Phase one of my diet plan is complete after only two days.
I wanted to start this diet by fasting: No solid food or any liquids with calories. I could tell some story about cleansing my system of impurities or allowing my digestive system to rest, but that's not really it. I don't believe either of those things are necessary. It's more of a psychological thing.
First of all, I didn't want to go straight from big holiday food fests to small diet meals. That would be depressing and the small meals would suffer greatly by comparison. Instead, I wanted to have a short intervening period without any food to make me appreciate what little food I'm going to allow myself during the next phase of my diet.
Second, I read an interesting comment on overweight eating habits a long time ago, and I think it applies to me. Most people decide to eat when they start to feel hungry. Overweight people like me, on the other hand, decide to stop eating when we're full. As soon as we get that not-full feeling, it feels like time to eat again. This makes a lot of sense to me, so I wanted to remind myself of what an empty stomach felt like.
In addition, I discovered that when I don't eat food, I don't get that after-meal food coma. I was awake and alert both days.
My original plan had been to fast for three days. However, when I got home Tuesday evening after two days of fasting, I decided out of curiousity to weigh myself.
If I plug my weight, height, sex, and age into one of the basal metabolic rate calculators on the web, I get a value of about 3000 calories per day, which means I burned 6000 calories during a two-day fast with no replacement. By the usual calculation of 3500 calories per pound, I should have lost 1.7 pounds.
Instead, I lost 9 pounds. How is that possible?
For one thing, my digestive system emptied out over two days. That's probably a couple of pounds. As for the rest, based on my understanding of what I've been reading about health and nutrition, here's what I think happend:
I had only just stopped eating, so a lot of my energy during the last two days must have come not from fat, but from the short-term supply of glycogen stored in the liver and muscles. Glycogen is a carbohydrate and stores 4 calories of energy per gram, so 6000 calories is 1500 grams of glycogen. Each gram of glycogen is bound up with about 3.5 grams of water which is eliminated from the body when the glycogen is used up. Doing the math, if I burned pure glycogen, I'd lose almost almost 15 pounds.
In reality, I didn't actually burn pure glycogen (for one thing, I don't think the human body has 6000 calories worth of glycogen) but some combination of glycogen and fat. Burning a 55/45 mix of glycogen and fat uses up all 9 pounds. If 2 pounds were food in my digestive system, a 40/60 mix uses up 7 pounds.
(Actually, I probably didn't really burn 6000 calories. The usual BMR estimation formulas were never normed against obese people and don't take body composition into account. Calories burned by physical activity are burned by muscles, not fat, and most of my body weight is fat. If I only burned, say, 4000 calories, then I must have burned about a 70/30 mix of fat and glycogen.)
Anyway, I was now hungry, I was looking forward to any morsel of food I could get, and nine pounds was an awful lot to lose in two days. So I declared victory and nuked up a dinner of Stouffer's stuffed peppers (360 calories).
It was delicious.
