Wool vs Cotton, what’s the difference?

Wool vs Cotton –  one is from an animal and the other is from a plant, they’re both natural and breathable, but which one will help your child (and you) sleep blissfully?  Not all natural fibres are created equal, there’s actually a bit of science to it and why either wool or Cotton are better for sleep.

Where Cotton is a versatile fabric, it’s absorbent, easy to care for and is far more breathable than many manmade fabrics; its fibres lack the complexity of wool. Merino wool is soft, light, warm and comfortable, and its complex fibre makeup brings its temperature regulating benefits to life.

Which is best to keep your child comfortable throughout the year?

The fact that you’re reading this blog post means you’re likely making an educated decision on the type of children’s sleepwear you’d like to buy, particularly sleepwear that will put an end to the cold night wake ups. It isn’t easy to know how to safely and comfortably dress children for bed throughout the year, particularly here in Australia. Let’s break down Cotton vs wool into which is better based on the actual properties of each natural fibre.

Keeping your child warm or cool

Is wool breathable? Merino wool is a front-runner for keeping children warm (and cool) thanks to the unique crimping in its fibres. If you’ve ever looked at raw wool closely, you will notice the crimp in the fibres. This crimping plays a big part in temperature regulation by allowing the wool fibres to trap warm air and release as needed to cool down.

Merino wool is a great choice of sleepwear for children who experience night sweats. In fact, a study of 6,381 children found that 12 per cent experienced night sweats every week, it’s a common problem.

Toddlers have a higher ratio of sweat gland density to adults, meaning the density of sweat a toddler produces is higher than an adult. A toddler’s sweat glands can be triggered by numerous things, including overheating, fever and night terrors.

When a child sweats in woollen sleepwear, they won’t get cold; they stay dry. The wool fibres absorb the moisture to produce heat. This unique phenomenon is thanks to tiny pores in the cuticle cells of the wool fibre that allow water vapour to pass through the wool fibre. Wool can absorb up to 30% of its weight in water without feeling wet. Pretty impressive!

Unfortunately, though, cotton fibres let warm air escape very quickly and are only good insulators when dry. If your child sweats while they’re asleep, the moisture will remain against their skin with no means of escape because the Cotton fibres collapse when they become wet. When the fibres are wet, they let warm air escape. It’s the moisture that draws the heat away from the child’s body and leaves them to feel cold.  Although Cotton is breathable, lightweight and good at keeping a child cool, it lacks the power of wool for keeping a child dry and warm.

Want to keep your child warm? Remember – moisture is the enemy of warmth – if your child’s skin is wet, it’s more difficult for them to remain or become warm.

If your child has a temperature above 38°C, please see a doctor. 

Cotton vs Wool: Which is better for sleep?

To support the comparison, a study undertaken by the University of Sydney, Australia and funded by the Australian Wool Innovation, sheds some scientific light on which fibre is best for better sleep.

The study found that participants experienced a better night’s sleep when they slept in or under wool.  In both cold (17 degrees Celsius) and neutral (22 degrees Celsius) conditions, participants who used a combination of wool sleepwear and bedding had a better sleep compared to when they used non-wool sleepwear and bedding.

In hot (29 degrees Celsius) conditions, wearing wool sleepwear saw participants sleep significantly longer; reflecting faster sleep onset and waking up less frequently.

In babies, hospital research points the same way. In research summarised by the International Wool Textile Organisation, researchers found that weight gain in underweight newborn babies in hospital was 61% higher when they slept on a wool underlay rather than cotton, and babies sleeping on Merino settled more quickly, cried less, fed better and gained weight faster.

That was supervised hospital research, not advice for home. At home, babies under 12 months should sleep on their back on a firm, flat mattress, with the cot kept free of loose bedding, pillows, toys, lambswool and underlays. Merino is best used in what your baby wears, such as a Merino sleepsuit.

With sleep playing an important role in the brain development and growth of babies, no wonder Merino has been the reliable choice for parents during these early years.

Wool vs Cotton, we are so lucky to have access to these natural fibres in Australia. But, if you want your child to remain comfortable, fall asleep quickly, and to stay asleep longer, dressing them in Merino pyjamas and layers makes complete sense.