I lost weight the first time I consciously quit drinking (ultimatum from my live-in boyfriend when I was twenty). I went from about 110lbs to 93lbs. I was big into fancy cocktails, and lots of them.
The last time, though, when I quit drinking, popping pills, doing coke, and smoking pot, I gained. I my weight had fallen into double digits, and when I got out of rehab five weeks later, I was about 135lbs. I couldn't eat for the first two weeks sober, so that's a huge gain. Though I'm average height (5' 4"), that's uncomfortably heavy for me because of my muscular/skeletal issues, so I set about losing it: regular, small meals, lots of water, and no sugar. Within six months, I was a healthy and comfortable 105.
These days, my weight stays between 100-108, depending upon the season. I have mobility issues and I'm not disciplined enough to keep up with the stationary bike, so most of my exercise comes from slow-paced walking and stretching. I eat very well, but no meat and little refined sugar. Dietary choices are conscious these days. It's not exactly the drunk/druggie diet of Mt. Dew and Pringles potato chips that I used to eat.
Peace & Love,
Sugah