Sperm is a clean, harmless substance which can be swallowed without any ill effects. The only exception is the contaminated semen of a man who is suffering from a veneral disease.
In other cases, the sperm of adolescents is seen as a medicine for feeble and dying people.
Many years ago in Europe sperm was a common ingredient of medicines.
"When held for some time in the mouth it produces a warmth similar to spices," John Hunter observed, and this may have suggested it possessed vital stimulant qualities.
Brongersma 1990, p. 412
And so the conviction that sperm cures is still alive. Research has shown that semen does have one of the properties of penicillin: it kills bacteria.
Brongersma 1990, p. 412
The Sambia boys not only swallow the sperm, but after sucking they also rub it on their faces and chests in the hope that by so doing it will make them shiny-nosed, glistening and handsome.
Brongersma 1990, p. 411
Among the Marind, men believed semen helped heal wounds, stimulated the libido when eaten, and improved plant growth."
Brongersma 1990, p. 411
Questioned by Hite, some men said about the taste of sperm, "I don't hesitate to swallow the semen, since it has the taste of the sea." "I don't like the bitter taste of some semen." "I enjoy the taste." "I did once get and swallow a mouthful that was more bitter than any other I had had but I swallowed it anyway." "Sometimes it is quite bitter." "It doesn't always taste the greatest, it depends on the man and whether he has good hygiene. But some cum tastes great. I highly recommend it." "As to liking it, yes and no. It depends on the person's body chemistry. There is a chemical in the fluid that makes it peppery tasting and sometimes it can be strong and sort of burns your throat. Other people have rather sweet-tasting fluid. It varies."
Brongersma 1990, p. 405