In the 1920s, a German toothpaste brand called Doramad was marketed as radioactive to give users a 'radiant' smile.

Doramad Radioactive Toothpaste was produced by the Auergesellschaft company in Berlin during the 1920s and 1940s. The product contained thorium-228 and thorium-232, which are radioactive isotopes that emit alpha particles. Marketing materials from the era claimed that radiation would strengthen the 'defensive forces' of the teeth and gums while providing a biological massage through cellular stimulation.During this period, radioactivity was a popular health craze known as 'Radithor' therapy. Many consumers believed that small doses of radiation acted as a metabolic stimulant. This belief was supported by the pseudo-scientific theory of radiation hormesis, which suggests that low levels of ionizing radiation are beneficial to living organisms. Consequently, radioactive elements were viewed as premium ingredients in luxury cosmetics and health products.The Auergesellschaft company was actually a leader in rare-earth metal processing and gas mantle production, which left them with large quantities of thorium as a byproduct. Repurposing this waste into toothpaste was a clever, albeit dangerous, marketing strategy. It was not until the mid-20th century, following high-profile deaths like that of socialite Eben Byers, that the public and scientific community fully recognized the lethal risks of internal radiation exposure.The toothpaste remained on the market through World War II, and its production only ceased as the health risks became undeniable and international regulations tightened. Today, surviving tubes of Doramad are considered highly collectible historical artifacts, though they still emit measurable levels of radiation. This era serves as a stark reminder of how marketing can outpace scientific understanding of consumer safety.