Mushrooms (rishi) have polysaccharides that boost the immune
system, fight tumors and lower blood pressure. Reishi also
contains the ling zhi-8 protein, which boosts the immune
system, too. Supplementing with reishi is considered to
be very safe, but patients undergoing organ transplants
or using immunosuppressive drugs should be careful because
any immune-modulating substance can interact adversely.