Funny you should ask. That was my thought the first time I saw it. I actually passed over it due to the idea it might be cold. We Fibromites don't do cold well, and some of us in menopause, don't do heat well, so what do we do well? Anywho, I digress.
I got desperate one day, very stiff sore neck, arm, shoulder and I would have bought an igloo if I thought it would help. The spout where you add water is on the underside of pillow, so fibrefill surrounds it. Therefore, although you can adjust the firmness by varying the amount of water you add, because the water sack is underneath, it is not cold. Were it cold, I would just put a heating pad on low, underneath and that would be that. I haven't had to do that.
Did you read my bit about the 3 ft. really plush, low heat heating pad you lie on. Man is that great. How to solve the delemna, Fibro needs warm, meno needs cold. I lie on my heating pad, on low, bed buddy wrapped around sore shoulder/arm, and leave the window open a bit to breathe cold air. Wow, no wonder I have such close calls getting to B.R. at night, I am like two boa constrictors trying to eat one another. What a sight, cords dangling off me going in all directions. The dogs run under the bed when they see me coming.lol