There's only one correct time to eat dinner.

What time do you eat dinner? Is it 6pm so you can eat with your kids? Or maybe it's 9pm after a long day of work? Maybe it's somewhere in between. 

Well, according to new research, there is actually an optimal time to be eating dinner - and it's very specific. 

The research suggests that eating dinner after 6pm, or significantly late, can have a negative impact on our body and the way it processes fuel to keep us healthy.

Watch: What I Eat When with Silvia Colloca. Post continues below.

A survey by Youfoodz found that 11 million Aussies are sitting down for their final meal each night between 7pm and 10pm. 

They also found that 71 per cent of us don't tend to eat at the same time each day. It's our work schedules that are the main culprit for this.

Why is eating dinner after 6pm not ideal?

A good question! 

The answer comes down to circadian rhythms, our body's internal clock. 

Circadian rhythms are basically physical, mental, and behavioural changes that follow a 24-hour cycle, like an internal clock that is built upon natural processes. It controls our hormones and metabolism, as well as many other bodily functions. At night, our internal clock tells the body it's time to relax, and so our metabolic rate slows down. This means digesting the food we consume can take longer. 

A study published in the Science Journal in 2022 found mice who ate in a 12-hour window that aligned with the start of their most active time of day, improved their health and increased lifespan.

No, we aren't mice. But it was food for thought for scientists. 

A study involving thousands of humans then found that weight and health outcomes are better among those who eat earlier during the day, rather than later at night.

Dr Gina Cleo is the Director of The Habit Change Institute and author of The Habit Revolution. Speaking with Mamamia's news podcast The Quicky, she explained exactly what eating dinner after 6pm does to the body. 

"Essentially our bodies take time to digest our food. It takes energy for the digestive system to separate all that food and absorb it. And when we do that, it can actually be really hard to sleep. It can interrupt sleep. That's the main difference between eating in the day and eating later on in the evening," she said.

Listen to this topic be discussed on The Quicky. Post continues after audio.

What's causing society to be eating dinner later?

There are a myriad of factors, the majority of which are lifestyle-related, explained Dr Cleo.

History does tell us that centuries ago, people would eat dinner far sooner in the day than between the now-popular 7pm to 10pm. But that's the nature of history - the times have changed, and so have our priorities and circadian rhythms.

"From an evolutionary perspective, I don't think there's something biologically different going on - it's our lifestyle that is causing us to eat later on during the day," Dr Cleo told The Quicky. 

"Ideally dinner should be had three hours or more before you go to bed. So for most of us, that means eating dinner or our last main meal at 6pm."

What you can do if you're someone who eats dinner later.

Here lies the problem - 6pm just ain't going to cut it for a lot of us. Life is busy. It takes a while to make dinner. A lot of people don't get home until at least 6pm after a long, tiresome day at work. And then there are shift workers to consider. 

Of course, the point of the research isn't to make those who don't have dinner at 6pm feel sh*t about themselves. Rather, the scientists behind it have said it's about being aware and simply keeping it in mind.

If you do have the capacity to switch your 8pm dinner to two hours earlier, give it a go. Otherwise, Dr Cleo recommends people who eat dinner late can have a bigger lunch versus a bigger dinner to help with digestion and sleep. She also says meal prepping is a great way to save on time and bring that dinnertime closer to 6pm.

Ultimately, Dr Cleo wants you to know this - it's okay to just do you. 

"Some of us are morning people and some of us are night owls. I'm a huge fan of listening to your body, being mindful so who cares what everyone else is saying."

What time do you like to have dinner? Feel free to share with us in the comments below!

Feature Image: Getty.

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