Not just placebo. Homeopathic products have nanoparticles that affect cells.

There was recently a major victory for homeopathic supporters in North America.  A class action lawsuit had been brought against two U.S. homeopathic pharmaceutical manufacturers for allegedly making false and misleading representations about the effectiveness of the ingredients.  However it took the jury less than a day to find that the defendants did not breach any express warranty or violate the California Consumer Legal Remedies Act.

The expert who spoke in defence of the Homeopathic manufacturers spoke about how nanoparticles have an effect in biological cells....

"Dr. Iris Bell, a former Harvard psychiatry instructor and holder of a doctorate degree from Stanford University in neuro- and  biobehavioral sciences who has consulted with Highlands, Inc. to design clinical trials.  Bell testified about her scientific studies in multiple chemical sensitivity and homeopathy, including how "nanoparticles" and "nanobubbles” can have an effect in biological cells. Dr. Bell opined, “It is very clear that nanoparticles in low doses are capable of capable of creating hermetic effects…similar to vaccine.” Dr. Bell explained how “hormesis” is a medical principle that describes how small doses of a substance can trigger the opposite effect of high doses of the same substance."

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