When Gerber baby foods began to sell in parts of Africa, they continued to use their usual packaging, with the cute baby on the front. They didn't realize until later that where they were selling it, it was a common practice to help illiterate people buy things by putting pictures on the wrapper of what was inside.
I checked that one out on Snopes and, while the 1958 Reader's Digest example makes it seem as though it could be possible, it is taken as a myth. So, the rest of the "facts" might be a bit suspect as well.
I have found it helpful to do the stretching exercises my physical therapist recommends. Do some core strengthening exercises, such as the ones highlighted at The Mayo Clinic. By keeping your core strong, your back won't put itself in a position to cause that sciatica pain you are having.