John Henry Tilden (January 21, 1851 – September 1, 1940) was an American physician and natural hygiene proponent best known in circles of alternative healthcare for his criticism of pharmaceutics and for his theory explaining disease via "toxaemia" which influenced the field of naturopathy.

At age 17, the younger Tilden joined the medical office of J. Fellows, of Nokomis, Illinois, and studied medicine another two years.

[7] Historian Victoria Sheldon has noted that "By linking vital force with naturalistic concepts of inner blood, cells and the looming danger of outer pollutants, Tilden forwarded the American naturopathic stance that modernity was often harmful and causative of disease.

Tilden's views about toxaemia influenced Harvey and Marilyn Diamond's book Fit For Life.

Hall of Science-Based Medicine wrote that Tilden's concept of toxaemia had no experimental evidence and was based on errors, distortions and speculation.

She concluded that "It was not entirely unreasonable for him to think that way in 1926, but his ideas have been completely superseded by 8 decades of advances in microbiology, genetics, histology, immunology, physiology, and other disciplines.