The best bedding materials for a good night’s sleep

The best bedding materials for a good night’s sleep

It’s winter, so many of us will be getting out or buying winter bedding.
But how much of a difference does bedding make to your thermal comfort? Maybe a certain textile ?
Is it wool or other natural fibers like cotton? How about polyester? With so much choice, it’s easy to get confused.

Here’s what we found when we analyzed the evidence—not just for winter, but for the summer ahead.

The importance of bedding

We rely on our bedding for maintenance to help us sleep. And the right textiles can help regulate our body temperature and wick away moisture from sweat, promoting better sleep.

In the colder months, we’re mainly concerned with the insulating properties of a textile – keeping the body warm in and the cold out. As the temperature rises, we’re less concerned with insulation and more concerned with wicking moisture away from sweat.

Another factor to consider is the breathability of a fabric – how well it allows air to pass through it. A breathable fabric helps keep you cool by allowing body heat to escape.

It also helps keep you comfortable by preventing moisture build-up. By releasing excess heat and moisture, a breathable fabric makes it feel cooler and more comfortable against the skin.

Different textiles have different properties

Some textiles are better than others when it comes to insulation, moisture wicking or breathability.
For example, cotton and wool have small air pockets that act as insulation to provide warmth in cold weather. Thicker fabrics with more air pockets tend to be warmer, softer and more breathable. But these factors are also affected by fiber type, fabric weave and manufacturing process.
Cotton and wool are also breathable fabrics, which means they help regulate temperature.

While cotton absorbs the moisture (trand) from the skin, it does not remove it effectively. This retained moisture can make cotton feel sticky and uncomfortable, which can lead to chills in hot weather.

A woman asleep in bed.

We rely on our bedding to help us maintain a comfortable sleeping temperature. Source: Getty / Kiwi/Getty Images/iStockphoto

But wool is very absorbent and effectively removes moisture. In warmer weather, when we sweat, wool fibers allow airflow and moisture transfer, promoting efficient evaporation and cooling of sweat and preventing overheating. So wool (in different thicknesses) can be a good option both in summer and in winter.

Linen, although breathable and has moisture wicking properties, offers less insulation than wool and cotton due to its hollow fibers. This makes the underwear less effective at keeping you warm in the winter, but effective at keeping you cool in the summer.

Polyester is a synthetic fiber that can be made to trap air for insulation, but is not naturally breathable. It usually absorbs moisture poorly. So it can trap sweat next to the skin, causing discomfort. However, polyester can be specially treated to help control moisture from perspiration.

What sheets help you sleep?

As part of our review, we were unable to find any studies that directly compared sheets made from different textiles (eg plain cotton and flannels) and their impact on cold sleep.

However, linen sheets are particularly effective in warmer conditions. In one study, conducted at 29C and high humidity, linen sheets promoted less wakefulness and fewer stages of light sleep than cotton sheets.

How about doonas?

If you don’t heat your bedroom at night in winter, a goose down doona (one made of fine goose feathers) might be an option.
These promoted the longest, deepest sleep, followed by duck down, then cotton when sleeping at 11°C. This may be because down provides better insulation (by trapping more air) than cotton. Down also has a lower thermal conductivity than cotton, which means it retains heat better.

Choosing between a wool or polyester doona? In a wool industry-funded study that two of us (Chow and Halaki) co-authored, there wasn’t much of a difference. The study in young adults found no significant difference in sleep at 17C or 22C.

So how do I choose?

The choice of bedding is very individual. What is comfortable for one person is not the same for another. This is due to variations in body size and metabolic rate, local climate, bedroom temperature and building insulation. They can also affect sleep.
This variability and wide range of study designs also makes it difficult to compare different studies on the impact of different textiles on sleep. So you may need to experiment with different textiles to find what works for you.
By Associate Professor Chin Moi Chow, Cynthia (Zinzhu) Li and Professor Mark Halaki
Chin Moi Chow is Associate Professor of Sleep and Wellbeing at the University of Sydney.
Cynthia (Zinzhu) Li is a PhD student studying menopause and sleep at the University of Sydney.

Mark Halaki is Professor of Human Movement at the University of Sydney.