One, thongs compress the anal capillaries and make people 6 times more likely to suffer from hemorrhoids than normal people.
Two, thongs compress the pubic area and make women three times more likely to suffer from gynecological diseases.
Three, the anus has E. coli and many other bacteria that are bad for your health, and thongs can spread these bacteria.
Four, there are parasites such as pinworms in the anus, and wearing thongs will spread the parasite eggs to other places.