one's metabolic rate to drop.

Swore off diet drinks (new Doc, sweet gal, thought she was swearing me off soda completely) mostly because my liver enzymes were elevated, and I started believing the folks who warned me that aspartame shut down their great aunt's liver.
Diet soda was the only soda I drank, and I drank a lot of it. No, as in, a LOT. Now, at the time I DID cut most soda out, but I switched TO the leaded stuff, AND over the past 5 months, that amount has grown considerably. Not quite to the amount of diet I WAS drinking, but still.

No other real change. I STILL haven't managed to start the exercise plan she thought she was swearing me onto, and haven't made much change to my diet at all (at very least, not enough to counterbalance the amount of calories I'd STARTED drinking).

Down 40lbs.

How else am I supposed to explain that? The numbers just don't add up otherwise, because what I cut out didn't include calories at all, what I substituted DOES, and I'm removing calories from my body at a much greater rate than I was before while not doing anything different. That says what I DID cut out was doing something to my body to keep me from burning calories as well as it does now.