On fasting

I’ve been fasting in a few different forms (intermittent, water-only, no-calorie) now, and wanted to write up my experiences and thoughts so far.

First, I tried intermittent fasting – fasting for 16 hours per day, eating for 8. For me, this meant eating from 11am-7pm. I did this for about 6 months. Of course, there are more extreme and less extreme versions of this – the one-meal-a-day (OMAD) folks are the most extreme.

Many people find that they lose weight when intermittent fasting, just because they’re not eating as much as they would have – caloric restriction. I did lose a little bit of weight, but that wasn’t the biggest impact for me. Instead, I found the mental changes most valuable – I was allowed to eat whatever I wanted, in whatever quantity, just only during those 8 hours per day. That took away a lot of the guilt associated with junk food, and allowed me to listen to my body instead. If my body was feeling terrible, I knew I should ease up on the junk food, or add more veggies to the next few meals.

I stopped doing intermittent fasting mostly – I try not to eat after 20:00 at this point, for a really mild form of it, but I’m not attempting to keep a rigid 16/8 schedule. I found the schedule difficult to maintain when work or special events got in the way (late afternoon teaching made it hard to eat at appropriate times!).

Last summer, I decided I would try water-only fasting for a longer period of time. I ended up doing several 3.5 day fasts, with only water and the occasional fizzy (non-calorie) vitamin-C or magnesium tablet.

Doing this taught me a lot about myself – about self-control, about my ‘need’ for normal meals and mealtimes, about how hunger is largely a mental aspect. When fasting, I became more aware of the things around me and my relationship with food. After about 24 hours, my sense of smell goes crazy, and everything that might be food smells really good. Walking past a restaurant is wonderful.

I did find that I would get headaches if I didn’t consume any salt during the fasts, so I added a pinch or two of table salt to my water each day, which removed the headaches. I was doing a fast in October, and needed to stop after about 24 hours, as I got a serious migraine that wouldn’t go away.

From a weight-loss perspective, I saw a drop of about 10 pounds (4.5kg) over the 3.5 days. Most of that was regained after the fast ended, but I did see an overall drop of about 1 pound/day of fasting.

This spring, I decided to try an easier form of the water-only fast – no-calorie fasting. I’ve done several 3 day fasts, with no food, but coffee and tea allowed. I think part of the headache issues was also related to caffeine withdrawal, as the headaches haven’t been an issue at this point.

For 3 days compared to 3.5 days, there haven’t been many differences in weight loss; slightly less due to the shorter amount of time.

This past week, I’ve completed a 7 day no-calorie fast. First, the weight loss numbers: I dropped about 15 pounds (7 kg) while fasting; I’m still waiting to see if the 1 pound/day loss is accurate after I’m eating again.

The difference in mental state between this and the 3 day fast was huge. With the 3 day fasts, I found myself very hungry and low-energy near the end of the second day and into the third day. This lead to lots of laying around, lots of watching food videos on YouTube, etc. When I was reading about longer fasts on r/fasting on Reddit, they noted that this hunger phase usually ended by day 4 of the fast, and it was lower-energy but otherwise fairly normal after that. I definitely found this to be true.

Day 4-7 of my fast was lower-energy than normal, but the serious food cravings subsided, and it was much easier than days 2-3.

In conclusion, fasting has been a great experience for me. It’s given me better insight into my relationship with food, has developed my ability to deal with hunger, and has helped me lose a bit of weight – I’m down about 25 pounds from the beginning of last summer in total, without other diet changes. I’d encourage you to try it – especially a 3+ day no-calorie fast, which I found most impactful, mentally and physically.