BBC Radio 4's 'More or Less' series is known for checking any statistical claims that hit the headlines or go viral on social media.
They recently investigated US health secretary Robert F Kennedy Jr's statement that: 'Today the average teenager in this country has 50 percent of the sperm count, 50 percent of the testosterone as a 65-year-old man'.
To do this, they invited Professor Allan Pacey, an andrologist at the University of Manchester and former trustee of PET (Progress Educational Trust) to examine the figures and studies and make sense of the numbers.
Listen to the conversation on BBC Sounds.