Originally Posted by WhyFi

With all this talk about food, it seems like there's no better time to mention that I haven't had any... going on four days now.

After dabbling in intermittent fasting and reading about extended fasting, I decided to give it a whirl, so it's been a total of 0 calories taken in over the last oh, 84 hours or so. I've been taking supplements to keep my electrolytes in check, but other than that, the daily intake has been a cup of coffee, a cup of tea, an occasional zero calorie electrolyte drink and water. Oh, and I've also been peeing on sticks, to monitor my ketone levels.

There have been some ups and downs. My first morning, I think that I went too easy on the bike ride and didn't burn through available stores, so it was a mostly normal day with no dip in to ketosis.

I decided to ramp it up the next morning with a harder ~one hour ride and, by the afternoon, I was feeling somewhat fatigued but my ketone levels finally elevated.

Day three, yesterday, was the worst - mild fatigue, like I'd ridden a century in the morning, food and planning future meals occupied a lot of my thoughts, and I had a slight mental fogginess. Taking my family to a favorite pizza place/Italian market for lunch was a big time test of my will. Breaking my fast was an internal debate - I wasn't exactly having fun but, at the same time, I expected those lows and didn't want to quit before bouncing back to feeling somewhat normal, which was expected based upon what I'd read.

Today, I woke up feeling pretty damn normal - spirits were good, mental clarity was good and, while not feeling like a world-beater, I felt physically good. Went for a spirited ride, though I couldn't quite push as long or as hard as normal. The hunger pangs, that typically occur around meal times, were mild and brief this morning. Food has not been a siren song.

I think that I'll keep the fast at least through the day, but I may go in to the weekend, if it continues to be as easy as it has been so far today.

Oh, I've also been monitoring my weight and body composition. No loss in lean mass but fat mass and total mass is down. As of this morning, I'm the weight of an average American woman (I came in a hair under 170lbs).