There were studies done about it that I have been trying to track down. I remember reading them before, but for some reason can't seem to find it anymore. The study was written about in the book, The Secret Life Of Plants, by Peter Tompkins and Christopher Bird.
The book documents controversial experiments that reveal unusual phenomena regarding plants such as plant sentience, discovered through experimentation
I can attest to the experiential truth of this. I am FAR healthier than anyone I know.