This is a good one... Lots of misdirection... And most of these predate modern science and modern medicine, which really didn't start until 1945 after World War II resulted in a surge of good medical research. Many of the old practices persisted simply due to the fact there were no effective alternatives at the time. And many of these topics are far more complicated and nuanced than a convenient meme.
Bloodletting for fever was an archaic practice, it faded in the 1800's after being used for at least 2000 years. An 1836 paper was important in disproving its effects. I can only apologize that as a hematologist my direct predecessors killed George Washington, even if the quinsy wasn't gonna get him. We still bleed people for hemochromatosis and polycythemia rubra vera by the way, so not all bloodletting is without a scientific basis.
Mercury does cure the chancre sores that are seen in syphilis, so there was an objective response seen there. By 1900 as proto-modern medicine began, we switched out for arsenicals, which actually did work, although poorly and with high toxicity. It was the best one could get until Penicillin G became available in the late 1940s.
Radium water was sold by patent medicine hucksters. It never achieved any significant legitimacy within the field of medicine. We like to think we are smarter now... But just wait until one of the peptides RFK is touting without any evidence is found to cause cancer due to pro-angiogenic effects... The FDA issues warnings about good ole Radithor, but did not have the legal authority to ban it!
Lobotomies were used for schizophrenia from the 1930s to the 1950s, and actually resulted in improvement for many patients, although the side effects were dreadful. Scientific studies were done showing they could help the severely afflicted. They were abandoned when Thorazine became the first effective pharmacologic agent.
Everyone smoked... and it took until 1950 for definitive proof of the linkage with lung cancer to be published. It is rather a black mark that doctors promoted it that way though.
Heroin... I have nothing to say... It was supposed to be a safe and effective treatment for "morphinism" except for the fact it hits the brain 10x faster than morphine and is much more addictive. For those who want to do away with the compromised FDA and let companies promote their products without a gate keeper... An early warning for you.
DDT... Was hugely important in malaria control and saved millions and millions of lives... It was banned only a decade after Rachel Carson published her research and wrote Silent Spring, which resulted in a massive rethinking of environmental toxins. DDT impregnated mosquito netting is still used in many parts of the world. And yes, governments did spray them in schools, because the kids had a much higher mortality rate from malaria and no better option, although this changed as the toxicities became apparent.
Dietary fat sourced from animals, saturated fats, and trans fats do indeed cause cardiovascular disease. This is well documented and not in question. By the same token, high meat diets, particularly grilled and processed meats, do cause higher rates of cancer. Again, this data is solid. Old school margarine with transfat is in fact worse than butter, although polyunsaturated oils are superior to butter, and these make up most modern margarines.
Ahhh... Seed oils... And beef tallow. What if told you a robust and extensive set of data showed that seed oils are quite safe and clearly and significantly better for you than beef tallow? Because this is the case. This is not one of the above situations where options were slim and research was done later to show a bad effect.
Statins have never been used for "everyone over 50." They have always only been recommended for people with specific risk features. They are one of the best studied agents in the medical armamentarium and quite safe. I do think the benefits are are a bit oversold personally, but for those with risk factors, they have saved many lives. The current hate on statins is like vaccines, completely unwarranted and political in nature.
P.S. In regards to Vulcan philosophies... There are numerous studies from COVID showing masks (particularly N95 masks) can protect an individual from contracting COVID and serve as a point control to prevent the spread of COVID. They aren't perfect, but on a population level, we'd probably have been better off to ixnay all the other measures taken and just have everyone wear the best mask they could get... Although, several studies showed that school closures were the strongest method for reducing COVID spread if you want to break out the political fireworks.
P.P.S. And yes... the COVID vaccines were pitiful in terms of preventing the spread of many strains of the virus (although they actually did a great job on the original strain, which is why they were initially touted this way) but the data show robust and durable protection from death and severely morbid outcomes including hospitalization. Estimates suggest 17 million hospital admissions were averted! So keep the prize in mind... Not dying. Not dying is extremely good for one's health. It turns out, respiratory viruses are particularly hard to prevent with vaccines, as we see with the flu.
P.P.P.S. This was some real fun guys! I did have to research some of these topics, happy to provide links and will post some good summaries on Statins and Seed Oils since these topics are trending right now.