Teen guys with dreams of one day having kids might want to rethink their after-school snack.
A new Harvard University-led study found that eating a "Western diet" – one packed with high-fat and processed foods, such as pizza, chips, and red meat – as a teenager leads to a lower sperm count and damaged sperm-producing Sertoli cells. While a change in diet can increase sperm counts within three months, damage to Sertoli cells is permanent.
You Are What You Eat
The team presented the study, which has yet to be published in a peer-reviewed journal, at the European Society of Human Reproduction and Embryology's (ESHRE) annual meeting in Vienna on Tuesday.
For it, the researchers looked at medical data collected on nearly 3,000 men with an average age of 19 prior to their joining the Danish armed forces.
Each man completed a dietary questionnaire that classified him as having one of four types of diets: the aforementioned Western diet; a traditional vegetarian diet; a "prudent" diet of mostly chicken, fish, vegetables, and fruit; or a "Smørrebrød" diet of processed meats, whole grains, cold fish, and dairy.
The researchers found that the sperm concentration, volume, and motility of the men with the Western diet was the worst, and hormonal tests led to the discovery of their depleted Sertoli cells.
"This just shows the power of diet to the way that testicles function," Allan Pacey, an andrology professor at the University of Sheffield, who wasn't involved in the study, told The Telegraph. "The concern would be that poor diet younger in life makes a change that sticks with you."
READ MORE: Men's fertility irreversibly damaged by age of 18 thanks to Western junk food diet, study finds [The Telegraph]
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