Can you change being a morning or night person?

3 min read

You decide to become a morning person and start getting up early, and three days later you're back where you started. It's tempting to think, "I'm a night person, so there's nothing I can do."

How much of being a morning or night person (your chronotype) is inborn, and how much can change? Looking at the research, there are both parts that are fixed and parts that can move.

Genes play a role, but the difference is small

A study of the genes of about 700,000 people found 351 genetic regions linked to being a morning person [1]. Genes clearly play a role.

But even comparing people with the most "morning" gene variants to those with the fewest, the difference in when they actually fell asleep was about 25 minutes on average [1]. Genes create a tendency, but they don't set your daily schedule on their own.

It changes with age too

A study of the sleep timing of 25,000 people found that children are morning types, gradually become later types as they grow, reach their latest around age 20, and then drift back toward mornings [2].

Many people feel that they were night owls as students, but started waking earlier naturally with age. That may be this change.

Light moves your body clock

The other big factor is light. In an American experiment, eight people living ordinary lives went camping for a week with no electric light, only natural light [3].

The time when the hormone that prepares the body for sleep at night (melatonin) started to rise moved earlier, and their body clocks lined up with sunrise and sunset. What's more, those who had been night types shifted the most, narrowing the gap with the morning types.

In everyday life, we get little light during the day and lots at night. That may be why so many people's body clocks run late.

What you can do to shift earlier

• Get morning light: open the curtains when you wake up, and make time to go outside
• Reduce light at night: keep bright lights and phone screens low before bed
• Keep a steady wake time: don't shift it much on days off either. Shrink the social jet lag I wrote about in the article on catch-up sleep
• Cut afternoon caffeine: as I wrote in the coffee article, caffeine in the evening can shorten night sleep

You don't have to force yourself into mornings

Since genes and age play a role, not everyone can get up at the same time. What matters isn't becoming a morning person as such, but narrowing the gap between your body clock and your daily schedule.

For a night person, waking up at the same time every day and getting enough sleep is surely gentler on the body than forcing yourself up at 5 a.m. and spending a sleepy day.