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