The April 29 Health & Science article “Looking for alternative treatments? Look here,” on alternative medical therapies, included a seriously misleading comparison between homeopathy and vaccines. Specifically, it stated, “Homeopathy functions in much the same way as a vaccine.” This is false.

Vaccines contain measurable amounts of antigen molecules, which stimulate the immune system to produce antibodies to specific diseases. The mechanism is well understood and consistent with the accepted laws of chemistry and biology.

By contrast, homeopathy is a pseudoscience, based on nebulous notions developed long before modern scientific research. Homeopaths maintain that the more dilute a substance is, the more potent it is as a remedy. Not surprisingly, controlled studies have not shown that homeopathic drugs are more effective than a placebo.

The Post does a disservice to its readers by suggesting that homeopathy works pursuant to the same principles as vaccines.

Ronald A. Lindsay, Alexandria

The writer is president of the Center for Inquiry and the Committee for Skeptical Inquiry.