Recently I've found that a small meal at midnight makes me warm enough to kick off the blankets and I run very cold. I've also found that eating dried peas with horseradish, which is sold in stores under a weird name.... if I nibble on those, my overall temperature rises quite a bit. I hope this helps.

A note for others:
I run low on thyroid, however and I've found it is due to chronic infection that I have learned to diagnose and treat myself as doctors have been very unhelpful - I have spinabifida with an open hole or fistula, so as the infection progresses, I lose my sense of smell, taste, eyesight, ...and finally enlarged thyroid

but... when I treat it, first thing I get back is my smell, then thyroid decreases in size and everything normalizes and I have energy and am warmer. I hope this helps others who wonder why their own thyroid may be fluctuating in size,...it could be an underlying infection... streptococci...or even parasites in the colon, as worms cause the thyroid to shut down, so as to create a less acidic environment in the colon.