History

• Black walnut hulls were used by the ancient Greeks and Romans to treat stomach complaints, according to the American Cancer Society. The United States Department of Agriculture adds that the Comanche people used a paste made from the hulls and leaves to treat ringworm infections.
  
  

Benefits

• The active ingredient in black walnut hull is a pigment called juglone. Juglone may have some benefits in cancer treatment. A 2005 study by Paulsen and Ljungman indicated that juglone killed cancer cells in human fibroblasts.
  
  

Warning

• The American Cancer Society advises people with nut allergies to avoid using this product. In addition, the website indicates that as of 2010, there was no conclusive proof that black walnut could fight cancer. The site strongly discourages the use of black walnut hull in place of conventional treatment methods.