HOW TO KEEP YOUR CIRCADIAN CLOCKS IN SYNC

Dr Phillips advises keeping regular routines: “Be consistent in what time you go to bed and wake up and how you live life. If you have inconsistent patterns, you’re sending confusing signals about when it’s day or night and that’s going to have knock-on effects for all areas of health.” A good rule of thumb is to expose yourself to ‘bright days, dark nights’. Seek natural light (or white light rich in short wavelengths) during the day. Both Phillips and associate professor Cain have smart lights at home, which mimic the change from day to night by gradually emitting light closer to the red end of the spectrum. “Get the light right and sleep will follow,” says Cain.

Professor Sassone-Corsi advises working with your ‘chrono phenotype’ – i.e. whether you’re a morning or night person. He goes to bed at 1am, so he can eat his last meal at 8pm without ill-effect. “The key thing is not eating meals over too long a time and avoid having meals too close to sleep.” Electric light disrupts our clock, so he says to avoid checking your phone or devices before bed.

Associate professor Güler suggests people snack responsibly as they might be doing more damage to their bodies than just the extra calories they consume by indulging outside usual eating hours.

Shiftworker Lisa says sleeping either side of a shift helps her mental health. She also prepares healthy meals in advance to take on shifts and tries to get some exercise in on her days off.