Hymowitz says that American men have struggled with their adult identity since the mid-19th century.

FORBES: As Women Advance, Are Young Men Stuck?

Their study of more than 7, 000 people suggests exposure to bleach and other chemicals is a factor in one in six cases of adult-onset asthma among British people in their mid-50s .

BBC: Cleaning products 'linked to adult asthma'

He was seven when he started a course in 2012 for the Basic Assessment, which is the first adult basic beekeeping exam where the average age for those taking part was mid-40s.

BBC: Hebden Bridge youngster's buzz from beekeeping