Association Between Dietary Polyphenol Intake and Semen Quality: Insights from the FERTINUTS Study.

Plain-language summary

This study looked at whether dietary polyphenols (plant antioxidants found in fruits, vegetables, tea, and olive oil) are linked to semen quality in young men. It analyzed 3-day diet records and semen samples from 106 healthy men aged 18 to 35, sorting polyphenols into classes and matching them to sperm shape. Higher intake, especially of flavonoids (found in berries, apples, onions, and tea) and lignans (found in flaxseed, whole grains, and seeds), was tied to fewer defects in the sperm head but more in the tail. The head carries the DNA and the tools to penetrate the egg, so head defects hurt the ability to fertilize, while the tail is the motor, so tail defects hurt movement. No link was found to sperm movement or vitality overall.

Key findings

• Higher total polyphenol intake was linked to fewer sperm head abnormalities but more tail defects.
• Flavonoids and lignans showed similar patterns: better head shape but worse tail structure.
• Stilbenes were tied to more combined sperm abnormalities.
• No links found between polyphenols and sperm motility or vitality.