Life has been a steep learning curve, especially for the early settlers… they didn’t exactly have an instruction manual.  Our ancestors and forefathers lacked the knowledge and advancements of this modern era, but it was their struggles that got us where we are today. Such struggles include a long list of harmful items that we once believed to be safe and, in some cases, healthy. From parasitic diet fads to toxic chemicals, these items were once commonly used, and it took years of trial and error to figure out what worked and what didn’t. So just how unsafe are these items? Let’s find out!

1. Asbestos

Once upon a time, asbestos, a mineral found naturally in rocks, was regularly used for building houses. From insulation and fireproofing to popcorn ceilings, floor tiles and gas masks for the US military, it was all the rage. In 1918, researchers began to link asbestos with certain illnesses and as time went on, more and more studies began to show just how bad this multi-use mineral was. It has been linked to mesothelioma, asbestosis, lung and gastrointestinal cancers as well as pericardial effusion. Currently, asbestos is banned in over 60 countries around the world, not including the United States. 

2. Mercury

Mercury was used for centuries before its toxicity was discovered. Although it was more commonly known to be used in glass thermometers, mercury was frequently given to young children to soothe teething and to people with syphilis. It was also used to treat headaches, influenza and parasites. It didn’t long for mercury to show its true colors. Not too long after ingestion, people suffered from symptoms ranging from drooling and eye irritation to more serious conditions like motor dysfunction and kidney failure. 

3. Tapeworms

Back in the early 1900s, dieting was a big business. Pills and potions began popping up on the market and although they were flying off shelves, word of the side effects of these remedies quickly spread. Shortly after, a disturbing fad, ingesting tapeworms, began making headlines and soon many people were playing hosts to their own parasites. Tapeworms worked wonders because, in order for you to even maintain your weight, you would have to consume large amounts of food. What people did not know at the time was that tapeworms can grow up to 30 feet long and could cause a wide array of illnesses from minor headaches to more serious problems like bowel obstruction, dementia, meningitis and epilepsy. 

4. Bloodletting

Throughout history, medicine and the treatment of disease have arguably been the hardest to get right. Bloodletting dates back to the ancient Egyptians and Greeks, but it was more commonly associated with medieval Europe. Medical practitioners would puncture a vein thereby allowing the bad or overabundance of blood to flow out. It was used to treat a variety of ailments from the plague and gout to fever and high blood pressure. Unfortunately, quite a few people died from losing too much blood and it is rumored that George Washington’s death may have been due, in part, to his bloodletting treatment for his sore throat.

5. Tobacco

Tobacco, more specifically smoking tobacco was first observed when Europeans voyaged to the New World. The practice was brought back and was quickly adopted by people of all social classes. Scientists were able to quickly form connections between smoking and cancer, but the lack of evidence to back up their claim didn’t come until the 20th century. Lawsuits quickly followed and the world saw some of the biggest legal settlements in history. Today, tobacco companies are required to state the health effects of smoking, but even with that, it remains one of the most common habits in the world.