Special properties were attributed to fasting saliva. Pliny refers to the curative properties of the local application of such saliva. "A woman's fasting spittle is generally considered highly efficacious for bloodshot eyes; it is also good for defluxions of those organs, the inflamed corners of the eyes being moistened with it every now and then." In Madagascar the first spittle in the morning is called rora mafaitra, bitter or disagreeable saliva, and has medicinal virtue in healing a sore eye or ear. Among the Irish peasants fasting spittle is considered of great efficacy for sore eyes, especially if used mixed with clay taken from a holy well. This is made into a paste and applied to the eyes, and it is said that "nothing beats the fasting spittle for blindness."

"A funny comparison is if you take the biggest ungulate herd — so that would be bison, antelope, deer and elk — in Yellow Stone National Park, per meter squared — so per unit area — the fish on one of the reefs that I look at...they actually pee more than three times more [than that herd]," he said. Fish urine even dwarfs fertilizer-heavy golf course runoff — per meter squared — in nutrient content.