Health Benefits of Phytoncide Phytoncide has tremendous health benefits for humans, too. Natural antibiotic kill bacteria and viruses in hair. Effective chemical-free. Naturally remove odors from food, smoking, pets, bathroom, bad breath, not just mask them. Strengthen immune system to reduce flu incidents and bacterial infection. Activate natural killer cells that selectively attack cancer cells thus helping to fight against cancer. Increase efficiency of lymphocyte cells. Prevent and alleviate the environmentally-caused skin diseases and asthma. Phytoncide Shampoo is made using these features.