Cotton nightwear or bamboo
Short answer: Cotton nightwear is familiar and affordable but turns clammy if you sweat. Bamboo viscose moves moisture away and therefore feels drier all night. The difference shows most if you sleep warm, and less if you tend to feel cold.
At night
The body releases moisture all night, even when you do not feel that you are sweating. A fabric that moves moisture away from the skin means you wake up with a clammy top less often. Cotton absorbs the moisture but holds on to it, so the fabric turns heavy and cool as you turn over.
Weight
Cotton nightwear of the same thickness often feels heavier than bamboo viscose. That comes from the fibre and from the way the fabric drapes. A lighter fabric follows the body when you turn instead of twisting around you. See the styles in bamboo nightwear for women if you want to feel the difference.
For warm sleepers
The difference is clearest if you sleep warm or wake up feeling too hot. Fabric, cut and duvet all play a part. A loose cut lets air move, while a close fit holds more heat. There are more practical tips in nightwear for warm sleepers.
For men
The same principles apply to men's nightwear. A set with shorts or long trousers in bamboo viscose feels lighter than cotton of the same thickness and turns clammy less often. Choose the length by how warm you sleep and how cool the bedroom is. See the matching sets in bamboo nightwear for men.
Bedding
Nightwear and bedding work together. If you sleep in a fabric that moves moisture but lie under a duvet and cover that trap it, you lose part of the benefit. It therefore makes sense to look at both at the same time. See the options in bamboo bedding.
Washing
Nightwear is washed often, and bamboo viscose stays at 40 degrees. That is enough for nightwear washed regularly. Skip fabric softener, which makes the fabric less absorbent, and dry on a rack rather than in a hot tumble dryer. All the practical rules are in the washing guide.
Fit and cut
Nightwear should sit loose enough for you to turn without getting tangled. Too tight feels warm, and too big lets the fabric bunch up. Bamboo viscose drapes softly and gives a little, so most people can keep their usual size. Choose the length by season.
See also
If you are considering a nightdress instead of a set, there is a separate comparison of the two materials in that shape. It looks at moisture, drape and washing and shows the difference clearly. Read more in nightdress in bamboo compared with cotton.
How many sets
Two to three sets let you wash without running short. If you sleep warm and change every night, add one more. It can also help to have a thin set for summer and a longer one for winter. See the whole range in nightwear.
When cotton is fine
Cotton nightwear is not bad. If you sleep cool and rarely sweat at night, you may not notice much difference. Cotton is also a good choice if you want to wash at high temperatures. The choice depends more on how you sleep than on which material is better in itself.
Frequently asked questions
What is coolest to sleep in?
Bamboo viscose, because moisture moves away from the skin instead of staying there. A loose cut and light bedding also help if you often wake up feeling too warm.
Is cotton nightwear bad?
No, but it turns clammy if you sweat at night. If you sleep cool, the difference is smaller, and cotton also handles higher wash temperatures than bamboo viscose.
Does bedding matter too?
Yes. Nightwear and bedding work together, so a fabric that moves moisture works best under a cover that does not trap heat. It is worth looking at both at once.
