Is it harmful to swallow sperm?
"The average male ejaculation produces about a teaspoonful of semen, which contains up to 300 million sperm cells. Sperm cells make up only about 10 per cent of semen, the remainder includes water and fructose, which is a type of sugar that helps to give the sperm the energy with which to swim. Semen also partially consists of a thin, milky alkaline fluid, which is produced by the prostate gland. This fluid helps the sperm to survive when exposed to the acidic lining of the vagina and uterus.
In general, semen is composed of proteins, fats, carbohydrates and the mineral zinc, and if it is consumed the body will digest it and absorb it just like any other foods which contain protein, carbohydrates, fats and minerals. Therefore, it isn’t harmful to swallow semen. In fact, semen is also low in calories - a typical teaspoon of sperm will contain just five calories.”
From the book, Why Is Yawning Contagious by Francesca Gould, a gift from my mother in law.