Shift workers are being warned about the impact on their health.
Research shows irregular work hours in young adulthood can have a negative health impact later in life.
Shift workers are more likely to have fewer hours of sleep per day, lower sleep quality, and lower physical and mental functions.
They have a higher likelihood of reporting poor health and depressive symptoms at age 50.
Sleep expert Dr Alex Bartle told Mike Hosking that consistency is key, and you need to be disciplined.
He says it's challenging on the body and mind when you go backwards and forwards from a day shift to a night shift.
LISTEN ABOVE

Mike's Minute: So yes, Chris Hipkins does think you're stupid
01:59

Rod Liddle: UK Correspondent on the Russian jets intercepting UK surveillance planes over the Black Sea
05:45

Grant Baker: NZ Businessman and Entrepreneur on his decades of success and failures, new book 'No Pit Stops: The Business Of Going All In'
13:06