Both stem from romantic and naturalistic idealism, that‘s Part of German culture. Modernity had severed the relationship between the people and the land and nature. Christianity and Judaism were seen as invasive religions, that eradicated the natural indigenous religion.

There‘s an antisemitic strain that rejected modern medicine as Jewish, and favored alternative methods. Homeopathy, Anthroposophic medicine, new Germanic medicine, quackery, and other alternatives were supported by the Nazis.

The Nazis regulated quacks and providers of alternative medicine as Heilpraktiker (healing practitioners), a law that‘s still around today in Germany. This legitimized them in the eyes of the public until today.

It’s all pretty convoluted and there’s no clear line. Nazism as an ideology has a lot of inherent contradictions. It’s both against modernity, for a more ancient indigenous culture, while embracing modernity, technology, media, and revolutionary change. It’s very syncretic.

Anthroposophy and other alternative medicine remains popular in Germany today, especially among the educated middle and upper class. Left-liberal hippies will often send their children to Waldorf (Rudolf Steiner) schools, which you can find in every medium sized city. I have personally listened to a Waldorf teacher talk in front a group of 40ish people how the Holocaust was the result of bad karma accumulated by the Jewish people. According to him the Jewish people were were cleansed by it and transitioned now to a higher stage of development.

The success of the German Green Party, organic farming, environmentalism, anti nuclear sentiment, alternative medicine, has a direct cultural origin in the naturalist romantic idealism from the late 19th, early 20th century. The Nazis co-opted some of it, because it fit in with their Völkisch and antisemitic ideas.

Even today, you can find neo-Nazis in Germany, who care a lot about the environment and animal welfare, also following alternative quack medicine. Anti vaccine sentiment was widespread in west Germany before COVID, and the anti-vax movement was easily co-opted by the far right afterwards.