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A January Experiment: Intermittent Fasting

A friend and coworker told me about intermittent fasting a few years ago. She was doing it as part of a weight loss competition at work… She was one of those folks that says they want to lose weight, but - I’m not really sure why they actually need to? My wife does that too - doesn’t need to lose weight but makes plans to do-so anyway.

Anyway - this woman was doing intermittent fasting by not eating for most of the day. At the time I thought I’d never do that… I’d just get “hangry” and be mean to folks around me. I didn’t want to do that…

I’ve fasted before. Fasting was part of the initiation into a Boy Scout program I’d done. We weren’t supposed to eat for a 24 hour period - only drink water. That was difficult - I spent a lot of time thinking about food, feeling hungry, and thinking about how stupid it was. I had service work to do all day, and that occasionally distracted me for large chunks of time. At the end of the day they hosted a “cracker barrel” for us, a ton of small foods and deserts that we could feast on.

When that fast was over I realized it really wasn’t that big a deal to miss food for a large chunk of time. Realizing, in retrospect, exactly how easy or difficult a thing is, is really a benefit of lots of training programs.

Military training often works the same… “Run across this log! Then jump down and flip yourself over this board!” I’m Air Force - I’m probably never going to need to run across a log or help my team all flip over a board, but now I know exactly how easy those things actually are. Both are much easier than I would have expected previously.

I’ve effectively been forced to fast during military trainings, too. There have been long periods where food is just not available, or you’re too busy to take time to eat. Getting through that was much easier when I remembered just how easy it was from Boy Scout days.

My wife’ll tell you I’m not always the most pleasant person to be around when I’m hungry though. I don’t enjoy being that guy.


I read about intermittent fasting for the second time in the book Antifragile. The concept of antifragility is pretty natural to me - it’s similar to necessary features in many engineering control systems that show up electrically or in computer algorithms. Antifragility is also a natural consequence of evolution and natural selection, and if you’re building computer algorithms to simulate those two you become intimately familiar with it. I’ve built such algorithms to play games like tic-tac-toe and Connect Four. You stress the game “participants”, eliminate the parts that are the worst at playing the game, and recombine the parts that are good. Eventually this automated process of stress, assessment, selection, etc. produces participants that are much better than when they started.

The author, Nassim Taleb, mentions that he does intermittent fasting. He describes it as a method to become more antifragile, personally. This reason for fasting really resonated with me.

He also mentioned that our ancestors routinely didn’t have food for a day or two - their guts emptied out periodically. Perhaps there’s some natural body functions that can execute during that time that we don’t get to exercise normally. My daily routine is normally to keep something reasonably small in my belly - beans for breakfast, apple and orange spaced out as snacks during the day, small/medium healthy lunch (that doesn’t make me fall asleep), and whatever for dinner with a beer. The potential health benefits seemed very unproven to me when reading the book - but also very unlikely to cause harm to someone otherwise healthy, free, and worth an experiment.

Lastly - I’ve read a couple articles recently describing actual scientific results finding that intermittent fasting is healthy for you. It seems like the early days on this research, but initial results aren’t bad. This article from Harvard Health talks realistically about the results so far. Some specific folks doing specific types of intermittent fasting had improved blood sugar, blood pressure, and lower appetite. Other studies found improved gut health, cholesterol, etc. - in rats. Good enough for me to try! Down-side - folks with very low blood sugar might get dizzy, lose their balance, fall over and break a hip. It’s not recommended for older folks.


The first week of 2020 I decided I’d do intermittent fasting through the end of January. I wanted to:

  • Learn to deal with being hungry without getting hangry
  • Practice being uncomfortable so I can look back on this time and feel better, when I’m uncomfortable later
  • Give my guts a break like our ancestor’s got
  • Reduce my daily intake of calories
  • Lose a little weight

Those last two were my least concerns, but the holidays, a vacation, and a small running injury had me about 10 lbs higher than I try to stay. All that eating and drinking had slowly increased the amount of food I naturally felt like I wanted. I knew I didn’t need to snack so often, or eat meals as large as I did, but I find that when I’m eating more then I want to keep eating more.

There are two most-popular ways of doing intermittent fasting - 16/8 and 5/2.

16/8 fasting involves not eating for 16 hours every day, then eating normally for 8 hours. 5/2 involves eating only 500 or 600 calories for two non-concurrent days each week (500 for women, 600 for men - 1/4 of daily calories).

My job is fairly low stress right now, and I do like eating normally at least some of the time - I decided to do 5/2 fasting on Mondays and Wednesdays, switching days if something during the week makes it sensible.

The first week I didn’t need to go into work. I could get hangry at home or at a coffee shop and just avoid people that I might affect with my hanger. After that I’d have to just figure it out…


Each day I’d make two hard boiled eggs in the morning and wait as long as possible before eating them with Tabasco and salt - 140 calories. I’d limit lunch to 150 calories (low-sugar instant oatmeal packets are a good fit for this…). Then for dinner I’d still have 300 calories or so, and try to wait until 1900 before eating it. I let myself drink as much black coffee and tea as I wanted.

The first week was tough. I actually started at the end of December, so Wednesday 1 Jan 2020 was my second fast day. I thought about my hunger a lot. Working on projects distracted me, but the time when I was just hanging out with my wife gave me space to think about hunger.

The second week was much easier. I still thought about my hunger a lot, but found it easier to spend hours not thinking about it.

The last couple weeks I would make my eggs in the morning and it would be 1300 or 1400 before I really needed to eat them. That let me skip lunch calories, and I’d have 460 left for dinner. I found that our leftover turkey, the smoked salmon, and tins of sardines were relatively filling for the easy-to-meter calories. I’d eat a bunch of spinach and tomato with low-cal salad dressing… A baked potato with a little butter and a bunch of 0% greek yogurt was a tasty, easy, quick, low-cal and filling dinner option.

At times I considered keeping the experiment going past January. I felt pretty great about what I was doing, and like it wasn’t that hard. I was making life simpler by not needing to think much about food and eating, and I was saving a bunch of money.

The last week in January though - I was tired of fasting. I was tired of not having a beer with dinner a couple days a week, not having a glass of whiskey while watching TV with the wife. I was missing the diversity of food I’d normally eat on those two days - I wasn’t bored, just missing some of the joy I get from eating. And I really enjoy tasting food. On my last fast day I got invited out to lunch at a pizza place… It’s annoying to sit and watch folks eat pizza, even if your belly is already full. It’s more annoying when you’ve only had two hard boiled eggs all day.



  • I got much better at ignoring my hunger, and I don’t think I had any incidence of unchecked hanger. I tried to be careful about it, and I think I succeeded.
  • I was unconfortable much of the time, but once I ignored it for a little while I usually forgot about it. I’ll be able to look back on that and handle it more effectively in the future.
  • My guts got a break twice each week, and their general performance changed for the better around that period. They’re normally pretty great guts, but even better after fasting.
  • I naturally ate less on most non-fasting days… Immediately after fasting I wanted to eat all the things - on fasting days I’d think, “I’m gonna eat tacos tomorrow!” Or burgers. The day after fasting - sometimes I’d follow through on that, and usually I’d start with a bigger fancier breakfast than usual… But generally after catching up a bit I just wasn’t starving. I just accidentally ate lunch really late and a small dinner a couple of those days. Then on other days I’d smooth out and find myself wanting less junk.
  • I lost about 10 lbs and am back at about 190 - right around where I like to stay.

The experiment was entirely successful. The negatives I found were entirely predictable.


  • Less desire to work out hard - it’s tough to feel motivated to run while being hungry, it’s tougher to feel motivated to run faster, pushup, situp, pullup, and squat, which is what I got into in December
  • Less joy from eating and drinking - this is less joy overall for me…

I’m not going to keep this up in February. I don’t feel a need to. I think I do want to periodically do this again - I’ve considered “every January”, or once a week… But I think one day a month is what I’m going to start with. First Monday of every month after February.