Telegraph [telegraph.co.uk]:
Male fertility is being irreversibly damaged by a diet of western junk food by the time men reach 18, a study has found.
A groundbreaking investigation has established that teenagers who favour high-fat and processed foods like pizzas, chips and snacks are killing off sperm-producing cells that can never be replaced.
It showed that a diet dominated by fish, chicken, vegetables and fruit is best is for protecting those cells and ensuring healthy levels of sperm.
The solution is simple: don't eat anyone's junk.