[donaldc]

Unless you started exercising, these two statements are incompatible with one another (violates the first law of thermodynamics). What's more likely is you felt "fuller" from eating healthy foods and therefore consumed less calories.

Another possibility is that the food eaten affects the metabolic rate. I've known multiple people who stopped having cold extremities when they cut back on their sugar intake.

[jaggederest]

Less than ten percent of your daily energy expenditure goes towards thermogenesis. That's not going to make enough of a different to lose 30 pounds in 90 days while taking in more calories.

You need a calorie deficit of approximately half a standard daily intake to lose a third of a pound a day.

[donaldc]

Not the full thirty pounds, but it could definitely be a contributing factor. And, if one's extremities get warmer while one's core temperature remains the same, the same amount of clothing is worn, and the ambient temperature remains the same, it's pretty much a certainty that more calories are being spent on heating the body.

[jaggederest]

You're talking about an extra 50 calories a day. It's going to be negligible against the 1100-1200 calorie deficit needed for that kind of weight loss. A half tablespoon of peanut butter.

Over the course of 90 days, you'd lose a grand total of a pound of fat or so.

[donaldc]

I think it could be more than that. Studies have found that some people have burned off an increase of hundreds of calories a day just through an increase in fidgeting.

And then there's this (http://www.medicinenet.com/script/main/art.asp?articlekey=99...)

Despite the fact that all of the subjects spent the same amount of time in exactly the same confined space, the results showed large differences in the number of calories they burned. Some subjects burned as few as 1,300 calories in 24 hours, while others burned as much as 3,600 calories, a difference of 2,300 calories in one 24-hour period!

Keep in mind that most of what these subjects were doing would not be counted as "exercise".

[jaggederest]

You were talking about thermogenesis, now you're talking about different activity levels. Not the same thing at all, really.

[donaldc]

You seem to be talking about some sort of very narrow non-motion definition of thermogenesis and I am not. I guess according to you, shivering because one is cold is not thermogenesis.

If you want to know more about what I'm talking about with drastic changes in calorie expenditure, do a google search on "non-exercise activity thermogenesis".

[iopq]

No, only calories really matter in terms of metabolic rate. Your metabolic rate increases in a surplus and decreases in a deficit.