it's time to focus!"), 2) avoiding post-lunch food coma, 3) enjoying the challenge of fasting, 4) feeling my metabolism pick up and 5) eating a bit more recklessly (i.e., more calorie dense foods).
I started with 16 hours of fasting and an eating window from 12pm to 8pm or 1pm to 9pm. I simply delayed having my green smoothie until lunch. It was not a challenge as I am lucky to not have the hangry or hypoglycemia gene. It was so easy, in fact that pretty quickly expanded my fast window to 18 hours and eating only for six hours. Then 20 and 4. 22 and 2. Finally after watching a video about a teacher/weightlifter who only eats for 30 minutes a day, I pushed myself all the way to 23 and 1. Eating only from 7pm-8pm.
And it was awesome!!! I thought I had cracked the code. I had swapped my "k" diet of kale, quinoa and coconut water (the phonetic [k], obviously), for a "b" diet of beef, butter, bread and beer. I was 20 all over again chowing 1,800 calories over dinner and staying lean without putting on weight.
Unfortunately, I started to have these weird muscle twitches. Just a little bit here and there, primarily in the pectoral area. I didn't think too much of them until they started being pretty regular. I mentioned it to my team once and a concerned engineer said, "I normally don't comment on other people's lives, but don't you think you should get that checked out?" Well, I was heading out of town for a trip to Baltimore and I will never forget sitting on the bed in an AirBnB and having what I thought was my heart having consistent palpitations.
As soon as I returned to the Bay Area, I called Kaiser to set up an in-person appointment, but they recommended based on my symptoms that I do a call with a doctor right away. This doctor, as soon as I told him I was IF'ing for 23 hours started literally yelling at me through the phone, telling me it was very dangerous what I was doing, that there was no medical research in this area and he didn't want to see me as footnote on somebody else's research. He scheduled me for an EKG and the good news was that my heart was fine. It turns out that what I was having was muscle twitching from being low in electrolytes. A consequence of switching from [k] to [b] was that I was no longer consuming electrolyte-rich foods.
The short of it is that I switched back to regular [k] eating for about six months including a liter of coconut water every day. I tried a dozen brands of coconut water and like Zola the best. I continue to drink a full liter every day as the richest source of natural electrolytes. Haven't had any muscle twitching (or cramping) since.
After all the drama, my routine has settled out to this...
Start the day with a big glass of water (lemon optional) anchored to your teeth brushing.
For the time until I drink my green smoothie, I judiciously mete out 100 calories which is the suggested threshold for not breaking your fast. I am generally easily clear of that.
I wash down about one ounce of green smoothie shmeg out of our blender pitcher with 12 ounces of water as part of the cleaning process in the morning (about 20 calories). It satisfies my no waste philosophy and it works well as part of my ritual of making the family smoothies in the morning. BTW, we are going on eight years now and the three kids have only missed one week of school combined in those 24 years of school.
Then I have about 3-4 mouthfuls of Zola coconut water at various times during the day as needed based on my thirst or hunger (15 calories per mouthful) until I break my fast.
If I feel hungry, I often embrace it as a way of reminding myself that a billion or so people are chronically undernourished or experience food insecurity. A small way of feeling solidarity and making it easier to feel grateful for our privileged lives.
I will break my fast anywhere between 12pm and 4pm depending on how I am feeling and, of course, external factors like business/family events. I have very rarely done more than 20 hours of fasting anymore. As I age, I realize my body is just flat-out more fragile and while hormesis is helpful, extreme stress could result in some undesirable and irreversible consequences.
In addition to my green smoothie I will also have a peanut butter and jelly sandwich during the weekdays. On the weekends it really varies. I like targeting IF'ing every day and not stressing about when I need to break it. I average 5 days of strict IF per week, busting it with a business or family breakfast. I believe in this idea that we are designed to habituate ーeven to IF ー and so I find it beneficial to upset the apple cart regularly. This foundation of intermittent fasting combined with the no-sweat exceptions has really made it easy to follow.
Once the eating window is open I have some basic best practices which are to snack first with a cup of water then 20 minutes later if you are still hungry, a piece of fruit and then if you are still hungry, something more calorie dense (nuts, etc... ー and I do sneak in the occasional processed snack).
Dinner is whatever, but dessert again, I try to follow the water-dense fruit first and wait before calorie dense items. I have a huge sweet tooth, so I do need to watch myself. BTW, besides nutrition-free calories, for me, sugar is quite inflammatory.
Either when dessert is over or the window closes at 8pm or 9pm or 10pm (depends on when it opened), I will brush my teeth. It is a powerful ritual for ending your feeding period/beginning your fast.

There are a lot more nuances that I could breakdown (vacation, parties, food planning, grocery shopping, etc.) but let's leave that for another day. Hope you enjoy the other sections (research, videos, fasting tips) in this doc.

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