Bedroom Humidity – What’s The Best Level for Sleep?

4 Min Read | By Ellen Conning

Last Modified 1 December 2023   First Added 23 November 2023

This article was written and reviewed in line with our editorial policy.

Whether it’s the gentle drizzle of spring or the heavy downpours of autumn, one constant remains – humidity. In fact, we tend to experience a mean average of 75% humidity, even at the peak of summer. Last winter, however, hit an average of 87% humidity. Unfortunately, such high levels can disrupt your sleep, turning your bedroom sanctuary into an environment that’s not great for sleep.

Don’t worry, though – we’ll go through how to recognise any issues with bedroom humidity, how it impacts your sleep, and the ideal conditions for the sweetest of dreams.

How does humidity impact sleep?

Picture this: your body, nestled under the covers, begins its nightly voyage through sleep cycles. The initial stages, with REM in full sway, gradually give way to the deep, slow-wave sleep, a period of rejuvenation where your body mends itself.

Now, imagine high humidity barging in like an unwelcome guest, disrupting this delicate dance. It not only heightens wakefulness but also shortchanges the precious slow-wave and REM sleep, crucial for bodily repair and memory consolidation. In essence, too much humidity in the bedroom becomes the nocturnal nemesis of your overall health.

What's the best humidity level for sleep?

Studies have varying details when it comes to the ideal humidity level, but thanks to the waves of work done, we can give a general range to aim for – a sweet spot between 40% to 60%. In certain studies, people have found that REM and stage 3 sleeping patterns were significantly decreased at 75% humidity compared to the same temperature (35 degrees Celsius) at 50%.

Meanwhile, going too low, into the dryer side of humidity, can also have an impact. It can lead to dehydration, irritated nasal passages, and other symptoms. This, according to a different study, is due to more particles in the air, though there are other factors at play.

A green cup of tea steaming in a bedroom, on a wooden bedside table. In the background, messy white sheets and grey curtains can be seen.

How can I tell if my bedroom is too humid or dry?

Signs of a humid environment:

It can seem obvious to recognise when a room is too humid. The almost thick feeling on the skin and damp feeling in the air are telltale signs of high humidity. But they’re not the only ones. It’s also worth looking out for:

Signs of a dry environment:

On the other side of the coin, an environment that isn’t humid enough can also lead to some key issues. According to a study on dry indoor air, some of the signs you may spot in such a space include:

  • Dry skin
  • Sore throat
  • Nosebleeds
  • Increased static electricity
  • Eye irritation

Tips for handling humidity for sleep

Now we know the best humidity for sleep, as well as the best ways to handle dry and over-humid conditions, how do we ensure our bedrooms are primed to help us sleep? Here’s a quick list of tips for both wet and dry rooms:

For decreasing humidity

  • Open windows – Allow moisture to escape by opening windows, especially when outdoor humidity is low.
  • Dehumidifiers – Use a dehumidifier to reduce indoor humidity; it removes moisture from the air and releases drier air back into the room.
  • Choose bedding wisely – Opt for breathable fabrics like cotton and rayon to stay cooler in humid conditions. Consider a cooling mattress for those who tend to sleep hot. Swap synthetic bedding for materials that absorb or wick moisture.

For increasing humidity

  • Invest in a humidifier – Easy to buy online or on the high street, these devices add cool humidity to a room, and often let you add extra snooze-assisting touches, such as essential oils for sleep.
  • Embrace houseplants for the bedroom – These can naturally increase the humidity of a room and help with air purification at the same time.
  • Try turning down the heat – A harder sell in the cold winters, but indoor heating evaporates natural moisture in the air. Consider lowering your thermostat as even a degree or two can make the difference

If you find yourself feeling muggy or too dry in the night, then making changes to the humidity of your bedroom could be the trick to getting a better night’s sleep. It can take time to get the balance right – we all sleep differently, after all – but it’s one journey well worth exploring for the sake of better rest.

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