A normal male ejaculation (about one teaspoon’s worth) contains between five and 25 calories and a minimal amount of protein. Semen is only one percent sperm; the rest is composed of over 200 separate proteins, as well as vitamins and minerals including vitamin C, calcium, chlorine, citric acid, fructose, lactic acid, magnesium, nitrogen, phosphorus, potassium, sodium, vitamin B12, and zinc