Surveying 2,554 young Danish men at the time they were screened for military service enrollment, Tina Kold Jensen, from University Department of Growth and Reproduction at Rigshospitalet (Copenhagen, Denmark), and colleagues examined the association between caffeine intake and semen quality. While moderate caffeine and cola intake did not impact semen, cola consumption of more than 14 half-liter bottles a week, and/or caffeine intake over 800 milligrams a day, was associated with reduced sperm concentration and lower total sperm count. The team posits of: “the possibility of a threshold above which cola, and possibly caffeine, negatively affects semen quality.”