By the time I was 10 yrs old I knew salt water helped my eczema, by the time I was 15 and driving I spent every weekend at the beach, which is only about 20 miles from me. My mom always accused me of becoming a useless beach rat... Even just the salt air helps which I discovered in my fifties when we had our boat and spent almost every weekend on it. By then I did not play in the water much but I did sit on the waterThe salt bar is one of my favorites. My recipes tend towards 80% salt. I use it to wash my face in the morning - my skin is easily and often damaged and prone to breakouts - salt bars seems to help heal damage more quickly, make breakouts go away faster, and prevent breakouts - all of which kind of makes sense. E.g. when I lived in California, every time I came back from the beach my skin was amazing for the next week; after you get a tattoo, the tattoo artist advises to wash it in saline/salt water until it heals up; salt water is used to clean/irrigate wounds in hospitals, etc.
A not-so-fun to read but interesting literature review that basically says salt water is good for treating psoriasis and beneficial to skin in general, but it depends on the ratio of salt:water:
"Salt water and skin interactions: new lines of evidence" (Carbajo and Maraver, 2018) PMID: 29675710 DOI: 10.1007/s00484-018-1545-z
Sugar solutions have also been used in the past for washing, cleaning and irrigating bed sores or pressure sores.
I also make a sugar bar just like salt bars. Yes, it does work and no sting!!
If salt bars are made with 100% salt and poured in a loaf start checking around the 45 minute mark. They can usually be cut within an hour. Gloves should be worn but I admit I do not do as I say, which my hands never appreciate...