If you’ve ever felt guilty for only sleeping six and a half hours, or confused about why your partner thrives on nine, a new study out of Flinders University might put your mind at ease.

Published last month in the Australian Journal of Sleep Medicine, the research tracked over 4,000 adults across three years, measuring not just sleep duration but sleep architecture — the amount of time spent in each stage of sleep. The findings? The magic eight-hour number we’ve all been chasing might be far less universal than we’ve been told.

What the Study Actually Found

The Flinders team, led by Professor Sarah Drummond, found that sleep needs varied significantly across the cohort. Some participants functioned optimally on as little as six hours, while others genuinely needed closer to nine. The critical factor wasn’t duration alone — it was the proportion of deep sleep and REM sleep within each cycle.

Participants who spent a higher percentage of their sleep in deep, restorative stages reported better mood, sharper cognitive function, and lower inflammation markers, regardless of total hours slept. In other words, a solid six hours of quality sleep outperformed a restless eight hours almost every time.

This isn’t entirely new territory. Sleep researchers have been questioning the one-size-fits-all approach for years. But this study is one of the largest longitudinal projects of its kind in the Southern Hemisphere, and it adds serious weight to the argument that sleep quality trumps sleep quantity.

Why This Matters in Australia

We’re not great sleepers as a nation. The Sleep Health Foundation estimates that around 40% of Australian adults experience inadequate sleep on a regular basis. A lot of that is driven by anxiety about sleep itself — lying in bed watching the clock, doing the mental maths on how many hours you’ll get if you fall asleep right now.

This research could shift the conversation from “get your eight hours” to “get your best sleep,” which is a far more useful and less stressful framework.

Dr Moira Chen, a Brisbane-based sleep physician who wasn’t involved in the study, told me she’s already seeing the impact in her clinic. “Patients come in fixated on a number,” she said. “When I tell them their sleep tracker data actually shows healthy architecture in fewer hours, you can see the relief. The anxiety about sleep is often worse than the sleep itself.”

What You Can Actually Do With This

So if the rigid eight-hour target isn’t gospel, what should you focus on instead? Based on the Flinders research and current sleep science, here’s what seems to matter most:

Consistency beats duration. Going to bed and waking up at roughly the same time — even on weekends — was strongly associated with better sleep quality in the study. Your circadian rhythm is a creature of habit.

Temperature matters more than you think. The study noted that participants in cooler sleeping environments (around 18-19 degrees) spent more time in deep sleep stages. If you’re in Brisbane like me, that means the aircon is not a luxury — it’s a wellness tool.

Late-night screens are still a problem. The blue light debate has been going back and forth, but this study found that screen use within 45 minutes of sleep onset was consistently associated with reduced REM sleep. Night mode helps, but putting the phone down helps more.

Stop clock-watching. If you wake at 3am, checking the time triggers a stress response that makes falling back asleep harder. The researchers recommended turning clocks away from the bed entirely.

The Bigger Picture

I think the most valuable thing about this research is the permission it gives people to stop stressing about hitting a specific number. Sleep anxiety is real, and it creates a miserable feedback loop — you worry about not sleeping enough, which makes it harder to sleep, which makes you worry more.

If you consistently wake up feeling rested and can function well through your day, you might just be someone who needs less than eight hours. That’s not a flaw. That’s your biology.

Of course, if you’re dragging yourself through every afternoon, relying on caffeine to stay upright, and feeling foggy most mornings, that’s worth investigating — ideally with a GP or sleep specialist rather than Dr Google.

The Flinders study is a reminder that wellness isn’t about rigid rules. It’s about paying attention to what your body actually needs, not what a headline tells you it should need.

Sleep well tonight. However many hours that turns out to be.

Jess Morley is a Brisbane-based wellness writer and yoga instructor. She writes about evidence-based wellbeing at SoulShine.