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Ask the Experts


Negative air ion therapy for depression is rarely known in Japan, and Japanese critics of pseudoscience usually regard negative air ion(minus ion) as pseudoscience. Is negative air ion therapy pseudoscience?

Answered by: Michael Terman

The Japanese themselves have performed some of the most significant medical research on negative air ionization, showing that pulmonary (lung) absorption produced significant reduction in blood lactate levels in seriously stressed neurosurgical patients in intensive care (Iwama H et al., Critical Care Medicine 2002;30:1246-1249). The active ion is superoxide (oxygen with an added electron). In the United States, several centers have demonstrated superior antidepressant action of high- vs. low-density negative air ionization in double-blinded clinical trials, including publication in the Archives of General Psychiatry and the American Journal of Psychiatry. An enhanced blood-oxygenation hypothesis is currently under investigation.