Tapeworms for Weight Loss: A Victorian Diet FadA historical health trend that involved ingesting parasites.

From the show

Historically Bad Advice

Some Victorian-era dieters believed intentionally swallowing a tapeworm egg was an effective weight-loss strategy. The parasite would live in their intestines, consuming a portion of their food and supposedly preventing weight gain. This popular advice completely ignored the dangerous, and now well-understood, health risks of parasitic infections.