(NaturalNews) Men who drink a liter of cola or more every day have lower sperm counts than men who do not drink cola, according to a new study conducted by researchers from Copenhagen University Hospital in Denmark and published in the American Journal of Epidemiology. The effect did not appear to come from caffeine.
Researchers have previously speculated that high consumption of caffeine may produce lower sperm counts. Most studies into the connection have been conducted in specific groups, such as infertile men, rather than the general population, however, and no scientific consensus has emerged.
In the current study, researchers took sperm samples from 2,554 men aged approximately 18. All the men were undergoing physical exams to determine their fitness for military duty between the years of 2001 and 2005. They also collected beverage intake data on all participants.
The researchers found that men who never drank cola had an average sperm count of 50 million sperm per milliliter of semen. Men who drank a liter or more a day, in contrast, had only 35 million sperm per milliliter. While this difference is not drastic enough to qualify as a problem by World Health Organization standards, lower sperm counts have been well established to correlate with lower fertility.
A much smaller effect on sperm levels was seen in men who drank large amounts of tea or coffee, ruling out caffeine as a likely cause. The researchers are unsure whether the lower sperm counts were caused by the cola itself, or by other unhealthy lifestyle habits associated with soda consumption.
"It's important to note that the men who drank a lot of cola were also different in many other ways," researcher Tina Kold Jensen said.
Men who drank large amounts of cola also tended to eat more fast food and less fruits and vegetables.
"I imagine it's the lifestyle," said Fabio Pasqualotto, of the University of Caxias do Sul in Brazil, who was not involved in the study.