Natural immunosuppressants?

There are some health conditions that require suppressing your immune system. These include common allergies like asthma and autoimmune diseases where the body attacks it own tissues, such as rheumatoid arthritis, lupus and polymyostis.

Dr Ulugbek Nurmatov, Devereux and Sheikh reported that vitamins A, C and E could help prevent asthma in April 2012.
They were only effective against asthma, though, because the researchers found no evidence of the same effects on other allergies.

 "Conclusion: The available epidemiologic evidence is weak but nonetheless supportive with respect to vitamins A, D, and E; zinc; fruits and vegetables; and a Mediterranean diet for the prevention of asthma. Experimental studies of these exposures are now warranted." Allergy and Respiratory Research Group, The University of Edinburgh, Scotland, UK

See report.