I hadn't thought about it but I'm doing the same with my pillows since on iodine!
I saw my endo a few weeks ago and he suggested the same thing using telephone books under the bed feet. My complaint was some leg edema (which I then instead experimented with flax seeds). To the recyle bin pronto......out with the flax and in with the tellie books!
Also thinking of all the camping trips where I instinctively positioned the tent so there's a bit of slant under the bags.